What is it?

This is a cheap DIY metal seed phrase/recovery backup.

When you setup a non-custodial crypto wallet, you are asked to securely backup a series of words (typically 24): This is your recovery seed. With this seed you can recover your funds even if your wallet gets physically destroyed.

At some point you will be asked to write down your seed on a piece of paper (sometimes they even include the paper). The problem is that paper isn’t the most secure way to keep your backup seeds in the long run.

This is why metal backup seed are a thing. They keep your backup safe even in case of a fire or a flood or any natural disaster.

Why did you make it?

This year was absolutely crazy for cryptocurrency and if you are reading this there is a good chance that you are looking for a solution to secure your recovery seed without spending all your money on an overpriced steel wallet. You’ve probably already seen those, they can cost up to 249€. This is just ridiculous.

One day I came across this website made by Jameson Lopp where he put to the test the most populars metal seed storage solutions.

Turns out that the most expensive ones weren’t always the most robust. I was quite surprised to see the super popular Cryptosteel failed the tests.

The SAFU Ninja was the one that surprised me the most. It was a DIY solution that outperformed many commercial steel backup for a fraction of the cost.

Also this nice little jig can help you aligning the punches to make sure your seed is readable and pretty.

Also there is this really talented guy that machined a capsule with his metal lathe for his version of the SAFU Ninja.

But unfortunately not everyone have a metal workshop in his garage or easy access to a 3D printer...

So this is why I’ve put together this kit!

What makes it special?

It's a fraction of the cost of all commercially available products. Seriously.

IMPORTANT

You will need some tools that aren't included (they are stupidly heavy and the shipping already cost more that the product itself)

Tools needed:

• Punch set with 3mm letter high (the width of the punches need to be exactly 6mm otherwise they won't work with the jig) I recommend using this set from Amazon (it’s the one that I used and it’s not crazy expensive)
• A thumb detector (a hammer) : there is a good chance that you already have one at home.
• An anvil (or any other hard flat surface should work)
• Some tape
• A 3mm Allen / hexagonal key wrench for the bolt (if you bought some IKEA furnitures you already have one of this somewhere)
• A 8mm wrench

What is included?

• 1 stainless steel (304) capsule
• 24 M5 stainless steel (304) washers (+ 2 extra washers: 1 to practice your swing skills and another one in case of an oopsy)
• 1 M5x35mm flat head Allen / hexagonal socket stainless steel (304) screws
• 1 M5 stainless steel (304) cap nut
• 2 spare O-rings

Optional

• I can add a 3D printed jig if you want, just make sure to select the option when making your order.
• 2 tamper-proof sticker so you can check if someone tried take a look at your seed.

Tips

• You don’t need excessive force when stamping the washer. Doing so will likely end up in a warped washer.

• Thin letters / numbers like L / I / J / T / 1 / 7 need less pressure to left a good trace. For instance if you use the same amount of force while stamping the letters « H » and « L » you will find that the « L » will go deeper than the « H ». Use the extra included washer to practice your swing ;)

• Use masking tape under the washer to keep it in place.

• I always get the « D » backwards no matter what (T_T) . