text:
How can I automate orders from Lego Pick-a-Brick?
Is there a way to automate the process of ordering from Lego's online Pick-a-Brick?  I'd like to be able to go from a .csv with part IDs to a filled cart on their site, or even all the way through to a placed order.  Are there any options short of using a web testing/automation framework to drive the site?

Considering LEGO tends to change the design of their web pages from time to time, I'm sure even a web automation will prove difficult, but I don't see any other way.

I believe that many AFOL user groups had previously been able to buy in bulk from LEGO, but I don't know if that's still an option with the release of pick-a-brick - however as Joubarc points out there are often limits on the number of different elements, as well as a group limit on the number of bricks. Couple that with the fact that the process often takes months to deliver, and it's not an easy option.
Another option would be to take it offline: the LEGO catalogue often lists Pick-a-Brick elements and has a postal order form, so you could format that up in your spreadsheet application of choice and mail it in.
Doing a quick snoop around the network traffic when adding items from Pick-a-Brick shows that currently it uses a fairly simple post to submit the details to the basket:
ba     0
bricks 4239601,1          <- ElementId,quantity
cat    UK
id     4239601,1          <- ElementId,quantity
sid    0.4886243118128015

So something could possibly be created, but as Joubarc points out, there's no guarantee that the site would continue this way.

Cubs do indeed have this option, but there are conditions which limit its usage. In particular, there may be a limit in terms of number of different elements, so if you have to compromise between all members of the club to select the elements you'll order, it means most of the time you may not be able to get exactly what you want. And of course, while the club may be able to send a csv file (I'm not even sure about that), they'll have their own internal process to deal with. Ha, and it takes months, too, so it's a very diffrent route from the PaB.

+1 for the postal form idea; I hadn't even thought of that.  Another limitation with the BulkLUG route is the restriction that you aren't to resell the parts.


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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?

I owned some old 1x2 light bricks. The light part fit into Technic holes. I didn't notice any heat issues with them.

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.

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Has anyone automated the LEGO hand sorting process beyond "pawing & piling"?
I need to rephrase my question. Has anyone built or used a large pigeon hole/ chute/ bin collection system to sort LEGO elements? The sorting system doesn't need to be made of LEGO bricks. I just want to know if any of you studio builders sort your elements in a more organised fashion than the average fan. I'm trying to figure out if this is a project I should take on, or a boondoggle I should avoid...

I'm imagining a sorting table with a slotted back panel into which you drop the pieces and retrieve them from a series of collection trays. It's still sorting by hand, but it would accelerate the unbuild/sorting process. It would be great to see if anybody has done this.

https://bricks.stackexchange.com/questions/6064/quick-way-to-inventory-parts has an answer with a sorting machine build from bricks, NXT and a computer.

While they won't do the sorting for you like that clever youtube video, there are a couple of commercial sorting products that can help you bulk-group your legos by size as a preliminary sorting mechanism, through differently-sized grates.
Box4Blox has been around for a while. Good review of it at Brother's Brick.

Lego has recently produced their own similar Sort and Store shaped like a minifig head:

At our house we organize by color, and have a large bucket of each (mostly because its easier for the kids to help maintain the organization, hypothetically anyway...). I've toyed with the idea of getting one of these, pouring each color bucket through, and ending up with convenient size-groupings within each color. Should be much easier to find what we need.

Thanks. We're getting closer. The obsessive compulsive side of me says I should build one. Rube Goldbrick, here I come.

@MajorStackings: Perhaps a "vibrating table"-style mechanism starting with sorting screens like this?

I was leaning towards a hand sorting device. I had a differnet concept in mind, but this is a great answer. Thanks.

I see a lot of people sort Lego by color, and I don't understand it at all.  If you have your blocks sorted by shape, it's very easy to pick out the right color (assuming you're not colorblind).  If you have the blocks sorted by color, it's going to take a lot of looking to spot the right shape in there.

I have a fairly large collection.  Processing bricks is a lot more pleasant with my homemade device, which is vaguely similar to the devices above, but made from MDF.
Note that the commercial products have holes that are square, not round, so the size of bricks that is blocked by them is kind of variable.  My sorter has two sorting levels, one with 30mm holes and one with 15mm holes.  Because LEGO bricks are 8mm per stud, nothing 4x4 or over falls through the top level, and nothing 2x2 or over goes through the second.  I could have done 22/23mm holes for 3x3s and 7mm for sub 1x1s, but empirically they're rare pieces and not worth the effort. The holes are laid out in a hexagonal grid, on a sheet of MDF large enough to cover - and fall straight through into - my storage boxes (450mm square, as that's the size the sheets come in).  Spacing of the holes and thickness of the MDF was selected to ensure strength - MDF doesn't distort too much before breaking, and using MDF was important because it's cheap, common and unlikely to damage the bricks.  There are sides to each tray to prevent spillage, and nodes on the underside to lock each layer into the one below.
The hardest part in constructing my sorting trays was finding drill bits for making 30mm and 15mm holes; I found only one 30mm spade bit in my local hardware superstore, and I had to go to a commercial tool supplier for the 15mm bit.  I also needed a new drill, as my existing one couldn't spin slowly enough to make round holes with a spade bit.
So, here's the entire unit; you can see the sides to hold a reasonable amount of LEGO without spilling over:

And here's what LEGO swamping the 30mm holes in the top looks like. Most of the time I'm operating at this level; the second level can contain a large number of pieces given they're so much smaller.

The second level gets the smaller parts falling through while you're pawing through the top tier.  You can see the spacing created by the tall corner posts, this is to allow a 2x16 plate (the longest part I'd expect to process - 128mm) to fall through if it wants too - but typically something that long won't fall from the top level, as its lowest centre of gravity lays it flat and so the great length won't fit through the topmost holes.  If one were to slip into a hole, it could be raked into a position to fall, so about 10% or 20% of pieces as large as this fall through to this level.

The small detritus finds its way to the bottom level

Here you can see the locking nodes that prevent the tiers rotating and moving off the tier below.

Prior to building this I experimented with a number of designs and found that they had a common problem of clogging up.  This experiences that to some extent too, but has a vast number of holes to minimize the impact, and a finger poked up from below can clear the blockage.  Radar dishes and large cones, for example, are good at filling holes.
I do have a tumbler to separate out plates and other small items from bricks, but it requires a lot of work to cause the separation so I wouldn't recommend it as a sorting tool.  I could supply an image for those with an academic interest.
I showed my device at my local LUG, and a year or so later another member went and made his own tennis-racket inspired LEGO sifter. I humbly suggest this device suffers from the same problem with square (or sometimes triangular) holes that the commercial devices exhibit.

Thanks for the pics. I bet you've gained a ton of build time by reducing your sort time. I like the size of the footprint of your device as well . It's much smaller than the behemoth I have in mind.

My tennis racquet based one is for sorting mostly Technic, where I have a lot of sub-1x1 parts and very few studded parts, so it works pretty well for that. Rob has it now so it'd be interesting to see how it works with non-Technic.

I designed and built a lego sorting and storage desk for my son late last year. It has 16 bins and 16 corresponding holes in the top. It also has an interior baffle system to keep lego pieces from jumping into incorrect bin. I had to go through several designs to get it to work right, be ergonomic (all drop slots within reach while seated), and make it easy to assemble.
Although I have patent pending on the design, someone with reasonable skills could come up with their own version for personal use.
The table works well, but it is designed for center-of-room use to allow access to all the bins. My son and my wife often sit opposite each other at the desk while sorting to make things go more quickly.
We sort by type mostly, with simple combinations of blocks sorted to one side of the table, and non-block type pieces to the other.

This is brilliant! A compact fordable version would be awesome.  This way you can get it out only when sorting.

Thanks! My wife asked me to build my son a storage system for his Lego collection in late 2014. I spent days searching the internet for an idea like what Major Stackings mentioned in his post here. My wife sent me all sorts of Pinterest ideas, but I knew he wouldn't keep any of those organized because they all involved large containers spread all over the place, or stacked on top of each other. He actually uses this desk as an all-in-one sorting, storage, workspace, and display system.

Here's a video I found, featuring a fully automated LEGO sorter made out of LEGO itself:
https://www.youtube.com/watch?feature=player_embedded&v=6lZ9rSZwDzE
Keep in mind that the time it takes you to build and use one of these is probably greater than the amount of time it takes to sort by hand.
EDIT:
I don't think slots would work great as the bricks could fit into multiple shapes/sizes of holes. One thing you could try is a "panning for gold" method - put pieces in a bowl and swirl them around. The heavier ones should fall out. Don't know how well it would work, but it is worth a shot.

Thanks! It's not quite what I have in mind, but thanks for your help.

@MajorStakings How is this not helpful? The only difference with what you want is the output sorter (shoots instead of buckets)

That's the video I was looking for. I like how this sorts beyond the colour of the brick.

@pcantin: I think the device in the video is awesome, but it seems somewhat limited by the number of elements types it can sort at one time and by the speed it can sort them. I'm picturing a sort by hand "mailslot" pigeon hole system that routes to dozens of trays at once.

@MajorStackings The hard part is not the output mechanism.  Recognizing the bricks is everything and this system is amazing at that (even using computer vision).  Once that's done, optimizing the speed can be done several ways and on several components (software, mechanical, structural).  One simple way to augment the speed would be to put many similar detectors in parallel but connected to the same input and output systems.

