The DEC Mini is made of the same stuff dreams are made, so it cannot be bought. You’ll have to build your own with patience and love. A lot more patience than love.

Because the DEC Mini is a full-size computer, there are many parts to be 3D-printed. The bigger parts have been designed to be printed in pieces and then glued together. This allows them to be printed in small 3D-printers, and if a print fails, only that piece must be printed again.

What you’ll need

  • A 3D-printer with a 220x200mm bed or more. The Creality Ender31, the Artillery Genius1 and other similar printers can print it.

  • 3D-printing filament spools: 1 black spool for the display parts, the backplates and other inner pieces, and 3 white spools for the casing parts 2. Or another color combination you like. I’ve used this eSUN Pla+ Pro and I loved it, specially because the white is truly opaque.

  • Glue for plastics, since some of the printed parts must be glued together. Glue with filling capabilities like 2-part epoxy-based glue is recommended. Test your glue with the provided small test parts.

  • A size-compatible keyboard like the DREVO Calibur V2 1. Other similar keyboards might be also compatible, but haven’t been tested. Check this guide on finding compatible keyboards.

  • Stripping out the parts of a 10" inch HDMI 4:3 monitor like the Eyoyo 10" inch IPS HDMI 4:3 display is the recommended option, since you’ll be able to forget about the audio amplifier and connect the speakers straight into the monitor board. By doing so, you’ll also avoid annoying and very noticeable noise interferences which usually happen when using cheap amplifier boards. The integrated audio amplifier from a display like the Eyoyo is well isolated electrically and takes the audio signal from the HDMI cable, which saves you one additional cable. The HDMI 10" LCD Screen from Pimoroni3 will also fit nicely, but it doesn’t comes with audio output.

  • A Raspberry Pi 41, or any other SOC board of your liking, since there is plenty of space inside. The LattePanda Alpha3 is strongly recommended. Check out the Backplate parts section, as some other builders might’ve contributed backplates for the SOC you like, or you can customize your own backplate.

  • An 80mm fan. If you’re using a motherboard running at 5 volt like the Raspberry Pi, this one is really recommended1. This is the 12 volt version1 if you’re using a 12 volt-based system with a motherboard like the LattePanda.

  • A rocker switch that fits in a 13x20mm hole, like this one 1

  • Two 4 ohm 6.5cm speakers like these from Pimoroni 3. The screw holes have been placed for this specific speakers, but other speakers shouldn’t be difficult to fit or glue as long as they’re 6.5cm in diameter.

  • An audio amplifier board like this one1, or any other you like, as long as it’s stereo, has a rotary volume knob to fit in the power backplate and is powered with 5 volts 4. Using the integrated amplifier in a stripped out monitor is recommended over this option, see above.

  • A 5 volt power supply 4 like this one1. Be sure it’s at least 5 amp, and that it accepts the right mains voltage spec of your country. If you’re fitting a LattePanda Alpha or Delta motherboard, or any other 12 volt based motherboard, you can use this power supply1

  • If you’re going for the full retro-floppy experience, a 3½ disk drive and one of this adapters from AliExpress 3.

  • M3 screw brass inserts like this ones1, and also a set of M3 screws like this1 should be enough.

  • Some JST connectors like these1 will help you make everything detachable, so you can open your DEC Mini easily.

The usual soldering iron and accessories, plus some AWG 20 cable to wire the motherboard, and some AWG 12 cable to wire the power socket to the power supply.

So, you’re ready to print?

Get the 3D files →

  1. Sponsored link ↩︎

  2. It took me 4 spools of filament in total after some wasted prints. You might only need 2 white spools instead of 3 if you’re good at 3D-Printing and specially if you have a filament run-out sensor that allows you to make the most out of each spool. ↩︎

  3. Non-sponsored link 😕 ↩︎

  4. 5 volts if you’re using a Raspberry Pi motherboard or another 5V motherboard. Be sure to use the voltage that fits your motherboard of choice. ↩︎