A Linux computer in an unmodified mint tin.
A Raspberry Pi Zero 2 W, 53 keys, a 2.8 inch screen and a battery good for an estimated 9 to 11 hours idle or 5 to 7 hours of work. Open the lid and it boots; close it and it shuts down.
Status: rev C2 boards designed and checked in CAD. First prototype next. The board, CAD and BOM files will be public on GitHub.
The DIY kit, laid out
Planned contents, not final, drawn to scale with each other. The fiddly parts come done: every surface-mount part is already on the main board. The dashed outline is the one part you bring: your own Pi Zero 2 W. This is a US order with the printed parts included. Kits shipped abroad leave out the cell, and if you untick “Include printed parts” at checkout, the carrier, lid plug, keycap mat, lid stop parts and stop gauges are yours to print.
Tap a part to find it in the parts list.
Parts list, DIY kit (planned)
| Qty | Part | Notes |
|---|---|---|
| 1 | Blank tin | Hinged, checked to fit. No branding. |
| 1 | Main board | All 47 underside surface-mount parts placed by machine, and the NORMAL/SERVICE slide switch fitted. You solder the Pi's header and the socket it plugs into, the pogo and J4 sockets, the battery leads and two thin USB wires from the Pi's test pads. The Pi's header goes in from the Pi's back and is soldered on the component side, because the Pi sits upside down under the board. |
| 1 each | Display and lid flex | 2.8 in IPS panel, and the flex that carries it over the hinge: a plain cable with no parts on it. You lap-solder the panel's 18-pad tail onto the flex. |
| 1 | Keycap mat | Printed TPU, 53 keys. One of the printed parts. |
| 60 | Metal domes | 6 mm, 180 gf. 53 on a carrier sheet plus 7 spares. |
| 1 set | Printed carrier and lid plug | PA12, with its two M2 heat-set inserts fitted. Holds the Pi, the cell and the board. The lid stop's anchor and cleat and the two stop gauges come with it. Untick "Include printed parts" at checkout to print these and the mat yourself; the two inserts then come loose in the bag. |
| 1 | 704080 LiPo cell | US orders only. 7 x 40 x 80 mm, protected, with leads. 3,000 mAh listed, about 2,600 mAh expected. Kits shipped abroad leave it out, and you buy a 704080 locally. |
| You | Raspberry Pi Zero 2 W | Not included. Any Pi Zero 2 W works. |
| 1 | microSD card | 32 GB, A1 class. |
| 1 | Magnetic cable | 6-pin magnetic plug to USB-C. Charges, and carries USB and serial. |
| 1 | Hardware bag | Two M2 screws and a nylon washer, the lid magnet, the closure magnets (4 bars, 20 discs), thermal pad, tapes, lid-stop line, enamelled wire for the USB pair, two-part epoxy and flexible glue. |
Everything fits in 20.8 mm
The Pi sits upside down on the tin floor, which is its heat sink. The battery rests on it, then the main board, the metal domes and the keycap mat. With the lid shut, the screen clears the keycaps by 1.16 mm.
Section through the closed tin
Specifications
| Computer | Raspberry Pi Zero 2 W, quad-core, 512 MB |
|---|---|
| Screen | 2.8 in IPS, 320 × 240, in the lid |
| Keyboard | 53 metal domes under a printed keycap mat, Fn and Sym layers (planned in software) |
| Battery | 704080 LiPo, 3,000 mAh listed, about 2,600 mAh expected, with a fuel gauge |
| Runtime | 9 to 11 h idle with Wi-Fi, 5 to 7 h working, estimated from the power budget |
| Power | Open the lid to boot, close it to shut down |
| Port | 6-pin magnetic: charging, USB network, serial, USB drive |
| Expansion | 14-pin header: I2C, SPI, UART, 3 GPIO, switched 5 V |
| Closed size | 94.5 × 59.8 × 20.8 mm |
| Weight | About 140 g, estimated |
| Software | Raspberry Pi OS Lite, 64-bit |
Two ways to get one
Proposed prices. Nothing is decided yet. $89 is the US kit with the cell and the printed parts.