The device in the video is fantastic but is that a UV light it uses to illuminate the bricks for identification? Nooooo! The enemy of the blue/white/light grey brick! But just don't sort your bricks too often and it should be ok :-)

Yes. Jacques Mattheij made a pretty awesome machine using some feeders, machine learning, and air blowers to sort out the top 1000 parts by popularity. It looks like he's well on his way to sorting two metric tons of bulk LEGO: https://jacquesmattheij.com/sorting-two-metric-tons-of-lego
More discussion on Hacker News, including a bunch of comments by Jacques under the handle jacquesm: https://news.ycombinator.com/item?id=14226889

The most promising approach that I have seen is being used by LETZGO (http://www.letzgo.co.kr/home) a Korean start-up that aims to make Lego affordable by offering Lego sets on a rental basis.  Naturally the rental process makes sets liable to lose/damage pieces and so they appear to have developed an automated process for sorting and to verify the integrity of sets.
There is footage of the system in action here: https://www.youtube.com/watch?v=1WD1sM-b2Qc
It appears to weigh pieces in addition to using various computer vision processes to effectively identify pieces individually.
It sounds like they may be considering open-sourcing some of this system (https://www.youtube.com/watch?v=Ck7IOx2Pp3c).  Show your appreciation and share some love with the creators!  (and cross your fingers they are willing to share their work!)
An automated Lego sorting system developed by the global Lego community would truly transform the hobby of Lego!

If you happen to know more about this project please leave a comment :-)  If you speak Korean you should find out more!

We have a small business sorting LEGO for customers (www.brick-sort.com)... and we've tried many different machines. Bottom line is that, unless you're dealing in tens of thousands of parts, Pubby is right: "...the time it takes you to build and use one of these is probably greater than the amount of time it takes to sort by hand." I think people forget about the "using" part of this. Someone has to stand there and shake the basket. Someone also has to break-apart the bricks. I find that our minimum wage labor does the job much faster.
When sorting by color, yes, it helps to have a table with a big hole in the center where you can toss the bricks (a bucket underneath catches them). The problem with collection trays affixed to the side of the table is that they fill-up quickly.

I've considered building a pigeon hole sorting station inside a stepvan. I'm not sure if it would ever pay for itself though.

You and I arrived at similar solutions.  I used plastic buckets to sort by size:
http://www.instructables.com/id/Lego-Brick-Sorter/

Hi David, and welcome to LEGO Answers. We're looking for long answers that provide some explanation and context - and not just links to another site - if you could include a copy of your key image that would help immensely (i.e. step 2). Thanks :)

adding images is a great way to make an answer come to life :)

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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?

The first step would be to find a some MegaBloks instructions, unless you're possibly looking for someone who's already done this?

The wording is confusing me. You want images of Megablok models built using LEGO bricks?

@Peter: Yep. Somebody must have done it. It is kind of tempting.

@Pubby: Yes. I'd like to see examples of LEGO models constructed with Megablok instructions.

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.

Yep, you can just see a number of elements in the photo in my compatibility answer (http://bricks.stackexchange.com/a/754/56) that I don't believe have a direct LEGO counterpart, from the hollow "frying pan" that Harry's holding, the 1x1 angular SNOT brick (the LEGO one is much thinner, and doesn't have a stud on both sides, but a hole on top), the rounded double lights and even the sloped brick they are attached to. I'll try and dig the model out and see if I can photo all the different bits.

You could conceivably do it, but the flat Megablock bricks are thicker than Legos, so the Lego creation may seem long and flat.

Yes - I remember as a child, I built the USS Kittyhawk (a set that is an absolute nightmare to build with Mega Bloks) out of LEGO parts. All of the pieces, aside from the stickers, have either an exact or pretty close LEGO equivalent. You will also need to do the deck with plates instead of the large MegaBlok plates, but this allows for much more detail and a more realistic looking carrier deck.
http://www.amazon.com/MEGA-BLOKS-PROBUILDER-USS-KITTYHAWK/dp/B00004TRZY
Unfortunately, it was so long ago that I can't find any pictures of what I built. I do remember that you need a lot of gray bricks. I would recommend this set above all the other MegaBlok sets for replication in LEGO, as its a massive build and especially fun when built with pieces that actually stick together. And its a lot more fun to plan out all the LEGO pieces you need and salvage them from the Internet than to get them all in neat little bags.


text:
How much does a life sized LEGO person sculpture weigh?
Generally, how many pounds of LEGO would it take to make a life sized person sculpture?
Do they weigh anywhere near the same as the real person they are modeled after?

The image posted in your question shows the Lego brick artist Nathan Sawaya.
On his website, he states:

A life-size human form sculpture typically has 15,000-25,000 bricks.

So, lets use 20,000 for our calculations.
Next, how much does a brick weigh, well of course it depends on the type of brick, but if we take the common 2 x 4 Brick , Bricklink tells us that one 2 x 4 Brick weighs 2.32g.
20,000 x 2.32 = 46,400g
= 46.4Kg
= 102.3Lb
= 7.3 Stone

So one could say they are very roughly equivalent in weight.
But if anything, the Lego versions are likely lighter than their human twins. This is especially true if we consider that many of the bricks will be smaller than the 2 x 4 Brick we used in the rough calculation above. For example, according to Bricklink, the 2 x 3 Brick weighs 1.92g and the 2 x 2 Brick weighs 1.21g.

Hmm, two 2x2's would weigh more than one 2x4 (2.42g) - generally the density of the element would increases as the size decreases because more of the volume is taken up by the thicker sidewalls.


text:
Is there a way to build a stronger LEGO ball than what was done by the Mythbusters?
In one episode, the Mythbusters busted a fake video by building a 7' tall LEGO ball.  The construction did not roll very far before falling apart.

Assuming that they only used standard bricks (with studs on top only), is there a better build pattern to make a stronger ball?
Extra info: They explain their build method in this video.

Replacing bricks by plates could also strengthen the structure

I wish I had 500,000 bricks to test some theories

I thought they could have done it stronger if they'd had more time too.  It would be awesome if the great LEGO minds here came up with more things for the Mythbusters to test with LEGO bricks.

There is a problem with the Mythbusters building technique.
One of the first things you learn about building with Lego is that, if you want a stable structure, your bricks need to interlock as much as possible.
The Unofficial Lego Builder's Guide illustrates this rather well:

Unfortunately, to make the build easier the Mythbustes team assembled a series of large blocks and then assembled these meta-blocks into a ball. The problem with this approach is that it creates lines of weakness between the meta-blocks.
In the shots of the ball falling apart you can clealy see these sub-assemblies inside the ball, which suggests that it did indeed break up along the lines of weakness between them.
For maximum strength, the Mythbusters team should have built the ball in layers of single bricks, ensuring that in each layers bricks bound the layer below together as much as possible.
All that said, I don't think that the faulty building technique really invaidates the Mythbusters conclusions. There is simply no way that a Lego ball of that size would remain intact. You would expect, for example, that the outermost bricks would fall away in exactly the way they did in the Mythbusters. And in fairness, building the ball with fully interlocking bricks would have taken considerably longer than doing so the way they did.
Of course, if they're willing to supply the bricks, I'm sure we could try to do it better for them!

Totally, building meta-bricks and then building the ball out of them is a sure way to introduce many weaknesses. Single layers of bricks arranged in a way as random as possible should be better.

absolutely right. i don't buy that experiment of theirs for 1 second.

You could probably make it stronger with some of the bricks that are 2-4 bricks tall. That would give it more rigidity.

You could use lego technic and that would make the ball really strong, or you could cheat and glue it together! the other idea i would have would be to make the ball as curved on the surface as possible that way when the ball rolls, less stress is inacted upon on single point on the surface- which lead to the breakage on film and cracked it wide open! so not only a slightly different method used but also a different shape could used to make the ball more ball shaped other than a blocky version- the lego theme parks have many examples of near perfect curved surfaces so this could be done- with a few extra different shaped pieces and not just the ordinary building blocks as seen on the programme.
Also as a general point but i didn't see anyone on the programme that could call themselves an experienced lego builder?...unlike james may did in his version.


text:
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:


text:
How to repair leaky pneumatics?
Some of my pneumatics parts, mostly pistons, have seals which no longer prevent the air from escaping completely. On some parts they are unreliable and on others they are not working at all.
Why do those parts become leaky, how can I minimize the risk of it happening with maintenance and/or proper storage, and is there any way to repair already leaky parts?

Zhaph suggested disassembling the piston and replacing the seal with an o-ring, however the seal in question was not a simple o-ring and getting a replacement is properly difficult:

From the left:

Top piece locking everything together
Top rubber seal, with a bit particular shape
Bottom rubber seal, which is just a wide rubber ring
A plastic spacer between the two rubber seals

While the top piece appears to be safe to remove, the bottom rubber seal easily gets damaged when you try to force it off the piston. The amount of pressure it could retain after forcing if off a couple a times became limited.

I hadn't realized what the going rate for pneumatics was on bricklink.

Until recently no sets containing pneumatics had been produced for years, so they had become rather rare while still having demand. I thought it would have improved by now, but I guess stock is still low...

The parts become leaky due to the seals inside the pistons deteriorating.
Typically, the seal is made with an "o-ring" - a circular rubber band (cross section as well as the shape) - if this is the case in the LEGO pistons, and then it's possible the o-rings are made with similar rubber to the LEGO rubber bands, and then they will deteriorate over time in the same way the rubber bands do.
I've not tried dismantling any of my pistons, so I couldn't say how easy they are to repair - they look like you should be able to unclip the black part and access the piston that way (there's a YouTube clip of someone doing so here, you can just see the piston head too, but I can't confirm the o-ring).
A good car spares or similar type of shop should be able to sell a selection of replacements.
From my time spent diving, there's not much you can do to stop this happening over time, other than keeping an eye on them and checking them regularly for replacement.

