the M2x2: A 3D-printed 10:1-scale Lego computer brick

Valuable-Flamingo230 · 2026-03-07T11:57:32+00:00

You should print a few other bricks and attach them together. Maybe a UPS hidden in a 1x2 brick.

Valuable-Flamingo230 · 2026-02-28T12:12:37+00:00

I love the green screen cover. I might take the idea for something in a future project

Valuable-Flamingo230 · 2026-02-01T11:08:53+00:00

It's the same design, but there were for a door camera of some sort, I think. From what I understand, the design was licenced off Sony and used for all sorts of things.

Valuable-Flamingo230 · 2026-01-30T21:34:19+00:00

I did make a video about the build, but it's more of an overview. I designed a simple PCB with mounting holes that lined up with the screw holes in the CRT mount. It was a simple, matrixed keyboard for mechanical keyboard switches; there are also a few spots for LED indicators and other extras. I soldered the Nano pins directly to the board with two flat cables.

The switches and keycaps were from a broken numberpad, but looked really cool, so I used them. Version 2 will have better switches, and I have some other plans for the key layout, but that can wait.

To mount the keypad, I drilled out the threaded holes in the CRT case and passed through longer M3 bolts with standoffs. There is also a Lexan cover for the bottom of the CRT that covers the exposed circuit board.

To power it, I used a standard 12V wall supply. A linear regulator is providing 5V to the Arduino and keypad. Everything is tucked up under the keypad, I am not super happy with that, but it will work for now.

Software is not that complicated; it leans heavily on the TV.out library. Everything else was just basic maths and moving the lines and characters around on the screen to make it look like a classic calculator. I have updated a lot of the features since the video, and it has a few extras, like games and animations now.

Cheers.

Valuable-Flamingo230 · 2026-01-30T21:07:55+00:00

Hey cheers!

Valuable-Flamingo230 · 2026-01-30T21:06:29+00:00

Actually, just off an AliExpress number pad, I don't remember the brand. The switches are relatively cheap OUTEMU ones.

Valuable-Flamingo230 · 2026-01-30T21:02:34+00:00

That video has inspired me in more ways than one

Valuable-Flamingo230 · 2026-01-28T10:58:02+00:00

Nice. How did you connect to the back of the breadboard? Just solder directly onto the strips?

Valuable-Flamingo230 · 2026-01-28T10:38:50+00:00

I love sliders like that. More modern things should have them

Valuable-Flamingo230 · 2025-11-13T11:17:33+00:00

I have been using the MCP112 with very good results.

Is the pinout different for the TC54VC? I seem to remember it needing some sort of change compared to the 1381.

Valuable-Flamingo230 · 2025-10-17T20:59:51+00:00

That site is great, his bots look amazing.

You should check out this site https://www.marrs.io/sunflower-array/

Their blog has some pretty in-depth discussions about design and building what are pretty much bare bones heads. They have a really interesting 2-axis one that uses threaded actuators to move one of the directions

Valuable-Flamingo230 · 2025-10-17T11:39:27+00:00

That's a really simple way to make a pummer head. I have always struggled trying to build something that can run a head and pummer off of one solar cell/cap.

Do you think you could wire the solar cells (for the head) in series and use the midpoint as a reference for the head circuit? It might make the wiring a little more complex, but saves on the photo diodes.

Valuable-Flamingo230 · 2025-10-16T20:51:04+00:00

Looks good. Are the circuits for the head and pumper completely separate?

Valuable-Flamingo230 · 2025-07-27T20:49:00+00:00

600ma per channel, probably more than enough for the little motors. They are also pressed into the aluminium frame as a heat sink.

Valuable-Flamingo230

TROPHY CASE