Can anyone explain the transformation information within a Lego Digital Designer LXF file? I've been taking a look at the structure of the LDD files recently to see if it's feasible to create a plugin for 3D studio max that allows you to directly open LXF files for higher quality rendering...

It seems possible, but to get some preliminary tests happening I just need to understand exactly how the transformation string works:

transformation="0,0,1,0,1,0,-1,0,0,0.40000009536743164,0,-0.40000009536743164"

It seems pretty obvious from playing around that the last 3 relate to the position of the piece, and the first 9 somehow relate it's rotation (and perhaps 1 or 2 other things I'm not aware of yet). If anyone knows I'd love a detailed explanation as it would save me a LOT of messing around =)

Also are there any good resources of info on lxf files? I have only come across fairly basic stuff so far, would love to find a good resource...

There's a fairly in-depth discussion on the Eurobricks Digital Designer Forum in the post Understanding LDDs LFXML Schema, where the transformation element is defined as:

  Transformation contains 12 comma separated double precision floating point values that represent the first three columns of a 3d transformation matrix and are thus able to handle any linear transformation. It's something that you'll need to learn for yourself but the first 9 entries handle rotation, the last 3 are translation. It's worth noting that the origin of most bricks is at the bottom with the y-axis heading up through the center of a stud, this makes rotations around the axis of the stud slightly easier. Brick width is 0.8, brick height is 0.96 and plate height 0.32. This probably ties in with real world dimensions in some form, but I don't have the details to hand. The double precision floating point format can't necessary cope with precise decimal values as we might expect to see them, therefore you'll see slight deviations from the values given above, eg. -0.79999935626983643 instead of -0.8. Those 0.707 values are 45 degree rotations, they correspond to the sin or cosine of 45 degrees (or PI/4 in radians) and are part of the transformation. Transformations are in world coordinates.

As Philo points out in the comments, the values that The_Cook queries as "probably ties in with real world dimensions" are indeed the sizes of bricks in centimetres, which means you should be able to transform between systems nicely.

In response to your final goal (building a plugin for 3ds Max) what you're really going to need is a complete set of high-quality meshes - the LDD format works with part models rather than vertices/faces/edges/etc. that 3ds uses. Therefore what you'll probably want to take a look at is a tool to convert from LDD to something like LDraw (you could just use the "Export" function in the LDD file menu), and then use the LDraw model library as your basis for importing into 3ds, or use the features in LDView to export to .3ds (the older, text based file type 3d Studio used before it became "Max").


Is it possible to build a full-size house with Lego bricks? I want to build something big.

Should* I build a complete house (interior and everything) with lego bricks?

* By "should" I mean, will it be safe? How big can I go? How much do you think it will cost?

James May built a full-sized LEGO house for his TV show James May's Toy Stories on the BBC back in 2009 using around 3,500,000 bricks. Whether you'd actually want to do this yourself...

During the episode they spent some time with engineering students working out the most load bearing configurations of bricks especially for the upper floor, as well as working on the general structure.

To get around the insurance requirements, in the end they resorted to building the house around a wooden frame including floors - and although they did continue working on the beams, and James did stand (rather nervously) on the final designs, they don't appear to have been released.

With regards to the rest of the house (i.e. fixtures and fittings) there were some issues as I recall:

Comfort - obviously lying or sitting on LEGO bricks without any covering is uncomfortable.
Water Proofing - at one point in the show James shares a LEGO "glass" of wine with Oz Clarke - only to have most of the wine leak out of the glass. Without some sort of sealant, or multiple offset layers the gaps between the bricks aren't water-tight.
Clutch Power - LEGO bricks are held together by friction (Technic pins not withstanding), and tend to break apart under incorrectly placed loads quite easily. This may be an issue when it comes to chairs, doors, etc.

Wikipedia article
Show on YouTube (part 1/5)


Fix for monorail sticking at monoswitch? I recently acquired an old monorail set, and I'm having problems getting it to work properly. It works fine on normal track, and it is able to continue on or stop at a monoswitch when the switch is set accordingly.

However, it isn't always able to reverse directions (it often just stops) at a monoswitch, and once stopped, the switch usually isn't able to get it started again. It seems like the switch on the side of the motor isn't quite getting pushed all the way in. It runs fine again once I push the switch all the way in.

The behavior is somewhat dependent on direction. Although it isn't able to start from a stop at a monoswitch in either direction, it is more often able to reverse direction going one way than the other.

I'm wondering if anyone has experienced this behavior, and if there is a way to fix it.

If it makes any difference, the motor is from 6990 from 1987.

Maybe the plastic is worn off just enough that the switch is not pushing the pins completely anymore.

Debug step 1:
When the train pins are in the switch zone there shouldn't be a lot of space between the point of the pins and the face of the switch. If it looks too loose that could be the problem.  A way to test this would be to put some clear scotch tape on the faces of the switch.  The faces are highlighted in red in this picture:

If the problem persist you could add more layer(s) and test again.  After four layers if this doesn't fix the problem I would try something else.

  Results: The switch works with four layers of tape. The new question is "Between the motor pins and the switch, which one is worn out? One or both?"

Debug step 2:  Testing the switch with a second motor would be helpful. Do you have a second motor?  In any case let's inspect the motor pins and the switch faces.

The two motor pins are (I assume) made of plastic.  The end point of each pin should not not be worn down. One way to check that is to compare the two.  If one is rounder then the other that gives us important information.

The switch faces (highlighted in red in the previous picture) should be a perfectly flat surface.  Is there a slight groove at the height where the motor pins hit the switch? Again. this would be important information.

  Results: The switch faces are not worn but it looks like the motor pins are rounded off.

Debug step 3:  Testing & fixing the motor pins.

Before trying to fix the motor pins I would suggest one last test.  With no tape on the switch, you could add tape layers to the motor pins and try to reproduce the successful test of step 1.  This should work without problems.

As for fixing the motor pins.  I would suggest to use one epoxy glue drop at the tip of each pin. After the epoxy is cured you could test and if necessary sand off any excess thickness.

  Results: Epoxy on the motor pins fixed the problem.


Using two color sensors simultaneously I am new to the world of robotics, and I'm preparing a new project with my students. Our goal is to make a self driving robot that can read colored signs from the road in order to turn right or left a specific angle. For example, if the color sensor 1 detects red color, and at the same time the color sensor 2 detects blue color, the robot must turn 90 degrees right. What's the best programming approach to do this? Consider that the total number of combinations could be up to 49 since each color sensor can read 7 colors.

There will certainly be some mechanical and robotics questions that you'll need to figure out, such as where on the car to position the sensors, and how to ensure that the car is reliably reading both colors at every intersection. (Which brings up contextual questions like "are there discrete intersections?")

From a programming perspective, 49 possible options is kindof a middle ground.

You could have a systematic representation. For example, each color could map to a digit, and so the pair represents a two digit base-7 number of 2π/49 radians (where 0 means go back the way you came). I don't actually suggest that particular scheme, but something like that could work quite well.

You could just have a lookup table. Or a lookup table of lookup tables. In a C-like language that would look something like

table = [
  'red':  ['red': -90, 'blue': -45],
  'blue': ['red': +90, 'blue': +45]
];
turn_degree = table[first_color][second_color];

I would call that the "normal" approach, although you're getting toward the upper size of the table one might really want.

You could also treat one color as a modifier for the first:

first_table = ['red': -90, 'blue': +90];
second_table = ['red': -45, 'blue': +45];
turn_degree = first_table[first_color] + second_table[second_color];

This is secretly the same as that first option I gave (base7), but more flexible, easier to read, and easier to explain to kids. And you could use multiplication instead of addition if you wanted.

A robotics consideration: Will the car always correctly sense which color is the "first" color?

If not, then there's actually only 28 (21?) possible combinations. You can still use any of the above methods, but additionally you'll define an ordering of the colors (so for example, you'll just decide that green is "less than" blue). Then your "first" color will always be the lesser of the two colors, regardless of which sensor sensed what.

But seriously, how should you do this in a classroom?

If either sensor sees red, the car will turn left.
If either sensor sees blue, the car will turn right.
If either sensor sees yellow, the car will turn 15°.
If either sensor sees green, the car will turn 45°.
If either sensor sees orange, the car will turn 60°.
If either sensor sees purple, the car will turn 90°.
If either sensor sees black, the car will turn 135°.
If the car doesn't see two colors, or if the colors don't clearly say what to do, then the car just keeps going forward.

first = get_sensor_one();
second = get_sensor_two();
directions = ['red': -1, 'blue': 1];
degrees = ['yellow': 15, 'green': 45, 'orange': 60, 'purple': 90, 'black': 135];
if(contains(directions, first)){
  direction_color = first;
  degree_color = second;
} else {
  direction_color = second;
  degree_color = first;
}
if(!contains(directions, direction_color) || !contains(degrees, degree_color)){
  keep_going();
} else {
  turn(degrees[degree_color] * direction[direction_color]);
}


Can you identify this fencer Can anyone identify this hair piece and head? I did a search for moustache on Bricklink and couldn't find it.

The head is
part # 3626bpx129 : Minifigure, Head Moustache Black Bangs, Striped Sideburns, Cleft Chin Pattern - Blocked Open Stud

Hair

Part# 40251 : Minifigure, Hair Female Mid-Length

The rapier (sword) is from Brickarms


RCX 2.0 Firmware downloaded successfully but "Run" does nothing I recently was able to install RIS 2.0 for the first time since I just got a 32bit Windows 7 machine.

I got the IR tower to download the firmware to the RCX 2.0 and it showed exactly the same screens the guide showed, but when I got to the point where I test the motors, I found that the "Run" button does nothing.

I tried installing the firmware 3-4 times and still have the same problem, so I'm assuming the RCX itself has a defective Run button.

Does anyone know what's possibly going on? All the other buttons work, they beep and change the screen when pressed, nothing beeps or happens when Run is pressed.

Could be the button indeed. These buttons are conductive rubber pressing on the circuit boards integrated contacts. Might need some cleaning there...

Disassembly of the RCX is not easy but can be done. You have to remove the screws in the battery compartment, then pull slightly to disengage and remove the black IR front. Once this is done, you can pull out the PCB and battery case from the top cover. Important note: the PCB is connected to the battery case through metallic blades that can easily bend and no longer make contact. So when you pull the PCB+case, you must pull on the PCB itself, not on the battery case.