| Proposed, not final | DIY kit$89US, Pi not included | Assembled$179Pi included |
|---|---|---|
| You bring | Your own Pi Zero 2 W. The microSD card is in the kit, and so is the cell on US orders. Outside the US, you also buy a 704080 cell locally. The enamelled wire, epoxy and glue the build needs are in the kit | Nothing |
| You solder | The Pi's header (in from the Pi's back, since the Pi sits upside down) and its socket, the pogo and J4 sockets, the battery leads, two USB wires and the display's tail | Nothing |
| Comes done | Main board with every surface-mount part, the tin, and the printed parts with their heat-set inserts already fitted | Built, flashed and tested |
| Your choice | “Include printed parts” is ticked by default. Untick it and you print the carrier, lid plug, keycap mat, lid stop parts and gauges yourself from the files, once they are public, for $10 less. The two heat-set inserts then come loose in the bag | None |
| Build time | To be measured on the first prototype | None |
| Ships | US orders include the cell. Abroad, the kit ships without it, since a loose lithium cell can’t go by international mail, and it costs $12 less | US only at first |
There’s no checkout yet. The printed-parts choice will be a tick box on the checkout page when kits open. A bare board set and a kit with the Pi included might follow, once there is a steady supply of Pis.
Built in the open
The board files, the CAD exports and the bill of materials will be public under the CERN Open Hardware Licence, strongly reciprocal, version 2 (CERN-OHL-S-2.0), and so will the software. Build one from the files once they are public, or buy a kit and skip ordering from 8 vendors, plus a few parts from any store.
The repository
mintydeck/ ├─ hardware/ │ ├─ pcb/ main board and lid flex, rev C2 │ │ └─ jlc/ BOM and placement │ ├─ mechanical/ │ │ ├─ print/ STL, ready to print │ │ ├─ step/ STEP, every part │ │ ├─ reference/ tin, board, display │ │ └─ data/ keys, stop, magnets │ └─ MintyDeck-order-BOM.xlsx bill of materials ├─ mints/ add-on boards for J4 ├─ software/ desktop app and recipes └─ LICENSE CERN-OHL-S-2.0
The repository is private for now and goes public on GitHub at launch.
Build log
- Rev A2The whole stack redrawn against caliper measurements of a real tin.
- Rev BMain board laid out in KiCad and routed track by track, no autorouter.
- Rev CEvery surface-mount part moved underneath, so one machine pass places all 42.
- Rev C2The display's tail now solders straight onto the flex. One board fewer.
- Lid stopA braided-line stop holds the lid at 93 degrees.
- J4 and magnetsThe J4 expansion header became a 14-pin socket only 3.4 mm tall, behind a hot-swap I2C buffer, and four pairs of magnets now hold the lid shut. 45 parts placed by machine.
- Plain flexThe lid flex lost its two capacitors and is now just a cable. They moved onto the main board beside its connector, so the machine places all 47 parts.
- First mintsTemplates and seven add-on board designs for J4, each with the ID chip that tells the deck what it is.
- First prototypeOrder the boards, build one, photograph it, film it.
Questions
Will it fit my tin?
It's built for the classic hinged mint tin, the size Altoids come in, measured with calipers at 94.5 × 59.8 × 20.8 mm closed. Blank tins vary by a millimetre or two, so the kits will include a tin that's been checked to fit.
How hard is the DIY kit?
Every surface-mount part comes fitted. You do the through-hole and wire work: the Pi's header and the 2 × 12 socket it plugs into, the pogo and J4 sockets, the battery leads, two thin USB wires from the Pi's test pads, and the display's tail. The Pi's header goes on the unusual way round: in from the back of the Pi and soldered on the component side, because the Pi sits component side down under the board. That tail is the hardest joint: 18 pads at 0.8 mm pitch, lap-soldered onto the flex with a fine tip. The build guide will walk through each step.
What does it run?
Raspberry Pi OS Lite, 64-bit. The keyboard is a normal Linux keyboard to the kernel, and the Fn and Sym layers will come from keyd, set up by the on-deck software I still have to write. If it runs in a terminal on a Pi Zero 2 W, it runs here.
Where will it ship?
The US first, with the cell in the kit. A loose lithium cell can't go by international mail, so DIY kits shipped abroad leave it out and cost $12 less (a proposed price, like the others). You buy a 704080 cell locally: 7 × 40 × 80 mm, 1S, protected, with leads. The assembled unit is US only at first.
Can I print the plastic parts myself?
Yes. The kit will have an “Include printed parts” option at checkout, ticked by default. Ticked, you get the PA12 carrier with its two M2 heat-set inserts already fitted, the lid plug, the TPU keycap mat, the lid stop's anchor and cleat, and the two stop gauges. Untick it and the kit costs $10 less (also proposed), and you print those parts from the files in hardware/mechanical/print/. The two inserts come loose in the bag, for you to set into your carrier.
When?
No date yet. The rev C2 boards are designed and checked against the 3D model. The first prototype comes next, then a small batch. The list hears first.
One email when kits open
No newsletter. Tell me which version you'd buy; it decides how many of each I make.