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Lego's 0.002mm specification and its implications for manufacturing (2025)

thewave.engineer

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Re: Lego's 0.002mm specification and its implications for manufacturing (2025)

#281

Post by mmustapic »

mcphage wrote: post #250
sixo wrote: post #222

Earlier quoted context omitted.

Prices are constrained by demand moreso than by cost of production. Lego pieces are expensive because they can be, they still sell, and this is largely due to the quality. As long as the quality moat persists, they can charge as much as people will pay, and--good for them! That you personally would prefer lower prices does not mean they "should" be lower. Those lower costs of production, to Lego company, "should" mea…

> As long as the quality moat persists The risk Lego faces is that they don't actually have a quality moat any longer. You can get non-lego sets with no stickers, plenty of prints, LED lighting, at a cheaper price, and with the exact same piece quality. I purchased this set: https://www.lumibricks.com/collections/steampunk-world/produ... over Christmas, and I paid $105 because it was on sale. The pieces were indistin…

What you mention is true, but Lego sets are (almost always) very well designed, specially the ones for kids.

Re: Lego's 0.002mm specification and its implications for manufacturing (2025)

#282

Post by Freak_NL »

jimmar wrote: post #47

I've never regretted buying Legos for my kids. Yeah, the kits can be expensive, but they last forever. We've thrown out or donated lots of old toys, but the Legos will never be given away.

In terms of toys which my son got from my childhood, Duplo and Lego stick out. We kept everything; booklets and parts. We built the classic town square (set 1592) recently, and we've got all the parts, including the statue bits! Only the printed lettering on the sign's 1×8 white brick had faded.

Sure, some puzzles and books survived, but the Lego stands out. If he ever has children they are in for a treat…

Re: Lego's 0.002mm specification and its implications for manufacturing (2025)

#283

Post by jjk166 »

> They're cut from hardened steel using wire EDM, a process that erodes metal with controlled electrical sparks, achieving tolerances within a few microns.

They're made by sinker EDM, not wire. The physics are similar but it's a radically different process.

> But in an assembly system like LEGO's, small errors accumulate. Stack ten bricks end-to-end and the cumulative tolerance is ten times larger.

That's not how these tolerances work. The super tight tolerance is the interference fit on the stud. This is a diameter. You don't stack diameters together. Each connection is independent. Where you can get tolerance stackup is brick height and stud spacing. Although even here random errors tend to cancel out as you mix lots.

>LEGO's system reveals timeless truths about manufacturing. Process control beats precision machining. A stable, repeatable process produces better results than chasing the tightest possible mold tolerances. Invest in monitoring rather than just tighter specs.

The whole article says the opposite. Lego relies on precision machining and tight tolerances. Process control is necessary in addition to these.

Re: Lego's 0.002mm specification and its implications for manufacturing (2025)

#284

Post by post_break »

jjk166 wrote: post #283

> They're cut from hardened steel using wire EDM, a process that erodes metal with controlled electrical sparks, achieving tolerances within a few microns. They're made by sinker EDM, not wire. The physics are similar but it's a radically different process. > But in an assembly system like LEGO's, small errors accumulate. Stack ten bricks end-to-end and the cumulative tolerance is ten times larger. That's not how the…

The whole article makes me mad when they factually get so much wrong. Like I had to stop reading.

Re: Lego's 0.002mm specification and its implications for manufacturing (2025)

#285

Post by conception »

georgefrowny wrote: post #157
scatbot wrote: post #12

Lego is one of those companies that is simultaneously amazing and kind of sucks. On one hand the core product is incredible. The tolerances on the bricks are micrometer-level precision and the fact that pieces from the 70s snap perfectly into ones made today is mind blowing. On the other hand, a lot what the company does today just sucks. Set prices are outrageous. Printed bricks get replaced with stickers and many s…

In terms of creativity of model options, the Chinese compatibles are stomping them. You can even get a model of post-explosion Chernobyl. Not to mention all the sci-fi tie in from Star Trek to Warhammer that real Lego hasn't signed contracts for. But if you want an 60cm Gloriana class, there it is. Plus Technics-ish sets and bulk boxes that aren't 75% special body panels that only fit that specific model, since Techn…

When you build a knock off set, though, you can tell that the Lego versions have so much more thought put into the actual build process and the stability and functionality of the finished product.

Re: Lego's 0.002mm specification and its implications for manufacturing (2025)

#286

Post by conception »

scatbot wrote: post #12

Lego is one of those companies that is simultaneously amazing and kind of sucks. On one hand the core product is incredible. The tolerances on the bricks are micrometer-level precision and the fact that pieces from the 70s snap perfectly into ones made today is mind blowing. On the other hand, a lot what the company does today just sucks. Set prices are outrageous. Printed bricks get replaced with stickers and many s…

Set prices are a lot more reasonable if you stay away from the branded options, Disney and Star Wars sets, especially have a intense premium associated with them.

Re: Lego's 0.002mm specification and its implications for manufacturing (2025)

#287

Post by skyberrys »

scatbot wrote: post #12

Lego is one of those companies that is simultaneously amazing and kind of sucks. On one hand the core product is incredible. The tolerances on the bricks are micrometer-level precision and the fact that pieces from the 70s snap perfectly into ones made today is mind blowing. On the other hand, a lot what the company does today just sucks. Set prices are outrageous. Printed bricks get replaced with stickers and many s…

The smartphone dependent is a line to not cross. Anytime we get the phone dependent sets they are returned and analog toys are chosen instead.

Re: Lego's 0.002mm specification and its implications for manufacturing (2025)

#288

Post by jazzyjackson »

CapricornNoble wrote: post #274
tokai wrote: post #176

Earlier quoted context omitted.

You trust the Chinese knockoffs not to leach out poison?

Yes. What "poison" do you think they are leaching? Has anyone ever done any instrumented/lab testing that has shown ABS plastic toys to pose a threat?

I don’t know enough about plastics, and if it’s ABS it’s ABS, but how is it dyed? Point is I don’t know, so I buy from a company that has a reputation and would be held accountable, and would never buy kids toys from a fly by night business with no reason to care how carcinogenic their product ends up being

Re: Lego's 0.002mm specification and its implications for manufacturing (2025)

#289

Post by skyberrys »

fifilura wrote: post #239
cruffle_duffle wrote: post #192

Earlier quoted context omitted.

Sorting Lego is such a pain in the ass. I have like a huge stash from when I was a kid. Back then we just had it all in a few tubs and dug to find a part. But somehow now I feel I must sort them… but the “right way” is ill defined and kind of sucks the joy out of playing (especially disassembling) And there is no “right way” that I’ve even found. Sort by color and now the little pieces fall to the bottom and are hard…

The evolution of lego sorting [2001] https://news.lugnet.com/storage/?n=707 (Bah Might as well submit that as a top level story, others may enjoy it)

Yeah go for it! I'll add a comment though, now we are working on automated shifting bins with stacks of different size grids to filter the littles to the bottom and still easily pick up the top bigs to see them. There was been a discussion (by my children) about something involving a Lego vacuum they saw online.

Re: Lego's 0.002mm specification and its implications for manufacturing (2025)

#290

Post by SV_BubbleTime »

jjk166 wrote: post #276
SV_BubbleTime wrote: post #220

Something that took me years of working with custom plastic injection part experience to notice still kind of shocks me… Legos don’t have draft. That means nothing to 99% of you, but someone else here must understand what the implications of that are for releasing from molds at a mass scale.

Actually they do have a draft. The bricks are designed so you don't notice it, both by the draft angle being quite small, and the parting line is moved up slightly so by the time you get to the bottom of the brick you're back to the original width. https://medium.com/@bsather/breaking-down-the-perfect-design...

I was annoyed at this one time so I took two legos and put them under the microscope. I couldn’t see it. Which is just to say how fucking tiny the scales are here.

For production parts we’re looking at drafts around 3 degrees. Which is… not what they have even considering the tuck back in!

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