Once done, you can clean the button area with alcohol and/or swap buttons to hopefully repair the Run button ("View" button is useful, but not mandatory...).


LEGO 3069 tile 1x2 (dark?)grey with red and gold pattern and with yellow and white pattern Does anyone know the exact names of the tiles or which set they belong to?
Gold and Red

Yellow and White

The first tile is Tile 1 x 2 with Groove with Copper and White Circuitry, Red Rectangle and 4 Squares Pattern

Appearing in these 10 sets.
It looks like yours is Dark Gray.
The second tile is Tile 1 x 2 with Groove with Vehicle Control Panel Pattern

Appearing in these 82 sets.
It looks like yours is Dark Bluish Gray.


What are these two Lego parts? I want to order these 2 missing pieces but I don't know the name of them, can anybody help? What are the part numbers?

These parts are:

Item No: 2412b : Tile, Modified 1 x 2 Grille with Bottom Groove / Lip

and

Item No: 6266 : Leg Skeleton


Robot Inventor 51515 - PIN request when connecting via Bluetooth Just received the item 51515
Managed to connect the Mindstorms controller via Bluetooth from mobile without any problems. Great!
Next step, connect from PC.
When I connect from my Windows machine I get Bluetooth PIN prompt.
What PIN should I put in?

I removed the brick using Windows Bluetooth panel. Then once again readded the device using Lego software. And this time it did not ask me for the Bluetooth PIN.


Making a hexagon with plates Do any of the wedge/wing shaped plates have the right angle to make a true hexagon or equilateral triangle?

If not, is there any way to make a regular hexagon using plates?

(I know they can be made with Technic struts and connectors, see this BrickEngineer post for some good examples.)

None of the existing wedges have such angles as they are based on integer numbers for the sides. The closest angle you'll find is probably the 2x4 one:

But even that one is about 3° off (63,43° if I remember enough math), so if you place the 2-length sides of 6 of them on a nice hexagonal shape, there will be noticable gaps at the corners.

In short, if you want to build an hexagon-shaped surface without gap, it probably won't be possible.

However, if you want an hexagonal frame for a particular structure, you can use plates the same way you would use Technic beams and get the same results.

Also, the following modified plates could help, as they feature proper angles:


Steer with the LEGO Mindstorms EV3 In my workshops I get asked regularly, what the turn option of the default steering block means (see the image).

Obviously, if the turn option is set to 0, the robot is moving forward. A positive value is turning right, a negative is turning left. So far, so good.

I looked in the source code and found a programming scheme I tried to visualize. A large comment within the code describes the process as follows:

  Speed [-100 .. +100] is move forward or move backwards  Turn ratio
  [-200 .. +200] is how tight you turn and to  what direction you turn

  0 value is moving straight forward
  Negative values turns to the left
  Positive values turns to the right
  Value -100 stops the left motor
  Value +100 stops the right motor
  Values less than -100 makes the left motor run the opposite
  direction of the right motor (Spin)
  Values greater than +100 makes the right motor run the opposite
  direction of the left motor (Spin)

So the turn ration is multiplied by 2, because as a user we can just put -100 <-> 100 in there. I then used this code to calculate some values:

for (var i = -100; i == 100; i++) {
  turn = i * 2;
  if (turn >= 0) {
    motorB = speed;
    motorD = speed - turn;
  } else {
    motorB = turn + speed;
    motorD = speed;
  }
}

If I visualize those values, I get the following image for speed 100:

That's fine. You can see the real turn value (the ones we as a user can set) and the calculated speeds for two (virtual) motors B and D. I tried this with the educator model and it works perfectly well.

But when I use the same code for another speed value (33), I get motor outputs that are too high in my opinion:

The Motors will have values over +100/-100. Is there a threshold in the code and the motor outputs will be cropped?

Did someone else dig into this? Did I made a mistake?

P.S.: I love such things. If someone is interested in doing more if this, just ping me. :)

I can't say that I understand your problem, but maybe this link will help EV3 Move Steering Block Explained

If you are asking about how the steering parameters relate to how much the machine will turn, then that is going to depend very much on the geometry of the machine: wheel diameter and wheel separation.


How well does the new interior lighting system intergrate into a new build? I enjoyed the interior LEGO lighting I saw at Brickcon 2011. How does the lighting system affect the fit of the LEGO elements involved?

Considering the new PF lights are more compact at the point where the light is, I would say it's easier to integrate in creations. They do have a big block on the cable where the two lights are separated, but that leaves you more liberty compared to previous 9V lamps for which you had to have the cable connector on the lamp itself, which took quite a lot of space.

As such, you may be able to fit PF lights in tighter places, and have less constraints on the orientation (I'm thinking ceiling light with the bulb directed downwards, for example).

By the way, that's an area where a lot of LEGO fans are more willing to toss purism aside and use their own leds and cabling, which can easily be done without damaging a single brick, takes less place, and usually costs less.


Measurements (LDU) of Lego tracks Set 151 I have an old set of 7851 curved tracks.  I want to use the outer tracks (the ones with the bumpy surface).  If I was to put one end down on a baseboard so that is tangent/parallel with the grid of studs, how many LDU in the X and Y direction would the other end be?

I'd also like to the know the X, Y cartesian coordinates (in LDU) of the middle 2 slots as well.

Well, obviously one way to measure that would be empirically - you have the tracks, you have the baseplates...

As for the maths, let's see... a full circle of these tracks has a diameter of 5 straight tracks as measured from the centre of the sleepers, that translates to 80 studs. The radius is 40 studs, or 800 ldu.

The outer, ridged track, is 2 to 3 studs further depending on which border you consider (and assuming you want borders instead of stud positions). So the radii for the border of that piece of track are 840 and 860.

So, assuming the track circle is centered around (0,0), and using the usual way of considering circles in math (counterclockwise from (1,0)), your first piece of outer track starts at (820,0) and (830,0).

There are 16 segments of track to a full circle, so the angle for one segment is 22,5°, or pi/8. So the end of your first track part is at (840*cos(pi/8),840*sin(pi/8)) to (860*cos(pi/8),860*sin(pi/8)), or (776.06,321.45) to (794.54,329.11)

Expanding further, you get the following segments for the short border of the outer track:

(840.00,0.00)-(860.00,0.00)
(776.06,321.45)-(794.54,329.11)
(593.97,593.97)-(608.11,608.11)
(321.45,776.06)-(329.11,794.54)
(0.00,840.00)-(0.00,860.00)
(-321.45,776.06)-(-329.11,794.54)
(-593.97,593.97)-(-608.11,608.11)
(-776.06,321.45)-(-794.54,329.11)
(-840.00,0.00)-(-860.00,0.00)
(-776.06,-321.45)-(-794.54,-329.11)
(-593.97,-593.97)-(-608.11,-608.11)
(-321.45,-776.06)-(-329.11,-794.54)
(0.00,-840.00)-(0.00,-860.00)
(321.45,-776.06)-(329.11,-794.54)
(593.97,-593.97)-(608.11,-608.11)
(776.06,-321.45)-(794.54,-329.11)

Hopefully that makes sense. Watch out, these are the coordinates of the borders; for the coordinates of the studs (that is, the center of the studs, which I think is more interesting, but I don't know what your goal is) we'll have to use a radius of 850, and move 10 ldu along the tangent to find the stud. So to find the stud after the segment, we'll do (850*cos(pi/8)-10*sin(pi/8),850*sin(pi/8)+10*cos(pi/8)). For each segment N starting from 1, the studs are as follow:

start stud: (850*cos((N-1)*pi/8)-10*sin((N-1)*pi/8) , 850*sin((N-1)*pi/8)+10*cos((N-1)*pi/8))
end stud: (850*cos(N*pi/8)+10*sin(N*pi/8) , 850*sin(N*pi/8)-10*cos(N*pi/8))

End the two studs in the center of the track are basically and end stud if the angle was pi/16, and the start stud of the next track, or:

first middle stud: (850*cos((N-1)*pi/8+pi/16)+10*sin((N-1)*pi/8+pi/16) , 850*sin((N-1)*pi/8+pi/16)-10*cos((N-1)*pi/8+pi/16))
second middle stud: (850*cos((N-1)*pi/8+pi/16)-10*sin((N-1)*pi/8+pi/16) , 850*sin((N-1)*pi/8+pi/16)+10*cos((N-1)*pi/8+pi/16))

The four studs of the first part of track are thus at coordinates:

start stud: (850.00,10.00)
first middle stud: (831.72,175.63)
second middle stud: (835.62,156.02)
end stud: (789.12,316.04)


Part assortments for creative building I've been shifting away from collecting sets to doing more MOC building. I also recently moved and I'd like to reduce the overall size of my LEGO collection. I'm trying to decide which parts I'd like to get rid of and which parts I'd like to keep.

I'm interested in keeping large numbers of versatile parts while selling off parts that tend to serve a single purpose. I'm hoping to find example part assortments (not necessarily official sets) that are most useful for MOCs and rebuilding.

To explain what I mean, here are two example sets. The first is the new Architecture Studio set:

The second is the Hobby Train set from 2007:

These both contain a good mix of pieces that can be reused in all sorts of models. Are there other sets, parts packs, or lists that provide a good platform for creative building?

It very much depends on how and what you like to build so personal recommendations are difficult. As you're new-ish to MOCing it may take some time to figure out what pieces you like the most.

That said, I'll offer a suggestion - I find 10230 Mini Modulars and interesting range of small pieces in various colours incuding some rare ones. Check out the inventory to see if it appeals to you too. I'd also suggest looking at the Creator sets in general.


Using motors to ring a bell? I would like to create a motor set up so I can use it to ring a bell inside a small tower. Since I haven't used any of the current LEGO motors was wondering what the group would suggest.

which motor to use.
which battery/switch to use.

What I need is a simple switch with a motor. Something that I can turn off and on with out much trouble.

LEGO Power Functions would probably be the most suitable option. You could use a PF M-Motor (8883) combined with a PF AAA Battery Box (88000) which has a two-way switch and is more than capable of powering four medium size or two extra large motors (each item sold separately).


Why does display output affects motors? I'm making a simple program with LEGO EV3 Education. It makes a little tank to follow a black line over a white-ish floor.