I have tried disassembling one and there are three rings. In the bottom of the piston is a fairly wide ring made of rubber. Then comes a small spacer of ordinary plastic. At the top there is a fairly complex part made of rubber and sadly this is the one which is normally causing trouble. Getting a replacement for this one will be difficult... I will add a photo in the question.


text:
How to make custom LEGO signs, newspapers, etc.
I have several ideas, but I am finding it hard to get started. What I am interested in is making my own decals for signs, newspapers, artwork for the walls and others. So far I haven't had any luck.  Is there a site that has LEGO clip art backgrounds, lettering, etc.?

BrickLink has a huge collection of sticker sheets which can be used for inspiration. My answer from a previous question explains how you can obtain decals from existing sticker sheets.

Your question is vague. Are you having difficulty with inspiration, artwork, printing or something else? What do you want "LEGO clipart backgrounds" for, and what do you think they are?

Well I don't exactly know what you mean buy a sign like one that he/her can hold or a sign in the ground? Moving onto the newspaper you can get white sticky clay and get two white 6x5 pieces or a size you like and fill in the crack in the middle then put one piece of clay in the Lego persons hand and shape it in a Lego rectangle size
 Hope this helped


text:
Is it possible to power supply an EV3 hub through the battery slot with 10 V?
I have two USB power banks that according to USB standard supply 5 V. I want to power my EV3 brick using my two USB power banks wired in series and to the EV3 battery slot.
Can I power supply an EV3 hub through the battery slot with 10 V?

Don't ever put power-banks in series or paralel !!! They are not plain batteries.
Unless you are an electrical engineer that understands the exact circuitry inside the power-banks this is in general NOT safe.
Wiring multiple power-banks together can lead to serious problems. Like premature wear on the power-banks or even damaging them completely (as in "overheating until they catch fire").
And, in this case you don't need to as David already said in his answer. One should suffice.

Yes. The EV3 technically only needs 5V to run. And just the EV3 by itself pulls around 200mA at that voltage. However, motors could be a problem. They can pull up to 1A when stalled, which could overload the power supply. Without knowing the technical specifications of the actual power supply, it is hard to say what it is actually capable of.

Aren't there some typical values for power banks? Even the cheapest ones seem to be able to deliver at least 2.5 A.

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text:
Identification of this set with red, white, and blue bricks (mostly)
Consider:

What set do these pieces go to? There is a minifigure that looks like it might be space-related.

This appears to be 60079-1 Training Jet Transporter.

I found this by searching for 6096487: BRICK 4 X 6 W/BOW, INVERTED and looking at sets that included this part and some of the other parts visible in the bag.

Thank you so much!

No problem. If this is a correct answer, you can thank me by upvoting and accepting the answer.


text:
Finding the angle for an isosceles triangle roof
I am using clips to make a roof shaped like an isosceles triangle.
This feels like one of those things that would be trivial with physical LEGO bricks, but it is near impossible with Stud.io.
How can I calculate the angle that the roof needs to be at for the clip to hold the bar piece?

You are trying to assemble a triangle with inclined parts of 8 units in length and horizontal line is 7 units. The rest is math:
∠α = cos⁻¹(3,5÷8) = 64.0555°
Due to slight imperfection in LEGO assembly you can easily take a value of 64° for one side and 296° (you were close!) for another.
I did a mock-up in LDCad and proved that it works with angle of 64°, as you can clearly see below:

To get the exact answer, this is what high school geometry and trig is useful for in the real world :)
Alternatively, switch off collision detection and just try changing the angles in small increments (e.g. 1 degree) until it looks right. Type the angle into the box shown in the picture, don't try to rotate the parts with the mouse.
Then switch collision detection on again to check if you were close enough.


text:
Is the Antikhythera clock design available as Open Source?
After reading and watch the video about the Antikhythera Clock, I am curious if the design reference (or better yet the instruction manual) is available as OpenSource.
Why? Because it would be cool to have one of this sitting on top of my desk.

This may sound patronizing, but did you try to contact the designer himself? There are contact informations at the bottom of his page (while you're at it, ask him to come post his answer here :-))

Why? Because it would be cool good enough for me.

If you could not get it, then you might try Hans Andersson's clock :)
http://tiltedtwister.com/timetwister.html
And here's the instructions manual:
http://tiltedtwister.com/tmtwdownload.html


text:
How do I know when current sets will retire?
As the title asks, how is the easiest way to find when current sets on the Lego website will be retired and no longer sold.
For example, the 10197 Fire Brigade has been around since 2009, same as 10193 but both are still selling.  While Ninjago is currently changing and set 2258 suddenly is no longer for sale in the Lego Store at Disneyland and not available online.  Yet that series only came out this year.
So how can I find out when sets are retiring.
(side question: why does lego.com drop items off my wish list without notifying me)

I think the bigger question is why does shop.lego.com remove products from it's index instead of just saying they are not sold anymore. Links at say, technic.lego.com will link to products on shop.lego.com that are not there anymore.

See also the related question: How long are Star Wars exclusives usually in stock for?

The LEGO Shop online website has a page where you can see which sets are marked as 'Retiring Soon'.
 USA - LEGO Shop
 UK - LEGO Shop

I'll take a stab at starting to answer this one, but I'm pretty sure it's going to need some refinement as it goes along since the answer does not appear to be quite consistent across all themes.
In general you can assume that a particular set will only be available for one year after it has been introduced.
The exceptions to that general rule seem to be:

Basic brick sets seem to stay mostly the same from year to year, though occasionally there is a tweak to the price or part assortment for whatever internal reason.
Sets over US$100 appear to stay in production for around two years.

You can find out when a set went into production by checking Peeron, Bricklink, BrickSet, or any number of similar fan databases.


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PC To NXT Brick via Bluetooth
We have a fully working java program that can connect to another computer and can send messages from this (both sides run java and we used SPP Server and Client).
However, when trying to connect to the NXT Brick and send a message via Bluetooth, we are able to pair with the brick and send a message but we have no idea if the NXT receives it.
When we tried to use Java SPPClient on the computer(we provide the ServerURL of NXT to java program) to send the message to NXT Brick running the RobotC, it doesn't work. On the java side, this error is given:

Failed to connect; [10064] A socket operation failed because the destination host was down.

Using RobotC the brick is waiting for a message to be sent and it is awaiting 3 integers to help the robot move.

that sounds like a firewall problem. Is the java program trying to access the internet?

@tuskiomi The socket connection error is for the bluetooth connection, not the internet. The firewall should not interfere in local bluetooth connections.

Have you updated the firmware? That may be a problem but it also may be that there is an error connecting using Bluetooth. “Destination host was down” means that the coding platform could not connect to the NXT.

I have a strong suspicion that your COM3 is connected to BlueTooth so your Python program can't connect.
I would go through the information in the NXT Bluetooth Developer Kit (available from the LEGO MINDSTORMS download page) to troubleshoot the process.
Beyond that, this sounds like a potential general BlueTooth issue, and not directly related to the NXT brick.
In the worst case, there might be a hardware issue with the brick itself. Lending another NXT brick and checking if it gives a different result should answer that question.


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How can I wire up the LEGO 2838?
I would like to know how to hook up the LEGO 2838 9v motor. I understand that the Power Functions extension wire is compatible with the 9v system, but how on earth do I wire them up?

To wire 2838 motor, you have to use one PF extension cable, one end connected to PF power source (either battery box or IR receiver), the other end has a 9V compatible plug on bottom. Unfortunately, 2838 also has its connector on bottom, so you also need a 9V cable (such as this one) to connect them.

You could also use an extension plate (2x4 or 2x8) underneath the motor, so that you can plug the PF extension cable on it.


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Buying Individual MiniFigures
I was big into LEGO bricks when I was a kid (now 33), and now my son is getting into them. I'm a huge collector of things (not a hoarder, a collector), and, like father, like son, he wants to collect the minifigures, past or current.
I assume eBay is a great place for these but the prices probably tend to rather high.
Then while searching, I found BrickLink, which seems like a pretty good place to start.
Is this the truly best place to buy them, or are there other places just as good for minifigures?

Yes, BrickLink is by far going to be your best bet if you are looking for specific minifigures. Make sure you create a wanted list with all the minifigs you want, then quire by shop to see which seller(s) have all or most of the minifigures you want. You can save significantly this way on shipping.
eBay is not so good for individual minifigures as the prices tend to be much higher than on BrickLink, however it is still a great place to shop for bulk minifigs. Deals are not as easy to come by as in the past as people have smartened up and most people know the value of LEGO.
I would suggest to pick a particular theme to collect and be very specific on what you want to get, otherwise minifigure collecting can get out of hand pretty quickly. There are thousands of minifigures (all listed in the BrickLink catalog) - you can get a good selection for reasonable prices ($3-$5 per minifig), but in some themes having minifigs in the $20-$50 range and more is not uncommon (Star Wars is one of them).
Those little people can quickly take over your vallet. So best is to keep them under control for a fun and long-term hobby. ;)

Great suggestions! Yeah I thinking about going with the City theme, since we have an HO scale train set we put up each year and that seems like a good compliment for the train set.

You can go on Firestartoys! They sell individual minifigures from all themes.


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Which wheels are suitable for Power Functions M-Motor
I'm attempting to build a small self-propelled LEGO robot. Initially I was attempting to use some cheap DC hobby motors but I spent a lot of time trying to attach LEGO wheels to the motor's 3mm spindle and could never get enough torque to make the robot move.
I have now purchased two official Lego M-Motors. Unfortunately I don't have any wheels with a large enough diameter so I'm now looking around to get some matching wheels for the motors. The wheels will need to have a diameter of at least 40mm (the motor's height is 24mm).
I have had a look around but am a bit bamboozled by all the options. Has anyone use one of these motors in a robot and have any suggestions for a wheel type?

Sariel has a comprehensive list here: http://wheels.sariel.pl/
Your can also use his gear calculator to determine the output drive parameters (Torque Speed etc).

The M-motor is directly compatible with almost all the wheels that LEGO has produced, and, with a little building, compatible with every wheel imaginable, even brick-built wheels.
If your problem is that the wheel is smaller than the diameter of the M motor, perhaps you want to attach the wheels to an axle, and then drive the axle with the motor.  There are many different gearing solutions variations that would accomplish this.
If you need to purchase one or more wheels, Bricklink is a great site to buy individual bricks.


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Flash update breaks the Mindstoms NXT viewer
After udating to the lastest version of Flash on my Macbook Pro (OS X 10.7.4) The Mindstorms NXT software that comes in the box no longer displays the build instructions. It does load up, but the build instructions pages are blank.
Is this a known issue, and is there a fix available?

You may want to contact the LEGO customer service about this, even if they don't have a fix ready at least they'll know about the problem.

This is fixed using the NXT software version available from http://www.lego.com/en-us/mindstorms/downloads/software/nxt-software/ instead of CD that came with the NXT set.


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Technic axle corrosion? What happened here?
I got my LEGO from storage from when I was a kid (1980s) and while almost all bricks are in good condition, the Technic axles are in a pretty bad shape. They seem to have corroded(?). Please see the attached picture. This has happened to almost all the axles but with different degrees of severity. None of the other bricks, technic or not, black or not, has suffered this.

Any idea what might have happened and how to prevent this?
EDIT: They were stored in plastic bags sorted by color (one bag per color) inside a larger canvas bag in a non-lit, dry environment (garage). All other bricks seem to be fine, regardless their color. Stickers that had been applied survived very well (bright colors) and still hold strongly. Once I got the collection back I mixed the bricks and ran them under warm tap water and let them dry on a towel on the floor for a day. These were the only bricks that were affected.

That's very sad :( I must say I've not noticed my old ones doing that yet - when you say "storage" what were they stored in, where were they stored and what sort of conditions have they been under?

Take a close look at your Technic bricks from this collection; is there any indication of that kind of "corrosion" on the inside of any of the holes?

It appears from the photo that there may be some "blooming" where the axles have changed color? You say you rinsed them, but I wonder if you noticed whether the axles felt oily or sticky at all beforehand?
This would be consistent with the kind of deterioration that is common with Polyvinyl Chloride (PVC), a kind of plastic that was once common in toy manufacturing. I don't know for certain that these early axles were made from PVC, but I do know that LEGO did formerly use PVC for some non-brick pieces, and I have seen similar deterioration on other PVC items. This is a known problem with Barbie dolls, for example.
PVC typically has a plasticiser added to it to make it flexible, usually dibutyl phthalate. This plasticiser gradually "leaks" out of the plastic, leaving it discolored and vulnerable to deterioration and creating gasses (like hydrogen chloride) that will attack other PVC and hasten the process. Heat and light will accelerate the breakdown, and you indicate that these were stored together in a plastic bag. That might have contributed, as the gasses and plasticiser were trapped in contact with the pieces.
Phthalates are toxic and are now regulated in the US, EU, and many other countries. LEGO no longer uses PVC except in some limited applications like the insulation for electrical wiring. LEGO was one of the first companies to begin phasing out the use of PVC, in the 1990s.
To slow the deterioration of PVC, keeping it away from heat and light will help, as will keeping it ventilated to remove the harmful gasses produced by the plasticiser.

That would not happen naturally. I have Technic (actually, Expert Builder, to give you an idea of how old they are) axles that are probably 25-30 years old and look like they were purchased yesterday. At times they have been stored in a hot, humid attic in New York City, reaching temperatures over 120 degrees F.
What maybe happened here is some oil or other non-plastic-safe lubricant was applied to the axle in whatever model it had been made into, and perhaps cleaned off but not entirely, and over time, the lubricant destroyed the plastic.

Technic axles aren't known to naturally deteriorate as described. The most probable cause for corrosion would be influenced by the way it's been stored. The bricks may have been subjected to a powerful chemical (perhaps used for cleaning?).

They were stored in the same conditions as the other bricks and were washed together with the rest of my collection. (more details on this edited into the question)

Where do you live and how the bricks were stored?
I see 2 hypothesises.

Chemicals affecting the axle plastic. If they are made of a different recipe than the usual ABS, it could explain why only them were affected.
On high enough temperature (in a car, on a summer sunny day would be
enough to affect lego bricks).  If the bricks were exposed to light.
it could explain why black axle were affected? Maybe they are small
enough to warp while other bricks aren't. I would check if the other
brick still fit, you might be in for some surprise?

Let us know..

Well here I would tend to say that axles are not ABS, which may explain why they are affected  differently. Not sure what material they are, though, or how to prevent this.

Ah, yes I remember reading another recipe is used for flexible pieces such as axles.

What is amusing is that this was written by you :).

I would dismiss #2. They were stored for +-15 years in plastic bags with other bricks (sorted by color) in a garage. I don't know about #1 if the plastic bags themselves could carry these chemicals (what would they be?)...

Do you remember having put oil or other kind of lubricant on the axes when you were a child?
The "corrosion" seems to be in very localized  parts of the axes, and oil can penetrate plastic easily (to make an idea: it's similar to the way hands cream penetrates into our hand's skin).

I don't remember doing that at all. I remember playing a lot with these, building a bunch of mechanisms with gears.


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RCX firmware download problem
I hope someone can help me with a problem with getting an original RCX 1.0 system working with a current PC.
I bought the RCX 1.0 system back in (I think) 2000 but its been in storage a long time. In the meantime I had children, and now one of them is curious about it and I want to encourage that.
The brick powers-up ok, but the RIS software won't install on my laptop (Win7 x64) and the laptop has no serial port to plug the IR tower into. To work around this I created a Windows XP virtual machine (in VMware Workstation), installed the RCS software on the VM, connected the IR tower to the laptop with an USB-to-serial converter, and bridged the USB port to the VM. This kind of works, in that the RIS software can recognise the RCX brick. However, it says that the firmware is missing and needs to be downloaded. When I do this I repeatedly get a download error.
Update 1: The RIS software displays the message "Initializing and downloading firmware", the LCD on the RCX counts from 0 to 20 ten times, and then the RIS software displays the error "RCX firmware failed to download". I think its trying to download from the PC to the RCS, not from the internet - if I disable the VMs network connection the it fails in exactly the same way and netstat isn't showing any network connection attempts inside the VM.
Has anyone here got a similar setup to work, or has any thoughts on what might be going wrong? Are there any command-line or diagnostic tools I could use to interrogate the RCX and/or upload the firmware outside of the RIS environment?
I'm tempted to just buy an NXT, which will be compatible with modern hardware, but I don't feel ready to give up just yet.
Update 2: I ran a USB sniffer in the VM to view the data being sent over the usb-to-serial connector. Lots of binary data being sent to the serial tower, and some patterns that suggest message framing in an application-level protocol, but nothing I could understand that indicates an error condition. The problem is not at the level of the usb adapter though.
Update 3: In the end I found an old PC with a serial port and the RCX worked without a problem. The RIS software installs and works okay on Windows XP SP2. My thanks to those who contributed suggestions.

The problem could also be that the lego RIS software doesn't actually always support Windows XP. RIS 1 / 1.5 was always a Windows 9x product that used a serial port for the IR tower and therefore didn't even need a Windows driver, yet it seems they went out of their way to make sure it did not work on Windows NT/2000. RIS 2.0 with the USB tower is for 98/ME but claims to work on "a beta version of XP" but it's not officially supported by Lego and no attempt was ever made for Win 2000 support. So maybe a Win 98 would be a better choice for anyone looking to run a VM for RIS.

This did the trick for me.  My situation mirrors the original poster.
http://neuron.eng.wayne.edu/LEGO_ROBOTICS/software_setup_tutorial.html
There are 4 parts to this.  BrickControlCenter (brickcc), a driver for the IR tower, an image of the firmware and some other piece of software called the NCQ.
I did not install the driver since I was using a USB to RS232 adapter and BrickCC worked just fine installing the firmware.
Added bonus, the brickCC is a full on IDE for the RCX.
Also, Swap memory has to be set to at least 4GB because of some limitation on Director 6 which causes the MindStorm program to stall sometimes as it determined that it's 3MB requirement is greater than the available gigabytes if they're 3GB or less.  Clever.

Great. Finally I managed to download the firmware to RCX 1.0

How about running Windows 98 on a Raspberry Pi device and using the Lego IR USB tower that way?
Here is a tutorial on running Windows 98 on a Raspberry Pi.
https://magpi.raspberrypi.org/articles/run-windows-98-on-raspberry-pi-with-dosbox-x
I found this, too:
https://minordiscoveries.wordpress.com/2014/01/20/using-nqc-on-a-raspberry-pi-to-program-a-lego-mindstorms-rcx-brick/

Just went through this exercise on a Windows 10 64 BIT PC.  RCX 1.0 w/ serial IR transmitter.  I am able to get the RIS software running w/o issue on Windows 10 via compatibility mode (256 color, Win 98, etc).  IR port even detects and turns on in the start up tutorial but as described above, initial download of FW clocks the RCX from 1 to 20 several times before failing.  Gave up on this, set up a WinXP VM, and everything works via that.

LEGO Mindstorms was initially released in 1998, running on Windows 95/98, and Windows 2000 and XP were not supported let alone Windows 7.
I know that they did release an updated install CD for the Mindstorms Vision Kit which allowed you to install it on Windows XP (I believe I've still got a copy of this somewhere), however you may be able to install the software and get it running directly under Windows 7 using Compatibility mode - which I know has worked for the Mindstorms Education software (so even switching to NXT won't solve all your pain).

thanks for responding. Thanks for the pointers on compatibility. I hadn't appreciated just how old this h/w is. I chose XP because it was (as far as I know) the first version of windows with good built-in usb support. I'll try using the XP compatibility mode feature, which I'd also forgotten about. (I've tried installing the s/w under Win7 but that didn't work even when I tweaked the compatibility settings).

True. I remember taking the Serial version back for a refund because I couldn't get it to work reliably with my PC, then bought the 2.0 USB based version a year or so later.

I have a similar problem with my RCX 1.0.  Also have a RCX 2.0 that loads the firmware just fine.  After failing to load more up to date firmware I tried loading the original RCX 1.0 firmware from the original CD with a third party tool (ROBOTC) and got a checksum error.  My RCX 1.0 has a hard time getting a signal from the USB IR tower that came with the 2.0 kit.  So I am suspecting the transmission is faulty.  Unfortunately I don't have the original serial IR transmitter to test it with that one.
Although I have the RCX 2.0 I'd like to get the 1.0 going as well because it comes with a power cord.  Nice to have for stationary robots.  According to everything I read the 1.0 line should be compatible with the 2.0 kit - so I am not sure if mine is maybe defective.
It seemed in working condition before I tried the firmware update i.e. still had old programs on there that executed.

The RCX system is fairly old technology which LEGO no longer supports. When you're prompted to download firmware, the download error would be due to LEGO no longer hosting the firmware download.
There are plenty more firmware downloads from 3rd party developers for the RCX, although they may no longer be supported.

ROBOTC for MINDSTORMS
LeJOS

If you're not so interested in the more advanced functionality and the learning curve that comes with it, you may want to invest in a EV3 which is the most current Mindstorms system.

thanks for responding. I've added some more details of the error. When the RIS software says its downlaoding firmware, I think it means downloading from the PC to the RCX, not from the net. Thanks for reminding me about the alternative firmware - I'd forgotten all about them. My reason for persisting with the combination of stock firmware and RIS environment is that I think the RIS visual programming language would be easier for my 7yr old to understand. As a developer I'm happy with C or Java based alternatives, but he would struggle!

Even if you plan to use the regular LEGO firmware, you can upload it to the RCX using third-party utilities. Bricxcc has a page of utilities which can probably help you there. At least you should be able to assert whether the brick itself may be defective or not.


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What is the best way of emulating a Ev3 brick?
The main goal: emulate the work of a EV3 brick so then I would use it as a part of the simulator.
The problem: I don't know the best way of doing this.
About a year ago I asked about the memory allocations in a Ev3 compiled program. Since then I haven't done anything more with this. And now I understand that this is quite a tedious way of emulating brick because I have to write my own "interpreter".
For now I have an idea just to run Pybricks or lms-2012 in a virtual machine with redirected IO (for ports, display, connections, buttons) but I am too witless to do this. For this approach, I would have just rewritten some parts of the original sources so the IO would be redirected to a socket or std. But even this is too hard for me because I am bad at C or ASM.
Then I found some repos where the emulator is already written: wheel, emulator toolkit, RoboSim:

As I understood the first one uses a virtual machine (VM) to emulate the EV3 but I can't understand how it works and why is there Java used (also not sure that this works with an old LEGO MINDSTORMS Ev3);
There is also a VM used (also not sure that this works with an old LEGO MINDSTORMS Ev3);
Probably custom "interpreter" for the LEGO bytecode (also not sure that this works with an old LEGO MINDSTORMS Ev3).

There is also the Virtual Robotics Toolkit that is not an open-source project and also uses a virtual machine (VM) to emulate Ev3. I couldn't decompile the library that works with the VM because it was compiled natively.
So for now the main question is: What is the best way to emulate the work of EV3 brick without having to write/rewrite a bunch of code?
Any help is appreciated, thanks!

After all the time I finally found a good way of emulating EV3 brick. I've tried different ways and this one is the best way I've found:

Bring the original or compat version of EV3 firmware;
Redirect some stuff to be exported (like motors data, sensors data, LCD buffers, buttons, etc.);

The firmware is written mostly on C lang, so for the step we can just export some methods to implement them outside the library

Compile the firmware as a library;

The compilation process of the firmware is done using CMake (useful tool for cross-compiling you code with configurable build steps). Change the output of the build to be a library and edit some other stuff (like dependencies that are presented only on *nix machines)

Import the library in an emulator application and configure redirected data.

In my case I used C# with Avalonia framework. Marshalled compiled library and implemented the redirected functions.

So I did the steps and got quite a good result (for now motor and sensor ports redirects are still under development):

Small clarifications about the project:

For now, the EV3 firmware library is only tested on Windows machines, but when I was rewriting it, I assumed it would be cross-platform;
It can be compiled and tested only targeting x86 because of some problems with pointer size. I've tried to deal with it but understood that there is too much work;
Output/input fuction implementations are still under development;
There are still some small bugs like I can't rename the brick;
Communication with the brick is also not done yet. I couldn't find any resources about emulating USB or Bluetooth. So probably only WiFi would be supported.

For those who are interested here is the source code

Thanks for the answer! While I can't test it to check its usefulness, it is clear that it works for you, which is great :) However, I guess others who would need this answer would not find it as intuitive as it is for you right now. Could you please take a few more minutes to add some more details to the listed steps?


text:
Please help me: Sending String from PyCharm via usb to NXT, which is programmed by Bricx CC
I am new on this platform and hope for some help.
I am doing a school project right now and we are working with Lego Mindstorms NXT and write the program with the Bricx Command Center. I know that this is pretty old but maybe some of you have tips or ideas. So my idea was to create the game rock paper scissors but in a way the player never wins. To do that I worked with the Mediapipe Hand gesture recognition I am running in PyCharm which works great. My webcam analyses the hand gesture.
We have to also work with the Bricx Command Center which works like this: I built a Lego hand and the thumb, index finger, and the rest of the fingers are connected to 3 motors. With those I can make the opposite gesture to the gesture the player made. So when the program analyses the players gesture I want it to send a string via USB to the NXT. The NXT knows the string and makes the corresponding gesture. But that's exactly my problem, because I also need a program written in the Bricx Command Center which can receive the string I send from PyCharm via USB. Are there any ideas or solutions how I could do that? It would be very helpful. I tried many things also asking ChatGPT but as we all know this isn't often that helpful.

Since you are using Bricx Command Center is it fair to presume that you're doing all of this in a Microsoft Windows OS environment?

nxt-python is a popular Python library that can communicate with an NXT via USB or Bluetooth.
Most of the APIs are designed to remotely control the NXT, but the Mailbox feature is useful to send information to a program that is running on the NXT.
I would expect that this should be compatible with the SendMessage and ReceiveMessage functions in NXC.


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Does the color sensor use a camera?
What components are inside the color sensor (37308)?

Can this part be used as a camera, or is it simply a light sensor?

This part has been included in a number of sets since its first use in 2020, including SPIKE sets from LEGO Education as well as the Robot Inventor set. It's purpose is to detect reflected light color, reflected light intensity, or ambient light intensity. Because it can detect reflected light, it can be used as a short-range distance sensor.
We can slide the white and black portions of this element apart to reveal a single PCB inside. Here's the bottom view of the PCB:

The primary microcontroller on board appears to be an STM8S105K6. This is an 8-bit MCU with 32 Kbytes Flash, a 16 MHz CPU, and integrated EEPROM for program storage.
The other smaller components provide support for the main chip and RGB sensor as well as drivers for the LEDs on the board.
On the top side of the PCB we have the remaining electronic components:

On the top side, we have 3 surface mount LEDs to provide illumination and a central RGB sensor. I believe that this sensor is a TCS3472 or something very similar based on its pinout, function, and shape. This part is able to detect light intensity and hue, but it has extremely limited resolution. Here's a diagram of the photodiode array:

This might look like a very low-resolution camera sensor, but the individual photodiodes are averaged internally. Here's what the datasheet says:

The TCS3472 light-to-digital converter contains a 3 × 4 photodiode array, four analog-to-digital converters (ADC) that integrate the photodiode current, data registers, a state machine, and an I 2C interface. The 3 × 4 photodiode array is composed of red-filtered, Green-filtered, blue-filtered, and clear (unfiltered) photodiodes. In addition, the photodiodes are coated with an IR-blocking filter. The four integrating ADCs simultaneously
convert the amplified photodiode currents to a 16-bit digital value. Upon completion of a conversion cycle, the results are transferred to the data registers, which are double-buffered to ensure the integrity of the data. All of the internal timing, as well as the low-power wait state, is controlled by the state machine.

While this averaging setup may improve sensitivity and accuracy, it does not allow the individual photodiodes in the 3x4 array to be accessed. This sensor is certainly not a camera in any meaningful way. It does not appear to be possible to use this sensor to detect even crude shapes, only color and intensity of light.

LEGO Education also has a technical specification document on this sensor (although it isn't very technical). https://education.lego.com/en-us/product-resources/spike-prime/downloads/technical-specifications/


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Can someone identify what set(s) these three bags belong to?
My son just bought a bag of LEGO and it contained these three bags.  Does anyone know what set or sets they belong to? He would greatly appreciate knowing.

Thanks!

It looks like these bags came from 76104-1 - The Hulkbuster Smash-Up:

Those 3 bags can be used to build the Hulkbuster from that set:

The instructions for this are available via Rebrickable.


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Need help to identify a 1x6 support or wall piece
I have looked through pick a brick to find it. I even went searched up the specific set for it but still can't find it.

This is Support 1 x 6 x 5 Girder Rectangular (64448).

The element ID for this is hard to make out in the photo, but it is 6186296.
PaB won't have all elements, especially if they aren't currently in production. This element hasn't been used in a set since 2020. It was last used in the Saturn V remake that is no longer in production.
You can search by element ID on other sites such as Brickset, Rebrickable, or Bricklink to lookup information about a given element ID.


text:
Alternative to LEGO Education for Technic parts?
I am trying to work through the LEGO Education platform, however am stuck at where to buy a big set of gears and similar from.
There are sets of 50pcs for $40+, which is clearly a ripoff. Or 500 pieces for $100+. Clearly I'm not willing to go broke for some plastic pieces, hence the question.
How did you obtain a good amount of... pretty much all the basic parts?

I'm not sure what your use-case is here, but LEGO Education is probably the most expensive way to simply buy parts. When you purchase from LEGO Education, you are also paying for access to a bundled classroom curriculum in addition to the parts you are buying. In essence, these shouldn't be valued in $/part, but something more like $/hour of learning experience.
If you are looking to design your own learning experiences, or you just want a pile of bricks for students to engage with, LEGO Education is likely not the best value. In this case I'd recommend buying regular sets that roughly match the part profile you are hoping for. If you are comfortable buying used parts, then I'd recommend sites like Bricklink, BrickOwl, or eBay.
This related question may also be of interest:
What's the most cost effective way to buy bulk LEGO bricks?

Thank you for your answer

Actually, even LEGO PAB (Pick A Brick) can be a good choice- https://www.lego.com/en-us/pick-and-build/pick-a-brick?query=gear&system=TECHNIC&page=2
The link is a simple search I did for Technic gears.

Thanks to you too.


text:
D11 Test mid build
On step 198 of D11 Technic set the instruction asks you to test the gears. When I test it, the gear switches but never runs the test to spin the right gear. It does that on each gear it tests.

I tried to check if the gears work by advancing to calibration, although the set is not finished. It correctly picks the gears to calibrate the "shovel". I am lost. It looks like an app issue.

I have the same problem with my D11, have you figured it out? Itchy head now


text:
Seeing if anyone can possibly tell me what brick this is
Trying to find out what kind of brick this is for a wedding book that I'm trying to make and will need quite a few of these.

It is Brick, Modified 1 x 2 x 1 2/3 with Studs on Side (22885)

To expand on Alex's answer, an example of it being used can be found in set 60243 - Police Helicopter chase

Thanks for the Answer. I edited the Alex answer for later.


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In Studio, when switching color filter to "Available colors in BrickLink" all bricks have no color available and pricing is missing
As soon as I switch color filter to "Available colors in BrickLink" all bricks have no color available - even what I assume are the most common brick types... I also appear to receive no pricing information for any brick! This must be some kind of error of correct live information feeding into the application - do you know how I can check and I solve this?
This is on BrickLink Studio version 2.23.12 (1)

Your question is missing some important information that would be useful for being able to answer it. I'm presuming you are using BrickLink Studio, but you should make sure to state that as well as the version (From the Help menu, select About Studio) to make sure that people will be able to answer accurately.


text:
Identify set that multicolored bags without a box came from

I have 8 bags that simply have an "05 in a triangle with PP under it" and "2021 The Lego Group" on them. Looking to find what set they are from so we can download the instructions.

A lot of the smallest sets came in bags without boxes. I think the Lego pieces in those bags must come from one of the "classic" sets, that is, the sets mainly consisting of plain Lego bricks and having no instructions for a specific model. These are the creative sets which encourage building whatever you want, rather than a prescribed model.

The contents of the bags are consistent with set 11014 "bricks and wheels":

In particular:

Blue 4 x 6 plate
Bright pink 2 x 3 plate
Light Bluish Gray Wheel 18mm D. x 14mm with Pin Hole, Fake Bolts and Shallow Spokes
White round 1x1 tile with squinting eye pattern

However, the two top bags do not match the contents of that set - I believe they belong to set 11013 "creative transparent bricks" instead, due to:

2 of 2x2 flower, solid stud in yellow
2x2x2 container box in white
2x1 plate with 3 teeth in white
2x1 brick without bottom tube in trans-bright green

Once you have the set number, it's easy to search for instructions in the Customer Service section of the LEGO website.


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How should I go about selling a large number of unsorted LEGO sets?
Here is my problem.  Over the years my son had me buy a large number of Star Wars sets (including 10179, 10188, 6211, 7676, 7675)  and he built them.  Then he traded (or lost) most of the mini-figs except for those in the death star.  He has all but 3 and they are for sale on e-bay.
They all were taken apart and I am sure that 99% is in all of the 10 plastic staorage boxes I have.
My problem is how do I sell them and what to ask?  I see that the 10179 is going for 2400.00 new in box.  Really? Who would pay that much. It is just a Lego. I have a huge list of other star wars kits totaling 24 in all.  I can get all the kit numbers if you like.  Plus, I have 60-100 dollars of gift cards for the LEGO store that I will throw in to help get missing pieces or whatever from LEGO itself.
I am in the Sacramento area of California and found this site.  Thought I would throw it out there.

No offense, but on this site, it's never "just a Lego".

See also the awesome answer here: https://bricks.stackexchange.com/a/9718/56

You have three basic choices, depending on how much time you want to spend:

Sell the collection as-is (with as much honest description as you can muster and great photos if you're selling on-line).
Sort the collection into sets and sell them as-is with parts / figs missing.
Sort into sets and replace missing parts / figs.

These three are not mutually exclusive.
Personally, I'd go with the first option unless you have a lot of time on your hands and are a real enthusiast. Otherwise, your time is probably worth more than any additional profits you might make. At the same time, there are plenty of us who would love to take on a collection like this.

I recently took the second route you suggested when sorting a collection of bricks I found at garage sale sources. There were some instructions included but one of the main reasons I took that route was because it seemed that there might have been more sets in the unsorted mess than the instructions along would have lead me to believe. I doubt that this is the case here however, as it seems that the questioner has kept track of what sets are (mostly) there.

One of the issues I see is that you're missing most of the minifigs, these generally aren't available individually through the LEGO store.
As you've seen for a complete boxed set of some of these kits are very expensive to buy second hand; they are no longer in production and some people are willing to pay that much to own them.
In terms of selling what you've got, if you can sort them back into their correct sets that would help in terms of maximising your potential profit, however there's clearly a trade-off with your time to do that. If you do go down that route there are a number of sites that have inventories for most sets, even the older ones that don't have them listed in the manuals:

Peeron Set Search
Brick Link Star Wars Sets

Brick Link is the site to use for selling LEGO bricks, many sellers on there sell bricks individually (albeit with a minimum order), which may be an option but is quite a lot of work. Alternatively you could try contacting a local seller and see if they are interested in taking your stock on.
Finally you could look into finding some local brick fairs and trying to sell it there, either in bulk or parts.

Unfortunately, what you have is a gigantic pile of unsorted LEGO that came out of sets that you originally spent nearly $3,000 on.  With a gigantic pile of unsorted Lego, that may have a couple of minifigures in it, you probably won't get very close to $3000.
You can try your best to get them sorted into their original sets, but your best bet is to create 1 pound lots and auction them on Ebay, or try to sell them individually - you might be able to offer them for sale for something like $10 per pound, or more.
If you try to sell the entire lot all at once, you are probably going to see offers come in at around $5 per pound.
Sorting used LEGO is a lot of work, and if you aren't willing to do it - you'll take a hit in terms of what you are likely to get.

You should check the value of the used sets on this site:
http://www.brickpicker.com/
For 10179, you can get easily 1600$:
http://www.brickpicker.com/bpms/set.cfm?set=10179-1


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What are the electrical properties of electric LEGO systems?
Several electric LEGO systems exist:

LEGO Trains
LEGO Technic Power Functions (PF)
LEGO Mindstorms (in several versions)
...?

How do these systems differ in electrical properties and which systems can safely be connected? I am especially interested in the number of wires (2 or more), the Voltage level (V), and the average and maximum current allowed (A).

This is a big question, but here's an overview of the main electric systems.
4.5V (1966 - 1986)

The original 4.5V system worked with 3 x 1.5V C cells. It was produced between 1966 and 1986 and was used to power motors and lights in a wide variety of trains, technic, basic and even DUPLO sets.
12V (1969 - 1993)

Coexisting with this system, a 12V standard for LEGO Trains was introduced in 1969 and produced until 1993. The power was supplied by DC Transformer. There is no electrical compatibility between 12V and 4.5V components, and the higher voltage can damage the lower-rated parts. In addition to motors and lights, an assortment of other 12V accessories were available such as automatic switch points. The 12V system had two wires or three wires for track switches.
9V (1985 - 2008)

9V became the LEGO standard in the early 90s. There were several different power sources, such as a single 9V battery, 6x 1.5V batteries and a DC Transformer (used exclusively for trains). The 9V system is electrically incompatible with either the 4.5V or 12V systems, but as I understand it, 9V components are electrically compatible with each other. 9V was a 2-wire system. Philo's web site provides electrical details of a variety of 9V motors.

