Laser Cut LEGO In MDF

It’s hard not to be a fan of LEGO. The humble plastic bricks from Denmark enabled many a young engineer to bring their architectural and mechanical fantasies to life. But one limitation was that you were stuck using the bricks LEGO designed. Thankfully, [John Sokol] has come up with a way to laser cut his own LEGO-compatible bricks, and provided the tools so you can do the same.

After hacking an OpenSCAD script to generate just the top pins of the block, [John] exported an SVG into Inkscape so that he could scale the pins properly before exporting a final PNG for the lasercutter. Using RDWorks, [John] was able to find an engraving setting that worked well with dry-erase whiteboard MDF — an unusual material for a brick, but functional nonetheless. The key here is that the engraving setting takes away just enough material to create a raised pin on the part, without cutting all the way through the MDF or burning the surface.

Despite some damage when removing the work piece from the laser cutter, the part mates up well with the official LEGO brand parts. We’d be interested to see how the MDF cut parts hold up over time compared to real LEGO bricks made in ABS, which seem to last forever.

This isn’t the first make-your-own-LEGO hack we’ve seen – maybe you’d like to 3D print your own bricks on a printer made of LEGO?

29 thoughts on “Laser Cut LEGO In MDF

        1. He’s actually probably the best next to Jenny. Ask any 3 year old it’s “Legos.” Language is a flowing river always changing course, rising and falling, people that insist on LEGO should also insist on going back to proto indo-european as that is how words ought to be pronounced.

          Point being it makes sense to evolve a language towards more precision/conciseness, Legos is more telling than LEGO as one is a description of many plastic blocks and the other is a company.

          TLDR: 3 year olds are smarter and less stuck in the mud than you.

        2. First Benchoff rising to the bait, now trolling the comments himself. Guy needs a break, man, or a hobby, a holiday, or something.

          The plural of “Lego” isn’t “Legos”, it’s a mass noun like “sugar”. One is “a brick of Lego” like “a grain of sugar”, but the thing itself is just “Lego”. It’s only Americans who say “Legos”, but let’s let our language be controlled by an ignorant people who don’t even realise they’re not the whole world.

          1. “Legos” is as appropriate a word for use as “aluminium” is. Neither was where the word started, but became in common use by different branches of the English language. Claiming others are ignorant and don’t realize their way of speaking English isn’ the whole world, while explicitly indicating that -you- don’t realize your version of English isn’t the entire world… well, that’s just funny.

          2. “Sugars” is definitely in active use within scientific (and other) English. The context would be something like, “multiple sugars are used as building blocks to synthesize [x]”, “Two sugars are consumed for each [y] produced”, etc. A non-science context would be something like, “I’d like two sugars in my coffee”.

            In each case it is a non-specific (but definable) pluralization, while the mass noun (sugar) would be for a non-specific (but non-definable) pluralization.

  1. That’s a so-so idea. MDF is built in layers, so, you will be able to snap blocks, but when you try to remove them, they will rip apart the studs.
    Might be reinforced with some acrylic lacquer or resin, but still, not the best material to do such things.

    1. I heartily endorse this type of project, but I have some observations/suggestions.

      A lot of cheap whiteboard is made from melamine, which is toxic in chronic exposure (and more so if inhaled or ingested). This is fine for our crowd, but not for kids who might rip off and swallow the buttons or chew the bricks.

      As others have noted, MDF is layered and won’t hold together well. It’s also not waterproof, and can wick up moisture from the air and support mold growth.

      On a technical level, it’s not terribly difficult to generate DXF files from a program – I know there’s a plugin for perl that does most of the heavy lifting, probably Python as well. The design might benefit from having the laser first cut the outlines of the holes, then raster engrave the profiles. The cut would make the tabs highly accurate against the raster operation.

      Legos are very well made, and with high tolerance. Most lasers have a kerf based on the spot size that has to be accounted for when cutting highly accurate parts. I have a description of this on one of my projects (link below), and my particular solution. The project might benefit from some type of “test cut panel” as described in the link, so that people could quickly and easily zero in on the correct settings for their laser and stock.

      This is a really good start on something useful, but it looks like it would benefit from some improvement.

  2. Mein runt is after me to crank out LEGO parts on the CNC. Shouldn’t be too difficult, but I think he’s got mass production on his mind.

    Um, NO! Custom parts for items we want to build with LEGO, but it’s not a brick factory.

  3. Lego bricks indeed last nearly forever. The oldest bricks in my box are from the 1950’s and, with a few exceptions, they have not lost any “snappiness”. Yes, they are expensive but all the knock-off bricks just don’t have the quality.

  4. Getting a laser cutter to engrave to a consistent depth is a nightmare. You can see in the picture how it’s curved at the base of each of the studs, and it’s even worse with acrylic.

    1. In the 1980s, Lego Technic had motors with a 2-pin connector that was also a 2×1 Lego brick. They might still make them, I dunno. IIRC there was something terminal-blocky about them, there was a screw in there somewhere. The pins fit into holes that were in each plug, and the holes were Lego stud size. Pretty neat actually.

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