Here it is:

[]

This works very smooth: it makes the tank follow the EDGE of the line and substantially takes in account the amount of light the sensor recevies.
Black is 11, White is 75: if the light is near 75, then take the power of the B (left) motor higher than the C (right) motor. if the light is near 11, then take the power of C motor higher than B. Otherwise, make C and B power similar.

I want now to add some output on the display, like this:

The idea is: if B power is between C+10 and C-10, then show a forward arrow. else if: if B < C show Right arrow, else Left arrow.

Problem is that, adding this code, the tank doesn't move straight anymore! C and B motor ,on a stright line, alternate power making the robot zig zagging the line.

Why does an output operation on the display affects motors power?

Because it takes time to write to the display. The motor speed cannot be changed until the display blocks have finished and your loop repeats.

Try this instead... create a second loop in parallel to the first that handles the display. You will need a new logic variable to send information from the motor loop to the display loop.


Is this antenna a LEGO piece? I came across this piece while sorting:

It appears to be similar to 2569, but it's clearly a different part. 2569 doesn't have the ridges and has a spherical tip rather than the cylindrical one on this part. The parts are roughly the same length.

I didn't see the word LEGO anywhere on the part, so I strongly suspect this is from a knockoff brand, but I wanted to make sure before I remove it.

I've never seen that part until now, and it's certainly not in the antenna or bar bricklink categories. I'm fairly confident it's not LEGO.

However, it would be far more interesting to know what it is, but that's not easy to search. A few Mega Bloks parts have been catalogued, but your part isn't there either (I could only check categories bar, weapon and tool/gear before I got sick, though). Considering that database is far from complete, it doesn't mean it's not Mega Bloks, though.

Actually, I think there's a good chance it IS Mega Blocks: the antennas on the Repzyllian Trekker and the Gyro Fighter look very much like yours.


How hard is it to convert the new(ish) RC/PF trains to 9V? I have a HUGE investment in 9V trains (think many thousands of USD) and was wondering how difficult it is to convert the newer RC/PF train systems over to 9V motors? Do the 9V motors fit? Does the base have space for the trucks? Is it even worth it (keep in mind, I hate batteries)? Converting the 12V trains to 9V was rather easy.

I haven't ventured out to purchase a set yet (even though they've been out for a few years now -- I'm lazy and cheap I guess) because they're all rather expensive (as we know), so I have not been able to check myself.

The PF train motor has the same size and shape as the previous 9V Motors, and a lot of people are happily substituting one for the other.

The Emerald Night, however, doesn't use that motor, so there your job will be much more tricky. Usually people change the tender to add two 9V motors there, but the wheel train of the engine tends to derail fairly easily if pushed that way (I strongly suggest you read RailBricks issue #7 for tips on how to make it run smoothly)


How to make a church bell I'm planning a scene that includes a church bell. It's will need to fit into roughly 10X10X6 space.  It doesn't need to actually make any sound but the ability to swing a bit would be nice.
Here's the image from the scene

I figure I can use a bar, some clips and some stoplights to make the swinging part. Can anyone recomend some parts for the bell itself?

Look at the bell in the Lego kit for Big Ben (#10253). Building instructions are here (Step 276).

The bell itself is made from several round plates and parabolic reflector dishes. It's not hollow, but it could certainly be made to swing.


Stained glass windows on The Throneroom of Cedrica Can anyone explain how to make the stained glass windows in builds like The Throneroom of Cedrica?

I see that this popped up on HNQ, so I wanted to expand on shoover's excellent answer with a build showing one way that this could be put together for folks that may not be as familiar with LEGO elements as the Bricks community.

As was already pointed out, the key element here is the 2x2 turntable base without a turntable attached:

Here's how you might pair those elements with transparent 1x1 and 1x2 elements to build a stained glass window:

We leave a couple of 1x2 plates overhanging the back to provide attachment points.

Here it is from the front. Notice that we also add a couple of 1x1 plates on the front side to make the connection points flush with the rest of the window:

Now we can build a frame to trim this out and create a nice looking window:

We can then attach our window using the attachment points that we left for ourselves in the back side of the Erling bricks:

Note that I'm not trying to replicate the exact techniques used by the original designer, but this does show one way to get a similar look. I've added the parts list on Rebrickable if you want to see exactly what I used and build this yourself.


How to update item prices in a Bricklink store? I have a BL store in which I have parted out a huge collection of LEGO sets. During the part out I set the item prices so that they match the average on BL. However, after a while, I noticed that due to the price changes, some of my items became significantly cheaper or more expensive than the average. Neither of them is desirable. Is there a way to update the pricing of my store including all items to match the current BL average prices?

The easiest way is to download and install Brickstock (www.patrickbrans.com is the site it is located on AFAIK), pay for the upgrade to the full version ($20 via paypal) and then download your entire store inventory, do ctrl-A ctrl-G which downloads the current prices, and use the “update inventory in bricklink” option from the File menu to set the new prices.


What set are these minifigs from? What are their names? Can anyone tell me what minifigs these are?

These look to be Mega Bloks Dragon figures.

The Vorgan (orc) is from the Krystal Wars era, which introduced the Vorgans and had Vorgans with brown vests. I can't find the set that fellow is in right now, but I found a future set with a look-alike in a blue vest where is name was Gohrgroc. The shield isn't used by the the Vorgan (orc), but is used by the Norvagen (blue armored guys not seen in the OP's picture). The Norvagen and that shield with the dragon head on a blue background are also from the Krystal Wars sets.

Here's a look at one of the sets in that line, with many of the names visible:

I've also found this video which shows most of the Krystal Wars figures, if not all, but unfortunately it's not tied to names or sets. Your Vorgan with the large underbite, as are your golden Draigar with horns up and forward, and the shoulder strap that goes across their torso (upper-left shoulder, to opposite waist, clearly visible buckle).

There's a possibility these figures are all from the Draigar Castle set, but the instructions for that are hard to track down and confirm. Mega Bloks has a very poor list of instructions on their support website (where they don't use the same names as available online, or even the same set numbers in some cases, and many sets appear to be absent).

Here's a link to the relevant instructions part for Draigar Castle. Right now, the host Photobucket is down so the link won't work, but it should in a few hours:

http://s935.photobucket.com/user/bloksforum/media/Instructions/9898/9898-03.jpg

For the record, I own a small collection of these figures/toys, that I inherited from my brother (I've never bought a MB toy myself). Unfortunately, I don't have the instructions or boxes/tins they came in, so I can't help narrow down the suspects with my own stock.


No response when controlling the Mindstorms EV3 brick over Bluetooth I am trying to control the EV3 using direct commands over a Bluetooth connection. There are no issues pairing the brick with a PC or phone, and opening the serial connection works fine, but sending a direct command such as playing a tone with

0x06 0x00 0x00 0x03 0x0B 0x02 0xF4 0x01

does not produce a tone and does not provide a response on the serial connection, even though the telegram type byte requests it.

I have tested direct commands using two different serial terminals on OS X and Windows 7, as well as an Android app made for this purpose and writing the bytes using my own custom program, and all of these give me the same results. However, the official Robot Commander app does work.

Are there any special connection settings needed for commands to succeed, or any common pitfalls that I might have fallen into? I have read the developer documentation and didn't find any glaring problems.

Using the documentation from here, here, here and here, the command for playing a tone should look something like this:

0x0F, 0x00,            // size of message = 14 bytes
0x00, 0x00,            // message counter = 0 [can by any number]
0x80,                  // command = DIRECT_COMMAND_NO_REPLY
0x00, 0x00,            // 0 bytes for global variables, 0 bytes for local variables
0x94,                  // opSOUND
0x01,                  // CMD = TONE
0x81, 0x32,            // VOLUME = LC1(50) [50%]
0x82, 0x0B, 0x02       // FREQUENCY = LC2(523) [C5]
0x82, 0xF4, 0x01,      // DURATION = LC2(500) [0.5s]


LEGO Master Builder Academy instructions My kids picked up a few LEGO sets from the Master Builder Academy series recently that do not come with instructions in the packaging. According to the support team at LEGO.com this series was discontinued in 2011 and no electronic copies of the instructions were ever produced by the company. We are looking for instructions for 20201, 20204, and 20205.

I have googled quite a bit and searched several LEGO fan sites but have been unable to find any scans or other digital copies of the instructions for any of these sets.

Does anyone have or know where to find these? Thanks very much!!

You can find the instruction booklets on BrickLink. They only costs a few dollars. They are not just about instructions. They include a whole curriculum for systematically learning advanced building techniques and building concepts with lots of information, seed ideas, alternate builds, etc. Here are the listings for the for LEGO Master Builder Academy booklets: https://www.bricklink.com/catalogList.asp?catType=I&catString=764


Looking for empty LEGO boxes for 6389 Fire Control Center and 6669 Diesel Daredevil I'm looking for empty LEGO boxes. I need two: one for 6389 Fire Control Center and one for 6669 Diesel Daredevil. Where could I find them?

You can buy boxes for most sets from Bricklink.com. For example, there are world-wide three sellers of the box for set 6389. Unfortunately, getting a box for such an old set will set you back $40-$50, excluding (international) shipping.

For set 6669 there are currently also 3 sellers, with prices ranging from $5 for a severely damaged box to $30 for boxes in good condition, all prices excl. shipping.

Of course there are other places to look, such as EBay or local classified sites like Craigslist in the US, but chances you find one of these boxes there are minimal. Bricklink (or its competitor BrickOwl) are your surest bet.


Arduino-izing LEGO Technic - and now I need some ideas for the Lego Service Truck 8071 I am starting a project - Arduino-izing LEGO Technic - and now I need some ideas for a car / vehicle to choose.

This project starts out as a quest to find a way to combine the ease of LEGO Technic chassis building with cheap commodity electronics to motorize and remote control it.

