Seedsigner

Make your own hardware wallet for $50 using off the shelf components!

This is a fully functional, airgapped hardware wallet that one can use to make bitcoin transactions, both single sig and multi-sig.


Part 1: Parts and Cost

You will need:

1. Raspberry Pi Zero (version 1.3)

2. WaveShare 1.3 inch LCD hat with 240×240 pixel display

3. Pi Zero compatible camera module

4. MicroSD Card with at least 4GB capacity

My parts and cost:

Total, with case: $80

Total, no case: $45

If you can solder, it’s under $40.


Part 2: Assembly

2a: Adding GPIO Pins (Solderless Option)

The Hammer Kit

Kit Assembled

Clamping it Down

Assembly Continued

Raspi, Camera, Screen

Attach Camera

Set into Case

Add Screen

Build Complete


Part 3: Basic Use

  • Create Seed from Dice

  • Create seed from random image entropy (interesting but untested)

  • Make your own QR codes and scan later

  • Add passphrases and do checksums (verify last word)

  • Robust single sig and multi sig with PSBTs and QRs

  • Works woth Specter, Sparrow, and BlueWallet

Part 4: Pros/Cons


Cons:

  • Issues with orange pill joystick

  • Sourcing issues for people who need it most

  • Boot up time (30-45 seconds)

  • No persistent memory

Pros:

  • Cheap and accessible

  • Simple and intuitive airgapped multisig, psbts, and seed generation

  • Constraints of hardware required lots of cool innovations: QR code fill in, coldcard now supports QR codes (directly influenced other manufacturer)

  • No persistent memory