The first generation of Mindstorms, the RCX generation, was again based on 9V. The original 1.0 version could be powered using a 10V DC transformer, but later versions took 6xAA batteries. It used standard LEGO 2-wire 9V connectors. When powered, the sensor inputs can supply power (at a bit less than 9V). More details of the electrical characteristics of these ports can be found in Claude Baumann's Making Your Own RCX Sensors. The same sensor interfaces were also used on the earlier and less well-known Lego DACTA Interface B but unlike on the RCX powered and unpowered sensors used different ports on Interface B (this is why powered and unpowered sensors were different colours).
The RC system was introduced in 2006. The RC system uses 9V components but generally includes a remote and a chunky RC brick that peripherals can connect to.
Power Functions (2007-2021)

Power Functions (PF) use a 4-wire system, the outer two wires providing power and the inner two control functions. Once again, it is nominally a 9V system, although it will cope with some variation to accommodate various types of batteries. For example, the 88000 AAA Battery Box uses 6 x AAA to supply up to about 9.6V and up to 800mA current, depending on the batteries used, whereas the 8878 Rechargeable Battery Box delivers 7.4 V at up to 1.1A (?).
Lego sold an extension/adapter cable that can be used to supply old 9V devices from a power functions source. It can also be used to supply ordinary power functions motors from an old 9V source but not to supply power functions IR receivers or server motors. See Does the LEGO "Power Functions Extension Wire" (8886) work in both directions between old 9V and new Power Functions devices? for more details.
Mindstorms NXT and EV3 (2006 - 2021)
The Mindstorms NXT system is a 6-wire system. Two wires retained the 9V motor and sensor systems from the RCX while the other four provided tachometer functionality on the motor ports and a digital sensor interface on the sensor ports. This system was available from 2006 to 2013.
The Mindstorms EV3 uses the same 6-wire connectors as the NXT but additional functionality and an auto-detect system were added. Unfortunately in doing this, they broke compatibility with 2-wire devices. EV3 was available from 2013 to 2021.
Lego sold an adapter cable for going from the NXT to the old 9V connector. This allowed old 9V motors and RCX sensors to be used with the NXT. It also allowed NXT motors to be powered from a 9V source (obviously losing the tachometer functionality) and the NXT touch sensor to be used with RCX or Interface B. Unfortunately, this cable doesn't work correctly with the EV3.
Powered Up (2016 - Present)

Begining in 2016, products across all product lines began using the same electrical standard. This change began with WeDo 2.0 and eventually grew to include Trains, Technic, and Mindstorms.
This system goes by many names, including Powered Up, Control+, LPF2, WeDo 2.0, BOOST, and Robot Inventor. Hubs and peripherals from these systems are generally compatible with one another.
This system includes hubs that can be controlled via Bluetooth, allowing apps to control most sets.
Electrically, this system is still 9 volts, but the connector and signalling are not compatible with any of the previous 9v systems. An adapter has never been produced to connect this system with older components.


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How can I find out what parts are in a Lego set?
I am building an inventory of all my LEGO pieces and I am looking for a website that can give the pieces in a set with only the set number. It would be easier if there was information for many LEGO sets with the full inventory. I also will need to have a file of all LEGO parts.

I have found a file that may help. Here it is. I haven't looked at it yet. I'll add it as an answer if it is right.

Peeron sounds just like what you're looking for. You can add sets to your account, and view how many of a certain piece you own, and in what colours.

Peeron USED to be awesome. Then, one day, I came home with some new sets and Peeron HAD NO CLUE. That was about three years ago, and the only sets I've added since then are the architecture sets, since they were seriously easy to remember. So, currently I'm adrift in the inventory department. frump

Here are the options that I'm aware of along with some basic pros and cons:
Rebrickable
Rebrickable provides set inventories for nearly all sets. It includes sets from all time, and is still being updated as new sets come out. Rebrickable also provides all set inventories for offline use via its download page.
Bricklink Inventory Reference
Bricklink probably provides the most complete and up to date set inventory data. These inventories are also very detailed and include extra parts, sticker sheets, etc. If you are a seller on Bricklink, you can also part out sets into your inventory which could be useful to you at some point.
Brickset / Lego.com
TLG provides nearly complete inventories for sets online via the replacement parts page. You can use this to get part information from your sets, but the interface is lacking because this isn't really what the page is meant for.
Brickset provides this same part data in a format which is much better for viewing. Simply search for a set and use the "Parts" tab to view contents if they are available.
These resources have a couple of downsides:

They only include relatively new sets.
Set inventories aren't as complete as Peeron or Bricklink.

Peeron
This site is great for old sets, but it isn't updated anymore.

I use Rebrickable and have found the site-owner to be very friendly and open to feedback. As you point out, the philosophy is to help build sets, not to catalog each variation of a piece. For that reason, the site originally did not distinguish between some colors such as the "old" and "bley" tones of gray. I see the site now does distinguish between them, but unfortunately for me I had entered the bulk of my collection before that.

Try the bricklink catolog. They also have inventories like Peeron, but
a little bit more detailed (like part variations)
and also include stuff like extra parts and Ninjago cards.


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Third-party blocks with a smiling face or an umbrella with 2 dots on each side
I bought a bunch of duplos from the thrift store and inside there was not Just duplos but also mega bloks. I was able to separate most of them but there are a few that I just cannot tell which is which. They have a logo in the middle  of the stack but its a picture rather than a word.  I'm trying to find anything online but am having no luck. The logo almost looks like a smiling face or an umbrella with 2 dots on each side.

Could you add a picture?

I tried too but it says I need a reputation of 10 so it will be a while before I can add one.

I uploaded an image of blocks with the mystery umbrella/smiley/anchor(?) logo. The blocks don't have any other indication on them of manufacturer, although based on the collection they were found in, I would estimate they were sold in the mid-1980s.

Yes, that's the logo! As for an information I'm still looking but coming up with nothing. They don't feel like a megablok does they feel more like a duplo but that's about all I know about them.

After some searching, I have finally come up with the brand.
I too purchased a lot of bricks and found these odd ones in the mix, they are Tandem bricks, and there isn't too much information out there on them.

Since you didn't link a source, I will: http://bloks.hyperboards.com/action/view_topic/topic_id/1292

All Duplo and LEGO bricks have the LEGO logo (the logo is just the word LEGO) on the brick somewhere, usually on a stud. Megabloks always have blank studs and slightly offset colors compared to LEGO or Duplo bricks.

Although the logo on the "umbrella-bricks" you have are not Megablock, they are not Duplo either. Duplo always have the LEGO logo somewhere, and the studs are hollow. The hollow studs make them compatible with standard Lego bricks that are at least size 2x2, since the cylinder inside the Lego brick fits perfectly inside the hollow Duplo stud. See the locomotive on this image where it has some 2x4 Lego bricks on Duplo bricks:

Also see this answer on another post for more details on Duplo piece information.


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Is there a way to glue already built sets?
My son who is now 16 no longer plays with his Lego sets. He would like to preserve some of his larger sets like Jabba the Hutts sail barge. Is there anything we can spray or paint on to hold them together? Or do we need to take it apart and glue it?

@Acleverlegochild One of the key lessons in Lego for children is scarcity. Sometimes you have to make do with the pieces you have; this forces kids to come up with novel solutions to problems. Thus I'd recommend not buying more and more lego unless your kid's work is truly genius. Most people just take lots of pictures and post them on Flickr.

My son (4) and I love all the Star Wars sets and play with them, a lot! We go in to battle with ours. Glueing them would be perfect so there are definitely reasons for doing it.

Although it can be done (I will share below), I would sincerely discoure you from gluing your LEGO sets. You will very much regret it later. Here are the reasons why: LEGO is meant to be a building toy - put together and taken apart many times. Once you glue a set it completely looses its usefulness and becomes nothing but another item to take up the shelf and collect dust.
LEGO has generational value. Your son may have lost interest now (very common in teen years), but may want to get back to the hobby later. He will definitely regret gluing his sets. Also, even if he doesn't get back to the hobby, if he will decide to have kids in the future, they will greatly appreciate having the opportunity to play and build with LEGO. Many LEGO fans inharited their LEGO sets from their parents and even grandparents. The long-term value of LEGO is truly amazing.
And this brings up the third point against gluing LEGO. The sets you mention have significant value that will only rise when the sets get retired. If your family ever gets into financial trouble and need to get some cash quickly, you can sell those LEGO sets - but not if they are glued.
I would encourage you to consider just boxing the sets (either built or taken apart) and just store them away carefully. It is really your best option that would keep both the value and the usefulness of the sets.
Having said that; if you still want to glue the sets, yes, you will need to take them apart and glue them. The most gentle glue that would not damage the LEGO elements too much but will hold the model together is simple white school-glue. You only need to add very little in between elements so the glue doesn't come out at the edges.
Another option is to just wrap the whole set in thin plastic sheet (the kind used for wrapping food). This is more for storage and moving the set around, but the tight-fitting plastic prevents the set from falling apart.

This post is 100% right re the generational thing. I have sets from 20+ years ago that my 2.5 year old son and I are playing with right now.

-1. The answer to a viable how-to should never be "don't", especially not for reasons the asker may not care about.

Both myself and others have listed options for gluing and similar methods. I added reasons not to glue LEGO, because OP may have not considered them, and so many people regret the decision later. If OP truly didn't care, he/she would have probably mentioned that in the original question. It's better to be safe and provide additional information, then omit important considerations that OP might find helpful in weighting the pros and cons of their decision. However I do agree that I could have listed the options in a different order for a better answer. I will keep that in mind for the future.

A better way to preserve LEGO is to put it in some sort of display case. It maintains the value and keeps the dust off.

Use MEK (Methyl ethyl ketone). Can buy it in hardware or auto body shop supplies. In auto body work it is used to degrease and clean adhesives off surfaces. It is also a major component of ABS plastic cement, which you can also use but it's messier. You can also put a bit of MEK in a glass jar and then throw in old lego pieces to create a filler and cementer. But that is a rare thing to need.
I use an eye dropper bottle (glass of course) or glass syringe to glue parts together. You MUST be in a well ventilated area, and I mean well ventilated.
MEK melts plastic so put the pieces together before it evaporates. If your eyes are near MEK they will be bloodshot, so have a fan or do this outside, like I do. Also wear those cool blue non latex gloves to protect your hands.
I use MEK to glue major structures together that fall apart - like supports. In tall structures I will glue the structure into two halves so that they can be stored partially unassembled, and then put back together. It is also useful to glue things like space shuttle parts that continually fall off when played with. I never glue all of the pieces, just the major parts that support the toy, that way it can still be disassembled.
MEK works great and I love how it keeps builds together that would otherwise be lost forever in masses of parts stored in bins and tubs.