I was looking for a vehicle that is able to work for this. This could be a simple chassis: https://www.instructables.com/id/Build-your-own-Custom-Arduino-Remote-Control-and-L/ https://www.hackster.io/Notthemarsian/take-control-over-lego-power-functions-ee0bfa https://www.instructables.com/id/Raspberry-Pi-Remote-Controlled-Car-1/

This should be a part of a robotics workshop and therefore I need a LEGO-based platform for younger kids who grew up with Lego but cannot afford to spend hundreds of dollars to buy power functions, LEGO motors, IR remote, and EV3. Thanks to numerous examples on the net and several and Youtube tutorials on integrating Arduino with LEGO, I will try to start out with an interesting example.
Starting point: the kids should be able to complete this project with a small budget and I hope to incorporate this into my robotics workshop in the future.
The main thing is, I need to have the rear axle to be attached to a single N20 motor to move the kart forward and reverse via a TB6612FNG motor driver. Front steering can be controlled by an SG90 servo motor.

i have chosen the Lego Service Truck 8071 - see here:  https://www.lego.com/de-de/service/buildinginstructions/search?initialsearch=8071&ignorereferer=true#?text=8071

Remote control should be able to be accomplished by a cheap IR remote/receiver solution based on

Arduino
Zigbee
Bluetooth

I understand that the IR remote hardware (and the method) is pretty hard part to implement and learn about a remote control system so it was a perfect option for this car.

Since this is just a proof-of-concept project and the design follows function - I need to have an idea.

The main question is: How about LEGO Technic-8071 - the Service Truck?

guess that i can add the steering and motor with ease

many many thanks for all the hints -

So, after doing some research I think the most helpful solution I can offer is a picture of various techniques and a link to a straight-forward, budget friendly tutorial. I think trying to explain anything in depth would be tedious and vulnerable to misinterpretation. It also appears that super glue, hot glue, and some pieces to sacrifice/modify will be necessary.
The link: https://www.instructables.com/id/Arduino-izing-Lego-Technic-Go-Kart/
Pic:


Help identifying Lego Set from bags! I visited Toyrus in Paris recently and bought several lego sets for my son.  Mostly, Star Wars sets.  In each case, we brought the manuals and the cardboard boxes so that he could assemble them.  However, we also bought some sort of car / racing set, but we forgot to bring the box and manuals.  We have no idea what it is so as to find the instructions on the internet.  Are the photos below enough to identify them?  There are no numbers other than a reference to a 2011 set.  It´s 6 small bags, and four other small bags.  Not sure if the last one full of wheels is a separate set we bought just to increase the number of wheels.  Any help will be truly appreciated. Thanks, Pablo

The city people pack is probably 9348: Community Minifigure Set based on the clasic space minifig print.

The numbered bags are probably from 4635: Fun With Vehicles - that's based on the colours and the lime green/"bright yellow/green" cap.

I think the first 2 bags are from 6118: Wheels and Tyres. This set has the same number of the small (8x) and bigger (6x) yellow wheels


How can I make a brick-built wheelbarrow? I'd like to make a brick-built wheelbarrow to fit on a construction site that can be held by minifigures hands. I've seen prefabricated Duplo/Fabuland wheelbarrows as well as a new wheelbarrow in a 2012 CITY set which doesn't really appeal to me.

I don't mind using SNOT techniques and Technic elements. I've already tried making one out of Technic L shaped lift arms.

Brickshelf returns two interesting designs:

There's also a YouTube video showing yet another design which is quite simple yet elegant (although I would have put the 1x2 plate with handles under it, not on the side, but that's my own opinion.


Can anyone identify this octagonal dish piece for me? It seems like this piece would be named "Octagonal Dish 2 x 2" but I can't seem to find it on any of the usual sites. Is this named something else or is it not a real LEGO element?

I believe it's yet another MEGABLOKS part. You can see it on the top of 9321 Cyborian rover holding the yellow antenna, for example.


How did the LEGO 7862 Remote Controlled Decoupling and Signal work? I've never seen this set in person, although it appears occasionally in 12V Lego train system images. I've never seen it used, or described.

How did the LEGO 7862 Remote Controlled Decoupling and Signal 12V work? What is the 'Signal' component of the decoupler?

It basically forces the coupling magnets to separate via the pins pointing downwards from the magnet holders:

Here's a demo.


Boosters from set 71214 Benny don't fit The booster pieces don't fit into their place on Benny's Dimensions set (71214). I'm talking about the bigger booster in the middle.

This seems to be a really common problem, but is there a fix?

I experimented with several different "rocket" pieces (3963) and both variations of the "tap" piece (4599a & 4599b) despite the set listing only the "b" variant, and could not replicate the issue. There obviously had to have been a "bad" batch (or "fault" as mentioned by TheBrickBlogger) of one of the two pieces that unfortunately made it to some customers.  The simplest solution, if you don't have any extra parts of this type, would be to put a tiny piece of paper or tape on the tip of the nozzle before inserting it into the rocket piece.  Another suggestion, if you have a couple of 1x1 round plates with open studs (part #85861), is to insert these into the rocket holes to hold the nozzles in place.  There is just enough room for them:

Also, as mentioned above by TheBrickBlogger, Lego would probably be more than happy to replace any defective parts you were to encounter. Even though this is an old question I hoped maybe an answer could still be useful for someone with a similar piece problem. (In case anyone noticed, I didn't have any of that piece in blue for the nose piece)


Trying to get a modified traffic signal challenge worked out The challenge is for a robot to go around the perimeter of a rectangular field and execute 90 degree turns when it gets within 4.5 inches of a wall.  Simultaneously, if the bot encounters a red flag, it needs to stop until the flag color turns green.  At that point, the arm holding the color sensor needs to dip to avoid the traffic signal, and once it is passed, continue on it's way.

I have tried running two threads, one where the bot encounters a flag (which I have constructed a switch for cases red and green), while the other is where it encounters a wall.  I think these two threads need to be encased within an infinite loop, but I can't seem to make it so.

You can use finite state machine. In this case you will have these 5 states:

RUN

Action: turn on the motors for moving straight

Transition to state TURN in case of event: ultrasonic sensor detects obstacle closer than 4.5 inch).

Transition to state WAIT in case of event: color sensor detects red color

WAIT

Action: stop motors

Transition to state CONTINUE in case of event: color sensor detects green

CONTINUE

Action: move forward a bit while avoiding the flag

Transition to state RUN immediately.

TURN

Action: Turn the robot 90 degrees right, increment the rotations

Transition to state STOP in case of event: rotations = 4

Transition to state RUN in case of event: rotations < 4

STOP

Action: Interrupt the program.

Here is the code I've just scratched without a testing, let me know if it works:

You can enhance the state machine to check for the flag during rotations, too. :)

You can learn this robotics topic from the great book by Daniele Benedetelli - LEGO MINDSTORMS EV3 Laboratory.


What version of Lego Digital Designer has all the parts that LEGO ever added? I would like to know what version of Lego Digital Designer has all the parts that the Lego company has ever added to the program, before the program was discontinued. I was able to find more parts from someone on Eurobricks forum but I still need more bricks.

I believe that the last version that had a complete set of elements was 4.3.11, however that has dependencies on Adobe Flash, so will likely not work on most modern systems that have now removed Flash.
The last release, 4.3.12 has a known issue with missing parts. However you can use the parts library (Assets.lif) from 4.3.11 with 4.3.12 - this can be extracted from the installer if you open it with an archive explorer (i.e. 7zip or similar).
Bear in mind that:

To see all the parts, you may need to enable "Extended Mode" (View | New themes | extended).
LEGO Digital Designer is no longer actively supported. However The LEGO Group have purchased the team behind Studio, which is actively developed and has new parts regularly added.

Edit to add:
Glad you've managed to get it working in your preferred version. I'm not aware of people adding more elements to the official library files, but I've not really looked for it.
Whilst we can't say exactly what The LEGO Group will do in the future, they did say when they acquired BrickLink that:

The LEGO Group is planning to support and evolve Studio and will review opportunities for both services following the closing of the deal.

They also released a video last December (2020) where they updated on the future of both BrickLink and Studio.

In addition, we're going to upgrade the Studio software every month to improve the user experience and enhance it's performance.

Finally, as a quick test, I was able to find the Fright Knights Witch and Bat Lord heads and torsos fairly quickly in Studio:

Others are likely available.


Access WeDo on OS X from a real programming language I'm trying to talk to the WeDo USB interface from Python or really any real programming language.

I tried the clever WeDoMore library, but can't get it to bind the WeDo. I think this is because the WeDo is a HID device and the built in Mac OS HID driver binds to it before libusb, a dependency of WeDoMore, get's a chance to. But, my understanding is a little shaky.

The developers of WeDoMore are quite helpful, but don't use Macs themselves.

Any hints that would get me talking to the WeDo would be greatly appreciated. Scratch works, but I'm looking for a more standard programming environment.

It is possible to drive the WeDo from Python on a Mac, without a kext.  I've only tested motors since I don't (yet) have the other sensors.  You need to access the USB HID device directly.  There are a couple of prerequisites to install:

cython-hidapi, which itself depends on
hidapi; homebrew can install that for you.
cython likewise

You'll likely want XCode and friends installed to be on the safe side.

There are a number of forks of cython-hidapi available so your mileage may vary depending on which version you use. I don't remember installation being problematic.

Once those are installed and your WeDo is plugged in you can do something, at a minimum, like:

import hid
import time

# vendor id, product id:
dev = hid.device(1684, 3)

# turn both motors on
# HID format is reportID, message type, data1, data2, ...
dev.write([0x0, 0x40, 127, 127, 0x0, 0x0, 0x0, 0x0, 0x0])

time.sleep(1)

# turn them both off
dev.write([0x0, 0x40, 0, 0, 0x0, 0x0, 0x0, 0x0, 0x0])

The changes to get WeDoMore to use hidapi instead of generic usb on a Mac don't look to be too onerous.  If I manage to get something committed I'll update my answer with a link.

[Edit: I've committed a fork of WeDoMore that adds support for motors on the Mac here.  Again, I'll update if the pull request gets accepted]

Small side-note: The WeDo can also drive 9v motors with the correct converter cable.  I think it's possible to read the RCX sensors as well, but mild soldering may be required (see, e.g. here for a proof of concept).  But if the WeDo can be fooled into reading the devices then Python can be used with those other sensors.


Lego Duplo Train Track Switcher washable? / Best way to clean them? I've found some pretty old Lego Duplo train track parts, that I'm looking to sell on Ebay.

As these are pretty old and caked with dust, I wanted to used my usual method I usually use to clean all kinds of Lego parts: Put them in a duvet cover with a zipper so they don't go everywhere, and put them in the washing machine, and wash without any detergent and no spin cycle.

Afterwards I take them out of the machine (thanks to the duvet cover I can take them out just like a bag) and spread them on my terrace to leave them in the sun to dry.

As these track switchers have metal springs in them (at least I think so, judging based on the sound when moving the red thing) I was not sure, if they were just normal steel or stainless. Does anyone of you know about this, or know a way to open them without destroying them?

According to this page it is glued together and can not be opened without damaging the part

You are correct about it containing a metal spring

I would just wipe it with a slighty wet towel


How can I create a simple steering mechanism for a car? Just curious about this. How can I create a simple steering mechanism for a car? Either motorized or non-motorized solutions are fine; just not overly complex.

The most common I've seen is rack and pinion:

Essentially you have two parallel beams with one fixed to the car's chassis. The other bar moves horizontally which changes the direction of the wheels. Attach some gears and you can hook it up to a steering wheel.

The steering technique has been used in the Whirl N' Wheel Super Truck (5590)
 set. The instructions for the set show how an similar rack and pinion mechanism.


How does cleaning yellowed Lego bricks affect their clutch power? Will cleaning yellowed bricks (via the retr0brite solution) decrease the clutch power of lego bricks?

I've also heard that certain colors of embellishments on the minifigs or bricks do not hold up well to this solution, is there any definitive list of colors that do/don't hold up well? I have some old white bricks with red and black printing on them that I'd love to unfade if it won't wipe out the lettering.

The retr0brite method only affects the surface of the brick and does not affect the clutch power.

I have used the method on several printed bricks. I have noticed the black printing will start to fade if the bricks are left in the solution for a long time. I have not noticed that it affects other colors as much as black, but this may be because the fading of black ink on a white or yellow background is more obvious. I have never seen the treatment completely erase any printing.

The length of time it takes the solution to start breaking down the ink is going to vary with the strength of the solution, the time in the solution and the amount of UV light. You can control the first two variables, but if you are using sunlight to provide the UV it is difficult to gauge or control.

The easiest variable to control is time. I would leave the bricks in the solution for perhaps an hour at a time, then take them out, rinse them off in water and dry them. Keep one of the yellowed bricks as a "control" against which you can compare the treated brick to get an idea of how much color has changed. Repeat as necessary until the brick is back to the color you want or you notice the ink beginning to fade.

Check the color of the bricks indoors. I use the sun on my front porch to provide the UV light when I'm soaking bricks, and I have noticed that bricks that look nice and white when I'm out in the bright sun will still appear yellowed when I get them inside.


Mystery 2x14 grey brick - cannot find instructions with this piece mentioned I have a bunch of LEGO bricks from the years 1975 - 2016. There are a lot of obscure pieces in my collection, but this piece is so obscure that I have no idea what it goes to. If anyone can help it would be much appreciated.

This is item no 812

Train Level Crossing Center Rail Cap Insert
2 x 14 x 2/3

made for item no 813, the railroad crossing.

(source: bricklink)

It replaces the 12V straight insert (i.e. it closes the middle gap) when using a 4.5V train system.


Why are different ID informations printed in the inside of the same sort of bricks? While sorting old bricks I observed that the inscriptions printed inside show a different coding. As you can see the outside it is always a ordinary "1x2 tile with groove in good old Light Gray (item number 3069)". The inside instead appears very different.

Reading from left to right it says:

15; (c) LEGO; 032 #
LEGO; 3 #
(c) LEGO; 16; 35; 3069 #
8; (c) LEGO; 032 #
LEGO;  1 #
3069; 36; 17; (c) LEGO #
5; LEGO; 3; 1 #
LEGO; 11; pat. pend. #
LEGO;  11 #
3069; 36; 9; (c) LEGO

Why is that so?

You can also see that most of the bricks got on one half of the inside a yellowing. It seems that the effect is not only accruing on the surface but really eating its destruction through the material which I was not aware of.

On newer pieces (maybe also the newest of the ones you show), there's a number identifying the mold and one identifying the position in the mold, allowing LEGO to trace a problem all the way back and examine the mold if a high number of errors seem to come the same mold.


Which is the largest U.K. LEGO shop? The LEGOLAND Windsor claims to have the largest U.K. Shop for LEGO, but the Leicester Square store claims to be the largest LEGO shop in the world. Which is the truth?

The LEGO Store in Leicester Square which opened in 2016 has an area of 914sq m

(Source: Evening Standard, Telegraph)

The LEGOLAND Windsor Big Shop is 'one of the UK's largest shops for LEGO' according to their website. In 2015 the website stated the store was '... the UK's largest one-stop shop for LEGO'. It appears as if the Leicester Square store has taken over.

The LEGOLAND Big Shop is operated by the parks owner Merlin Entertainments. As it is not an 'official' LEGO store it does accept VIP cards or have a standard pick-a-brick wall.


Is there a microphone that works with Mindstorms EV3? I'm planning to program my EV3 robot to do voice chat over VOIP using ev3dev and a Debian program. Is this possible? Are there microphones known to work with EV3, and has anyone had experience using them?

Sadly, there isn't much info yet.

Current options for audio are:

USB Sound Card
BlueZ 4/Pulseaudio 4 (BlueZ 5/Pulseaudio 5 supports
A2DP only)

The number of devices that have been tested and documented is extremely limited, but at least one has been confirmed to work. The non-bluetooth solutions that have been tested successfully are the following.

Tested and confirmed adapter chipsets:

C-Media Electronics chipsets (Example)

Tested and confirmed microphones:

Logitech C170 webcam built-in microphone

More info in this github issue for ev3dev


What is the best way to create an authentic weatherboard wall? I am working on a house where I want to create a weatherboard look for the outside walls.  I'm not certain the best way to go about this.

Currently I'm using the horizontal side of a 1x2 profile brick:

Which gives the following appearance:

I am wondering though if there are any better techniques to create the weatherboard look:

It seems that the 1x2 profile brick has its ridges roughly twice as dense as a true weatherboard exterior.

One advantage of these profile bricks is that their reverse side gives the interior a VJ (tongue and groove) look, which is the interior look of the house that I am trying to model.

However, the lack of anything larger than 1x2 and the overly dense ridges means that I'm leaning towards looking for other options.

One option would be to use the relatively new bricks with masonry profile:

If you aren't aware, the reverse side of these bricks includes the horizontal lines but leaves out the vertical ones. This allows you to create something like this:

This solutions provides the advantage of less dense horizontal lines, but being that this is a newer part, it also really limits your color selection.

Your pictures make it look like you are trying to build a white house, which is currently impossible using this part as it isn't available in white. The best that you could do is light gray, which is what I used in my example.

There is a 1x4 version of this part that would make construction much easier and sturdier, but it's only available in medium dark flesh at the moment:

This construction also leaves you with a brick pattern on the inside of your wall. It doesn't sound like this is what you want. One solution would be to create a double wide wall, but that may not be feasible in your case.


Which set are these 3 LEGO bags from? I've got 3 bags.

On the bag 1 it says 529r9
Bags 2 and 3 says 629r9

Is there any way to figure out what set are these bags from?

It's Harry Potter set 75947 (Buckbeak's rescue).


What is considered the most valuable LEGO set? Which Lego set is considered to be the most valuable set to own?

I'm not talking about the most expensive set, and clearly it has to be out of production already, but when trying to collect complete sets from LEGO history, there must be one or a group of sets that are prized possessions for collectors.

Which are they?

I believe it's the Ultimate Collector's Edition Millennium Falcon (10179).

With a $500 MSRP, it was already one of the most expensive sets available when it launched in 2007. In 2012 it is rare to see it for less than $1500 used but intact, and closer to $2000 if you want it new. There may be some smaller sets that have a greater percentage gain (a set that was $2 going to $20, for example), but I suspect at $2000 and a $1000-1500 difference, this is the largest magnitude.


Suitable arched bricks for building a bridge I'm working on a LEGO project with my son and we want to include a bridge. However, I cannot find individual arch pieces that would work for a bridge.

This sounds like a fun project! There are lots of options available for arches. It might be helpful to know a bit more about what you are looking for. If you are trying to build an arch bridge such as this:

The 18838 arch or similar might be a good fit. These can be purchased on Bricklink or directly from LEGO fairly inexpensively.

If you don't have an easy way to get that piece or a regular arch piece doesn't meet your needs, you can get pretty good results emulating arches of any shape using inverted slopes (or regular slopes if you get clever). Here's an example brick-built arch by Tom Alphin:


Am I able to use the Chrome version of the Mindstorm software on a Windows/Mac laptop? We currently teach Lego robots as part of our Technology curriculum, but we are 1-to-1 in a BYOD environment. So we have all different types of devices the students use including Chromebooks, Windows and MacOS.
Is there a way a Windows (or MacOS) user can use the Chrome app version of Mindstorm software?
I keep getting a message to go do "Lego Downloads" to when I try to open the app in a Chrome browser.

LEGO Education has a new programming software called EV3 Classroom that will work on Windows, Mac and Chromebooks that can run Android apps. This is probably the best option for the devices listed but won't work on all Chromebooks. It is available from the LEGO Education download page.
The retired Chrome app only works on Chromebooks.
MakeCode could be an option too.


Bridge from just basic bricks? I teach an after-school engineering class using LEGO bricks, one of our classes has the students build a bridge.  Each student gets a custom set of about 150 2x4 bricks, about 300 2x2 bricks, and, if I'm feeling generous, about 15 2x8 plates.  Although I've seen many fancy bridges made with technic parts, I've never seen an awesome bridge made with just basic bricks.  I'm looking for a reference bridge to show the kids, after the build their own, what is possible.  So, show me the best bridge (either a link to someone else's bridge , or a photo of your own) that can be made with just basic bricks!

Scope note: Most people don't have this custom set of bricks, so links or pictures of any bridge that uses almost no rare parts and use almost no technics would be cool.

Background:

LEGO Bridge Page: http://lego.sparre-andersen.dk//Transport/Broer/

Arch from archive

Cantilever from archive

Big:  from archive

Sort of basic arch: from flickr

If you also want them to be aware of the solidity of their bridge, you may want to have a look at this contest.

Note that bridges made of stacked plates are much more solid than Technic ones.


How can I tell if my gold C-3PO minifigure is legit? I just bought a used gold C-3PO (not the 14k version, but the 10,000-made version). There are some places under the arms and on the right foot where there is no gold paint. I think that they are all like this, but I'm not sure. I'm looking for someone to verify that I didn't just get taken to the cleaners. I can still open an eBay case if I need to.