I have Lego sets that have been on display for years, including the relatively fragile AT-AT from 2003. It has stood, fully assembled and almost never touched, since I first got it in late 2003/early 2004. In all that time it's gotten dusty, so I've used various things to clean it: a vacuum with a brush (if you're sure there are no loose parts), a can of compressed air, and a sink of soapy water. You can submerge this whole model, or take parts of it apart, and wash the dust off, in a few minutes.
At the end of the day, it is still in near-perfect condition, because it's never played with and just sits there. I never, ever, wish it had been glued. Why would it need gluing? I can always put it back together if anything falls off. The lego pieces hold themselves together just fine.
There are two areas where its preservation is lacking: First and foremost, sunlight. Sunlight changes the colour of the bricks. I keep this one out of direct sun and it hasn't yellowed too much. But the light-grey pieces are particularly prone to discolouration and I'm sure the outer shell of the model has changed colour somewhat. The only thing that would have helped is UV-protection.
Second, some of the technic pins that hold it together have weakened over the years. These can be easily replaced if they become a problem.
Otherwise, this model has stood as a display piece for 10 years now, but if I wanted to, I could disassemble it and use all its pieces in a new creation.
I offer this as evidence that you do not need to glue models, and as TheBrickBlogger wrote, while it's possible, I would discourage it. It doesn't "preserve" the model in any useful sense, except keeping it together so that no pieces get lost or missing. If the model isn't going to be moved around a lot, or played with, nothing will fall off. And if something does fall off, it can easily be put back.


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How can I get replacement stickers for a new lego set?
I recently bought a Lego Fire Boat (set number 60005) but for some reason, when I opened the box and shook out the contents (as I normally do) no sticker sheet fell out. I was wondering if you could help me out here, as this set is the jewel of my crown. I need them to create a (rather unusual) fire rescue MOC and film but I cannot do this without the stickers. If you can help me here, it'd be much appreciated. Thanks guys!
Ciaran
P.S. can you give me somesolutions?

Although this question is specifically about new sets, the answers in the question flagged as duplicate are valid even if that one is about an older set. Besides, the solution goes for any product you buy: not satisfied? Go to your reseller and explain the problem. Failing that, contact the producer. The LEGO customer service is very friendly and their number is on the box you bought.

LEGO Customer Service will be probably be happy to help you out. They've been happy to replace missing or broken parts for me in the past. They have an online service for requesting replacement parts here:
https://wwwsecure.lego.com/en-us/service/replacementparts
I don't think sticker sheets are listed in the inventories on that page though, so you'll have to add it manually using the "I can't find what I'm looking for" link at the bottom. Once the sheet is added to your cart, you just need to checkout and provide an address for shipping purposes.
If you have any problems, you can also contact customer service directly from this page:
https://wwwsecure.lego.com/service/contactus/

Link rotted away, this seems to be the new one for replacement parts:  https://wwwsecure.us.lego.com/en-us/service/contactus


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Ideas for large NXT projects
I currently have 6 NXT sets. Can anyone think of some large scale projects that I could attempt using most of the NXT bricks and pieces together?

I don't think this question should have been closed.

One interesting project would be to build a manufacturing process, e.g. use the 18 motors to automate the production of little Lego cars or planes. It's a big project though, I once started building a factory to assemble little Lego planes with the Lego sets from a summer camp I was working at, but the kids started complaining that I was using up all the pieces :)


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How do I get started with Mindstorms NXT 2.0?
I need help programming a NXT 2.0 Lego Mindstorms. I want to make the robot turn, stop, go back, etc. when the color sensors see certain colors. For example when the robot sees red it stops then turns. Please help me I am new to Mindstorms and programming.

As such, this question isn't exactly a good fit for this Q&A site, as it's too generic in nature and doesn't give information on what you actually tried. The best way for you to learn is to start using the Mindstorms kit and following the instructions (LEGO did a good job with it so that children should be able to start by themselves without help). If at some point you encounter a specific issue which you can't solve by yourself, then you'll probably be able to ask a more specific question. The FAQ explains which questions should be asked here.

As was pointed out, this question is not specific in nature, so it's hard to give a definitive answer. If you haven't already done so, it would probably be helpful head over to Lego.com and grab get the NXT 2.0 User Guide and perhaps begin looking through the sample programs.
This book may also be helpful to you:
The LEGO MINDSTORMS NXT 2.0 Discovery Book: A Beginner's Guide to Building and Programming Robots
If you run into specific problems as you are getting started, feel free to create a new question, and we'll try to help you out.

Books are indeed a very good starting point, I'd also recommend The King's Treasure. Although I've only read the previous one (Mayan Adventure) from James Kelly, I found it very educational.


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Guide me on how to use my Mindstorm RCX kit on OS X Mavericks
Any suggestions on how I can use my old RCX set on Mavericks? I have set up Xcode command line tools, and I am getting compiler errors while trying to download nqc through Macports. Even downloading gcc49 through Homebrew has not helped fix this issue. Is there any other option I'm overlooking?

I struggled with backwards-compatibility with NQC myself. A couple months ago I made the switch to leJOS, so far its been great.

Thanks for your response Keshav. I'd ideally like to stick with NQC but even leJOS is giving me issues. Despite setting up the PATH variables correctly, I keep getting "clang: error: no input files" errors when running Ant. Fiddling around with the main build.xml and build.properties files also does not seem to work


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Advanced coloured lines following robot
I am trying to build a coloured lines following robot, and I would like to know what kind of sensors do I use for my robot to differentiate and detect several different coloured lines?

What hardware/software are you using (NXT, EV3, etc..)?

[ObGrammarJoke] Why does the bot have to be coloured?

@gev Ba-dum Tish!

If you are using the EV3 Sensors you should use the EV3 Color Sensor which can detect 8 colors (colorless, black, blue, green, yellow, red, white and brown). If you are using the NXT I would recommend the HiTechnic Color Sensor or HiTechnic Color Sensor V2... I hope I could help.


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Duplo Activity table to Lego System Table
We purchased a table with Duplo baseplates on top (activity table) for my son when he was 1 year old. He's now turning six and we would like to convert the Duplo top to the regular LEGO System top. is there a baseplate that has Duplo studs on the bottom (so it sticks and essentially covers the Duplo spaces) and regular LEGO System studs on the top (so that the table can be used with the regular LEGO System pieces. It seems like a shame to chuck the table.

Don't forget to accept the answer if it works for you!

To answer your question, no there is no such plate with DUPLO tubes on the bottom and LEGO studs on top. HOWEVER regular LEGO and DUPLO are completely compatible - as long as the regular LEGO bricks are at least 2x2 studs. Just cover the DUPLO table with regular LEGO bricks and you are done...(c;
You could actually use regular LEGO plates too, however the connection won't be as secure as with regular LEGO bricks as plates are much thinner so won't go all the way down to cover the LEGO studs. But they do fit, and their benefit is that they cover a much larger area so you would need less.
Here is an article and some visual examples of how LEGO and DUPLO fits together very nicely: http://thebrickblogger.com/2010/12/lego-duplo/

you are awesome!!!! I'm going to try that now...now just have to scrounge enough flat duplo plates 2x4 to fill the top :) thanks! The reason for this is that that top has solid rounds and not the originall duplo round to connect to the system so your idea worked when I placed the flat duplo on top first and then use the regular system bricks :) so I am figuring if I get a could of duplo base plates and put them on top first, the table would be good to go I think :)

Marisabel, that sounds like a plan! You can get some quite large DUPLO plates on BrickLink so you don't have to work with a lot of smaller ones (4x8, 6x12, 8x8 and 8x16). It is just something to consider investing in in the future. You can find them here:  http://www.bricklink.com/catalogList.asp?v=2&pg=1&catString=487&catType=P

You can use the large bricks such as the 12x24 to build the surface of the table. This will give it better stability and should bind correctly to the underlying duplo, plus it saves time in assembly.

Some additional notes: Marisabel is right that the duplo table has solid studs (not compatible with normal legos) when every other duplo brick has hollow studs, so you need a layer of duplo and then a layer of standard. I just ordered bricks to convert a duplo table to standard legos, it needed 12 standard 8x16 plates (tall enough to fit the duplo studs) and 12 duplo 4x8 plates.

Unfortunatly this is problematic.
Duplo baseplates generally have flat-topped studs, these studs are incompatible with lego. Furthermore thin lego plates don't have enough depth to take up a duplo stud.
So you are looking at at least two layers for the conversion each at least one full leog brick thic. The lower layer would be duplo plates (one lego brick high) followed by a layer of regular lego bricks. You can get oversized lego bricks which would probablly help in making it less likely for your conversion layers to come apart.


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Pass sensor or motor port number as a parameter
I want to create a block for one light sensor or one motor separately. Is it possible to give the number of the port as a parameter to a sensor or motor block via data wire? In NXT-G it was possible.

Yes, it is possible to pass the port number as a parameter to a sensor or motor block via data wire. It's just that it's manually selected by default. To change this, go to the port of the sensor or motor block, and select the top-most option which has the plug icon on it:

It will then create a data port for which motor port you want to use:

The same principle applies with sensor blocks. The input for both sensor and motor blocks is read as number, and you can validly enter a number 1-4 to represent which port.

In the above example, a variable is created, and that variable is then passed to both the motor and sensor blocks. Since it was set as 1, it will move motor connected to port A, and wait until the touch sensor connected to port 1 has been touched.

I just test with my EV3 with version 1.2.2 and V1.09H firmware I have connected motors to Port A B C, and number 1 to controlling motor at port A, not 0 so the result is 1-4 mapped to port A B C D Hope this helps.

Thank you so much for the correction @dogwong! I have edited my answer to correct this.