Yes, that sounds like the genuine article - LEGO was unable to chrome each part separately, so there are bare spots where you describe. Only the customs will have been made up of individually chromed parts.


LEGO model of USB socket? I am looking to make a LEGO version of my laptop. Is there a LEGO brick or set of LEGO bricks that would form a USB socket?

At a larger scale, a similar hole that includes an indent that can accept circular connectors, preferably 3-brick long for anchoring, for a true connection. But at that size, it would be roughly 3.2 times the size of a typical laptop.

For a tiny model, just do a 2 x 1/3 x 1 brick hole, into which a no-studs plate can be slipped.

If you are going for an actual socket that can hold a stick, sorry, but the end of the road is here, barring rubber piece use. A standard A or B type USB can't fit into LEGO proportioned holes.


What is the identity of this 4-wide car bumper part from a photo? Can anyone tell me what part this is?

It's [Part 50949] Plate, Modified 1 x 2 with Racers Car Grille


How much do bricks cost at the LEGO Store? I have never been to a LEGO Store, and I am hoping to go to one soon. I was wondering if anyone knew how much bricks cost at the LEGO Store? I want to buy some minifigs and some bricks. Do they sell the bricks by pound, or price per brick, or something else?

The most common way to buy bricks from LEGO stores is by filling up a PaB cup:

There are two sizes of cups and occasionally other containers that can be filled during certain promotions. The large cup is $15.99 USD and the small cup is $8.99 USD currently. This isn't advertized, but you can also buy bricks in the boxes that they are shipped to the store in. These are $100 USD.

LEGO stores also typically allow you to build your own custom Minifigs. These include legs, torso, head, headgear, and an accessory. These are currently 3 for $9.99 USD.


How many LEGO bricks exist in total? How many LEGO bricks have been produced in total? I'm asking only about real LEGO, not other brand's "blocks."

This article from Gizmodo puts the number at 400 Billion, but that was written in 2008.

The BBC from 2018 says "75 billion bricks are sold annually."

An answer on Quora puts the number at 600 billion sold.

I understand that the number sold, and number produced is likely very different, thus my sources are not particularity useful. So how many LEGO bricks exist?

It does not seem as if it would ever be possible to come to a definitive assertion—or even a sufficiently precise  approximation—of "how many LEGO bricks exists." For the English Wikipedia article "Lego" in the "Manufacturing" section informs,

  Annual production of Lego bricks averages approximately 36 billion, or about 1140 elements per second.

Although this quotation conflates "bricks" and "elements" thereby ambiguating whether it refers specifically to bricks or generally to any LEGO component, it nevertheless indicates that the number of LEGO bricks is indefatigably increasing. Thus, even if a total number of LEGO bricks in existence could be concluded, that number would immediately be inaccurate as a result of additional bricks continuously manufactured. Furthermore, as Eran perceived in the comments, LEGO bricks eventually disintegrate or become unidentifiable as LEGO; therefore, even if there were documentation of exactly how many bricks were produced up to any given time, it would still be infeasible to establish how many LEGO bricks exist because it would be extraordinary difficult to ascertain which individual LEGO bricks are currently in existence.


How to use the ultrasonic sensor on mindstorm NXT I've been struggling for some time on this. I'm trying to code the robot to move when the distance is above a certain integer and stop when the distance becomes lower than the certain integer. I'm coding in Eclipse Helios. My code is below:

import lejos.nxt.Button;
import lejos.nxt.Motor;
import lejos.nxt.SensorPort;
import lejos.nxt.UltrasonicSensor;

public class robot {
    public static void main(String[] args) {
        UltrasonicSensor us1 = new UltrasonicSensor(SensorPort.S4);

        System.out.print(us1.getDistance());

        if (us1.getDistance() >= 25);
            Motor.A.setSpeed(50);
            Motor.C.setSpeed(50);
            Motor.A.forward();
            Motor.C.forward();

        if (us1.getDistance() < 25);
            Motor.A.backward();
            Motor.C.backward();
            Button.waitForAnyPress();
    }
}

It's a little unclear from your question where this is currently failing, but I do see a couple issues with your code.

1. Your if blocks are probably not doing what you expect. You should include braces to conditionally run the block following an if statement. As written, all of your code executes all of the time. This is a tricky bug to spot, as it looks correct, but isn't. You probably want to change this:

if (us1.getDistance() >= 25);
    Motor.A.setSpeed(50);
    Motor.C.setSpeed(50);
    Motor.A.forward();
    Motor.C.forward();

To this:

if (us1.getDistance() >= 25) {
    Motor.A.setSpeed(50);
    Motor.C.setSpeed(50);
    Motor.A.forward();
    Motor.C.forward();
}

2. You say that you want the motors to stop, but it looks like you are actually reversing them. You'll likely want to change this:

Motor.A.backward();
Motor.C.backward();

To this:

Motor.A.stop();
Motor.C.stop();

Your code may still need some tweaking, but hopefully those two fixes get you back on track.


Do extra parts add to set's resell value? When I build a set I tend to keep the box and instructions as I noticed they add to the value of the set.
I also keep the extra parts in the box but I'm not so sure if they add actual value. My understanding is they are random so there is no way to confirm they are the original pieces that came with the set.
Is there any value in keeping them along with the set when selling?
UPDATE: Based on the comments I understand the extra parts are consistent and predictable. So I would have thought having extra parts in would make the set more valuable. In BrickLink generally the status of box, minifigs and instructions are mentioned. No mention of extra parts.
Am I correct to think it doesn't add value if we included extra parts?
Thanks.

Generally, I think it doesn't add much value. But it depends.
Some sets, like US version of 8284, have extra parts crucial for alternative model (aka B-model). So unless you include them, you are selling incomplete set. The inclusion of all parts to build all models is part of "complete" condition description on Bricklink. Extra parts excluded though.
Then again, new DOTS sets, which have random printed tiles, but the number of included items is the same. So if you are looking for particular print, it would be nice to have extra.
Sure, there's a ton of sets with quite generic extra pieces, that you may already have a ton of. And buyer may as well already have a lot of them. However, buying a used set with box, instructions, stickers/sticker sheet as well as extra parts is always nice, especially if it is older set.


Hidden Side Paranormal Intercept Bus, Ghost Video Game? The Hidden Side Paranormal Intercept Bus makes several references to classic LEGO sets and video games, like Rock Raiders and Bionicle.

I'm wondering about the game sticker featuring a ghost. It seems like it is also a reference to another LEGO game, but I don't know what it is.

Here's a picture I found of it, it's the purple sticker on the left.

Is this also a reference to a LEGO game?

According to the set designer for the Paranormal Intercept Bus set, Niek van Slagmaat, the released product contains 3 references in total, which he identified in a presentation at BrickFair Virginia 2019.

You can skip ahead to the 22:43 time to hear him talk about the sticker sheet and the references it makes, which are listed below.

Rock Raiders icon
License plate number GG 4940 (Rock Raiders set 4940 The Granit Grinder)
Bionicle video game (The Legend of Mata Nui, the unreleased game which leaked online shortly before the set was being designed)

He also identifies the purple sticker in question as a radar screen.

  I decided to just pick whatever Bionicle video game I could find and this one worked quite well so we ended up putting it on the secondary screen so while she's hunting for ghosts on this computer here using the radar she's also just playing some Bionicle game off on the side.

This confirms this screen is intended to represent the world in which the set takes place, and not reference another old Lego game.


Where is this round blue BIONICLE figure from with circular hands and a transparent head? Please help me identify this blue BIONICLE figure.

The set in question is 8562 Gahlok. It's missing the legs and parts of its head.


What's the most cost effective way to buy bulk LEGO bricks? I've found a couple places to pick up bulk LEGO, but they all have various issues.

Bricklink - I found their user interface confusing, clunky, and straight out of 1998. I'm aware of a couple of other questions here discussing alternatives to Bricklink and ways to optimize Bricklink shipping costs.
eBay - Fine for most things, but doesn't work when you need a specific brick in a specific color.
Pick a Brick  - They don't have ALL the bricks available.

Does anyone have a more effective and efficient way to buy bricks?

First off, as you mentioned, Ebay is not the greatest place on the net to get bricks. As you seem to be aware of, it is difficult to get individual bricks from these individual sellers. Having to pay separate shipping from various buyers plus the unreasonable prices can really add up.

Then there's LEGO Shop. Here, you can buy LEGO bricks directly from the LEGO company. You can individually purchase bricks from Pick-A-Brick, or buy their currently advertised sets. The downside to this is that they obviously do not carry discontinued sets, the selection in Pick-A-Brick is limited, and the prices are unsatisfyingly high, making the bucks add up quickly. Shipping times can be pretty quick and cheap, that is, if they're not currently having any difficulties with their warehouse. If they are, then orders can be delayed by a large amount of time, which has happened to me twice. I once placed an order there which took nearly two months to arrive.

Then, there's Bricklink. You seem to be aware of this website. I like it very much. It is, in many people's opinions, the best source from which to acquire LEGO bricks. The prices are cheap, it carries almost every piece and set ever released, (even discontinued ones) the tools for finding bricks are useful, and most of the people there are pretty nice. The interface is quite useful, you just have to be familiar with it. Once you get used to it, I'm sure it won't seem so "clunky" to you. For detailed help, enter the chat room. The people there are very nice, and will be happy to you point you in the right direction.
Shipping times vary depending on which area you buy from. Buying from within your country might generate shipping the speed of TLG on their best days. Bricklink, however, is much less likely to have technical difficulties as each order is just an individual seller sending something off to the post office, and has therefore generally been more reliable in my experience.


Purchase a list of LEGO parts If I have a list of LEGO parts (exported from LEGO Digital Designer or Bricksmith) is there an easy way to purchase all of the parts either on LEGO's Pick a Brick or on Bricklink?

I know that I can go through the list one by one and order the pieces but I was hoping that there might be some tool where I can upload a list and have all of the parts automatically added to my cart.

Doing this for Pick-a-brick (which sports an antiquated UI) requires some fairly advanced hacking. See this question. It's unfortunate that there is no simple interface for importing composite sets of bricks.


Can anyone identify this dark grey remote control and receiver with yellow and orange buttons? Does anybody have an idea where this remote control and receiver are originally from:

Bionicle manas set 8539.
Top part from your foto. Bottom one.


Are coloured bricks used by Set Designers recycled to make black bricks? I heard on a podcast of the Adam Savage Project that the master builders (designers of 'sets' of LEGO) are allowed to use as many blocks as they need to design a certain set. All of the bricks they use to design the sets are then thrown together, melted down, and made into black bricks as it is cheaper than resorting and less time consuming. Due to the pieces being used they are not allowed to be resold... Is this true?

Short answer: No.

Long answer: After searching around the web and finding nothing related to this subject, I fired an email towards LEGO Customer Service asking them this very question.

Today I have received this reply:

  Dear Adam,

  Thanks for getting in touch with us and sending us this question.

  I have investigated the case further with our LEGO® product specialist team and I received the following answer from them:

  No this is not true, the designers build the sets and then they have to get approved. If the set isn’t approved the bricks and sets stay out or on the designers desk, and the set is taken apart the bricks are used again.
  I hope this information will help to settle the debate.

  We want to make sure we're doing a good job for you, so you’ll always find the link to a four-question survey in our emails. Please tell us how we did today:

  LEGO Survey link

  Please let us know if you need anything else.

  Happy building!

  Ildikó
  LEGO® Service


What part in LEGO digital designer can be used for a tank track? I'm using LEGO digital designer to model a LEGO tank. I don't seem to find parts that can be used to make the tank track and the inside wheels; I found a "caterpillar belt" but no wheels that can fit inside the track.

There is a part called "caterpillar track", and unlike the belt the track requires wheels of different diameter to fit inside it. Again, I can see the wheel for the wider end of the track but not the narrower end.

Are there any parts that can be used for tank tracks at all? Or should I look for an alternative solution?

The caterpillar track and belt are both fixed length pieces.

I would recommend the more versatile #57518 'Technic, Link Tread Wide with Two Pin Holes'. The part can be used to make a track as long as long as you like.

The tread is compatible with:

#57519 - Technic Tread Sprocket Wheel Large
#57520 -  Technic Tread Sprocket Wheel Small


Identify "dark blue wing" Not sure even if it is a wing or maybe it is a fin or a stabilizer or completely something else:

I have three of them
Identical pieces and also top/bottom sides are identical
No ID nor any text/graphics on them.

That's Flag 5 x 6 Hexagonal (x1435). The lack of any numbers explains why "x1435" was used to catalog the piece, back in time when official part numbers were unavailable. Dark Blue coloured element was available in 6 sets.


Known quality control issue with 10234 Sydney Opera House? I have just completed 10234 Sydney Opera House, with one white half-shell (Bricklink: 41749 White Wedge 8x3x2 Open Right) missing.

Both the Bricklink inventory and the Lego instructions show 34 of 41749 and 35 of 41750, so this looks unusual.

Have I misplaced an element, or is this a known quality control issue with this set?

You seem to imply you built some of the structures symmetrically; however, by looking at the building instructions, I notice they are not: the subpart starting at page 37 of book 3 uses 7 wedges in total, while the opposite one on page 48 uses only 6.

While missing parts do happen (and are usually solved very diligently by the customer service, as said in other questions on the subject), it's always worth double-checking if the instructions were followed correctly, especially in such a huge model.


What LEGO set do these numbered bags of pieces come from? I found these bags in the attic any idea what LEGO set they belong to?

They are numbered 1, 3 and 5, but I don't know if they all came from the same set or not.

These bags don't seem to belong to any specific LEGO set.

First, they are filled very sparsely. Normally LEGO bags are filled with more elements than that depicted here.

Secondly, in bag #3 we clearly see a Plate 6X6 W. Bow in medium lilac:

And a Right Plate 3X8 W/Angle in bright yellow:

But these two parts have never been sold in the same set. These contain the lilac plate, and these the yellow plate.

So the only remaining possibilities are, in order of descending probability:

The bags have been opened and the contents changed (possibly resealed later)
These are not genuine LEGO products (but the bags do have "The LEGO Group" printed on them)
Someone at a LEGO factory has made a grave mistake


Which blocks are these with small round knobs? I have few blocks remaining from the block set I got as a kid. It's not LEGO bricks, but I also couldn't find which block type are these and who is making them. Does anyone knows from looking the images who is making these and if they are still produced so I can buy them.

Sorry if this is not right place to ask. Maybe you could point me to other place where I can ask.

I think this is Marklin plus,
a building system by Marklin which ran from 1973 till the end of the seventies

also see http://www.metallbaukasten.de/marklin/plus.html

thanks to the comment of Jan Windemuth for pointing me to Marklin


How does LEGO decide it needs a new element? Aside from the need to add licensed series specific pieces, how does LEGO decide it's time to introduce a new shape to the element palette?

This may not really qualify as an answer, but basically I believe designers are responsible for calling for new parts.

For each new part, a production cost is calculated, which takes into account a lot of factors. There were talks a few years back about how they had recently changed these rules, but they aren't public (to the best of my knowledge). What is more or less certain however is that an element which fits well in the system has considerably more chance of being accepted; that is, I suppose the calculated cost is lowered to reflect its usefulness. That's why a lot of recent new parts are just of the "it so obviously makes sense, why didn't they do that before"-kind (1x3 tile, 1x1 bricks with 1 knob,...).

So the designer willing to commission a new part for one of his sets will need to support that cost as part of the cost of his set, which is imposed to him. I guess there are much more rules than that (if multiple designers agree on a part, for example), but that's the basics of it.

Also, note that producing an existing part in a new colour follows the same rules to an extent. It's calculated cost is higher than an existing colour for that part.

To summarize: each existing part has an associated production cost which the designers must take into account when creating a set. Non-existing parts are similarly associated a cost, which is calculated according to a lot of rules/factors which aren't public.

Even the costs of existing elements show subtle variations: some colours are cheaper than others, for example; or older elements may be more expensive because moulds aren't optimized (one known case is the Technic axle 5 which is cheaper than the 4 one, because there are twice as many of them on a mould).

Last thing, more as an aside: the cost of the first part in a model is also higher than the next ones, because it helps production to have more similar parts. For example, 7945 Fire Station doesn't have any regular 1x2 red or white bricks - since they have 1x2 bricks with groove for the doors, they used these everywhere a 1x2 was required - even if no groove was needed. That way the number of different parts in the set is lower.

Edit: here is a very interesting video on how they prototype the new elements. Notice at the beginning of the video, the designer explicitly mentions he couldn't get the shape he wanted with existing elements, so he had to have a new one made. This was for a license set (cars), so again the decision in this case may be easier to take.


What is wrong with a Lego pneumatics system that won't go? I own a LEGO Technic Unimog U-400 (part number 8110) and have been very pleased so far with the performance of its pneumatic system. However, after storing for just a month or two (after a good 5+ months of hard use), the pneumatic actuators in the crane did not work, even with brand new batteries. I disconnected all of the hoses and felt that the actuators had more friction than they had previously had when the model was working well, which led me to oil them with vegetable oil, along with the pneumatic piston pump.

When I reconnected all of the hoses, switches, connections and tried it out, the second actuator (the one controlled by the middle switch) and the third actuator (the one that powers the claw) still didn't work, while the first actuator (the one controlled by the first switch from the left) worked as good as new. I have checked and double checked the connections. What is the problem
 here and how can I fix it? Apologies for bad grammar and/or bad formatting.

EDIT: I tested several times and the first cylinder actually isn't working well either. So really none of the three is working now.

I was going to recommend lubricating the pistons, but seeing you already did exactly that, I can only say you should try to isolate the source(s) of the problem.

Since you have at least one working cylinder, the compressor and the feed tubes should be all right. This leaves the following possible points of failure: switches, subsystem hoses, working cylinders. Try disconnecting the hoses from the switches to see if the valves work well, and try connecting the compressor directly to the hoses the valves control to check the individual pneumatic circuits.

If a hose has developed a leak, you can also find it using a long hose (to protect the electronics) that is known to be leakproof and a bowl of water.

If the pistons are proven to be stuck, you can try the steps outlined in this answer.


Tufts MAZE LabView Program Will Not Run on EV3 Through the 2012 LabVIEW for LEGO software package, I found an example of a maze from Tufts.  I cannot get it to run on an EV3.  It appears to just constantly execute the initialization.

How can I attach the vi to a question?

LEGO MINDSTORMS EV3 was not releases until 2013, so I think it is safe to say that the software in question was designed for the NXT only and will not run on the EV3.


Which set includes a large white mask I bought a sealed bag at Goodwill but It did not include any information on what set it is from.

Pieces look like large white body plates, skeletal/Stormtrooper mask and tusks.

The mask in the first picture is from the Hero Factory set Witch Doctor.
The other pic looks like it's from the same set.


Do WHITE LEGO elements fade or yellow while sealed for years, or do they stay their perfect white original color? I was wondering if anyone has opened a sealed set like Taj Mahal or Star Wars UCS Imperial Shuttle after it had been sealed for years, and if so, were the white LEGO elements still perfectly white, or did they fade or yellow even while sealed? I'm debating about buying an expensive UCS Imperial Shuttle that's still sealed, instead of Bricklinking, just so I can have one looking brand new, but wanted to know if it might already have faded or yellowed even while sealed.

Should be Fine
The sealing process, at least in the new bags without perforation, keeps the bricks safe from aging. The Taj Mahal should be just fine, and even opened, my Imperial Shuttle bricks are great!
In fact, all the newer bricks, 2003-2007, seem to be pretty yellow-proof. You'll typically only find those in much older sets.
Yellowing occurs because of UV interaction with the bricks. Box, indoors, away from windows, any of the above should keep them plenty safe.


How can I find LEGO bargains on eBay? Sometimes I have been able to find some good deals on used LEGO sets, however most of the time I spend looking for sets is trial and error.

I usually search from Toys & Games > Construction Toys & Kits > Lego to weed out most of the clone brands and sort by Best Match.

Are there any particular good search terms, web services or techniques that can make it easier to find LEGO bargains on eBay?

I don't think there is a single strategy that will always work - it all depends on what other people are looking for at the same time as you are looking. For example, I have seen Lego Maersk train sets (I'm a Train fan :) ) sell for $250 in certain auctions, but have managed to pick up one with extra power functions for less than that in a separate auction.

Here are a few things that might make your life easier:

Create searches and save them (you can even get notification emails for new finds this way). These are called "Followed Searches".
Use the tips and techniques in the Advanced Search section of eBay Help to refine your searches. For example, if you want LEGO but not Duplo, you could search for "Lego -Duplo".
Always compare with current retail values (check Amazon.com, shop.lego.com or brickset.com) if the set is still current
For sets that are no longer current - look at brickset.com to see what they used to go for. If you have the time, check out Bricklink.com and see how much the same set costs there, or, if you really have the time, use the Inventory feature and see if you can get a better deal just buying the set pieces :). For the popular holiday train (10173) for example, which easily sells for >$500 on eBay, the cost in pieces is typically around $200 on Bricklink, lower if you already have some of the critical pieces.
When it gets to bidding, look into using Sniping software, which allows you to place a bid in the closing seconds of an auction. This often helps you win auctions if no others are using snipes. JBidWatcher is a good starting point.
For bidding, check out what others have already bid ("Bid History") and also look at "Show Automatic Bids". This allows you to see who is really eager to get it and how often they have bid.

There are for sure other techniques out there, but these are the ones I find work best for me.


Creating ski gondolas/tramway with Duplos I've got a three year old who just came home from a ski vacation where he was enamored with the gondolas (like below).

I want to make one with Duplos for him. I'm most of the way there, but have a few specific issues.  He has a 21 month old brother, so I can't use regular legos (or I think this would be easier).

I have the cab from this set:

I plan to attach it to the bottom of a regular wheel base (like the wheel base from the same set), which creates the gondola - all good so far.  However, I haven't figured out how to recreate the track/wires/etc. without some permanent modifications.

I have a pretty large supply of Duplos to work with (including the large powered train set), and I live in an area with a large Lego Store and a Legoland, so I probably have access to anything that is produced and sold in the US, and I don't mind buying odd sets - I just haven't found something that seems like it would work.  I have plenty of duplos to build a little mountain with, and the little guy has sufficient imagination that he won't require a specific color scheme or a skier minifig (which I also haven't found).

I have considered using track, but I don't think I quite have the space for that (as it would take up a lot more) - and would rather do something that appears more like string/wires, as he's very aware of how that works and is very bright and detail oriented.

Specifically size-wise, I plan to build a mountain around 10-20 dots square, and about 8-12 bricks high (this depends in part on how many bricks I decide to use, and on how high it needs to be to make the gondolas work).  I would put the gondola 'base' a bit away from the mountain, and the gondola end point near the top of the mountain.  Sort of like how Playmobil did theirs:

except with a nice large Duplo mountain and a less complex base (I probably would just do a 8x4 platform or whatever size was necessary to manage the setup.)

In particular, I'm looking for suggestions for how to manage the hanging aspect.  Since it's on a wheel base, I can put that wheel base on top of strings or wires or something else, but I don't know how to do that within the Duplo setup; I can make large knots or something through small openings in various piece combinations, and use regular string, but I'm not sure I could do that in such a way that the wheels would stay on (These are regular wheel base wheels, so they don't have anything that would help them stay on the wire/string).

What I have done so far: used a ribbon like suggested, but more of a clothes ribbon. It works well - the fabric fits in the spot behind the wheels and friction is usually enough to prevent it falling back. I have yet to add the winch (not sure it will be  long enough but will see when I get it next weekend). I used a simple stack of squares to anchor it - on the bottom needed a bit more support for some reason but nothing fancy.

(The buildings were child made, by the way :)


Is there a drop-in replacement for 4275 + 4276 hinge? Both parts are not in production since 2008.

Hinges in my sets are in various conditions, some of them are way too loose to my liking. No ones fault, I was active kid who built a lot. But now it's like 10 years too late to replace them with new ones. Or is it? I'd prefer original Lego brand replacement that can be used without changing anything else in building instructions, but other ways to replace them are welcome, too. Restoring the ones I have is another question (that probably was already asked).

Not exactly drop in replacements, this particular modified plate has no protrusions around the hinge, it's entirely flat.

I see two possible replacements:

44301 and 44302. However they "click" in angles of 22.5 degrees and have protrusions...

60478 in combination with 63868 (clip and bar connection) is freely rotating but ofcourse again protrusions...


What can I use to glue LEGO bricks to Metal? So I have no roof lining in my car and instead of replacing it with another carpet I thought covering it in Lego would look pretty cool

What would be the best way to glue the LEGO to the metal of my roof?

I've got a hot glue gun but not to sure it'll work.

This sounds like a job for "Amazing Goop."  It's available at Home Depot and other big stores, at least in the US.  There are a few varieties, including one for automotive use.  It pretty much sticks anything to anything, and once cured, it's on for good.  I've used it for gluing LEGO pieces onto a curved metal surface, and was very happy with the results.  It's a little tricky to work with because it's such sticky stuff, but once you get the hang of it, it's not too bad.  What's great about it is you have a fairly long working time to get the glue on your pieces and get them into place before it dries out. Also it is very strong, and stays flexible, which will be essential to hold up to the vibrations of a car.  One trick will be holding things in place while the glue cures.  Maybe try doing small sections at a time, and using tape to hold the pieces in place.  Also consider gluing pieces onto baseplates, and then gluing the baseplates to your car roof.  It has a strong odor, not terribly unpleasant, but you might not want to drive your car for a few days after gluing.  Good luck!


Does there exist software to test the strength of a designed LEGO model? I would like to build furniture (chair, table,...) out of LEGO blocks.
For this purpose it would be good to be able to test the amount of force a certain LEGO design is able to withstand. I would like to actually use this furniture.

Does anybody know of models or software I could use?
Are there people who tried this before and could give me some pointers?

So far I found some articles about different LEGO bonds and a few on combining LEGO techniques to increase the strength of the structure.

First step, have you read my paper? This should give you a good guide on what is the maximum force needed to break Lego.

With these limits in mind, the next thing to note is that breaking doesn't equal bending. Lego will bend quite a lot before breaking so designing structures that a rigid will basically meet most requirements.

The best book to read is Sariel's Technic Builders Guide. This outlines a number of design patterns that maximize strength.

In general, you should think of Lego as weak steel. Triangles everywhere and vertical plates.


Can you build accurate models using 100% LEGO elements by following Megablocks instructions? I shudder when I find errant MegaBloks in my LEGO elements, but admit to admiring certain in-the-box models offered by them. I know the pictures depicted on the MB boxes are not actually photos of a completed MB model. They are computer enhanced images of what an ideal model would look like if MB pieces actually fit together correctly. Is there a link with images of any 100% LEGO element models built using MB instructions? If there isn't a link, can someone please post an example?

Not necessarily.

It really depends on what you mean by "accurate."  Most (probably 90% or more) of Mega Bloks elements have identical, or at least functionally identical, LEGO elements.  However, there are a number of Mega Bloks elements that you can only approximate with LEGO elements.  For example, Mega Bloks hinges rotate around the center of mass through 100+ degrees center at the vertical, whereas LEGO hinges rotate through 90 degrees from horizontal to vertical.  Also, Mega Bloks has a SNOT piece with studs on both sides that LEGO unfortunately does not have.

If you are willing to slightly modify the instructions and accept a slightly different model, then yeah, you can reproduce anything made by Mega Bloks using LEGO elements.  But if you want the models to be 100% accurate, then no, not all Mega Bloks sets can thusly be reproduced.


Why do LEGO boxes have a maximum age limit? I am wondering why do LEGO boxes have a maximum age limit printed on them?

My girlfriend has just gifted me LEGO Starfighter (8088) and it has an age range of 8-14. Why not just write 8+? Are there any technical objective reasons?

I believe it shows the target age range of the model - perhaps kids who've been doing all the harder Technic or more complex models - for example the VW Camper Van is rated 16+ - and might find it a bit "simplistic".

Other examples include The Super Star Destroyer, also at 16+, the Tantive IV and Republic Drop Ship at 14+, and the Death Star and others at 12+:


Creating arrow patterns What methods are there to creating  convincing looking arrow patterns on walls and floors? (Without stickers or printed pieces)
My current solution is to use "relief" building with slope pieces, which looks pretty good but aren't flat:

This is using the headlight piece, which allows many interesting possibilities:

I'm also aware of various solutions using the tiny slopes, such as this sideways construction for chevrons used on the Horizion Express:

There's also sloped striping using 1 plate offset that have a tiny gap and I'm not sure if they can create proper arrow patterns (the head of the arrow should be triangular and not wedge shaped).

Looking through slope pieces, I found 3044c which allows this small 2x2 arrow:

Another convenient way I found is with the new triangular 2x2 tiles. The only issue is that the color selection is a little limited. For simple pentagon shape, Modified 2 x 3 Pentagonal Tile is quite versatile.


Lego Mindstorms RCX RIS 2.0 IR tower Windows 7 / XP driver So I've recently dug up my old Lego Mindstorms RIS 2.0 (RCX) and have spent the past few days trying to install it into my Windows 7 laptop. It worked fine, except it could not find the correct drivers for the IR tower. Installing it on a Windows XP Virtual machine has given the same result.

Any suggestions/patches?

I have the RCX IR tower setup and working on my Windows 7 laptop.
I downloaded the drivers from the ROBOTC.net site here (labeled 'RCX Device driver')

Direct file download link

Note: I am running Windows 7 32-bit, according to the ROBOTC site, this driver is 32.bit only and

  No known 64-bit driver is available for the RCX.


How has the basic brick changed over the years? The basic 2x4 brick has many versions. For example the modern one has thinner walls and funny shaped tubes  compared to an early 1980s brick. What were the changes over the years and how did they affect building?

I can't provide a list of all the minor changes, but I can at least tell the most significant change made in the history of the basic 2x4 brick (which applies to all other bricks and parts, too):

1963: Material changed from Cellulose Acetate to Acrylonitrile Butadiene Styrene (ABS)*

In general, there are no essential changes made: a brand-new brick still fits together with one from before 1963 as long as the Cellulose Acetate hasn't deformed too much during ageing (which is the main reason they switched to ABS, it's more robust, scratch-proof and doesn't deform so easily).

The main "change" that really affects building is the continuously improving precision in production - this happens all the time, so there's no point on the timeline. The effect is simple: better fitting bricks improve the stability of your construction.

*Transparent bricks consist of Polycarbonate, axles consist of Polyamide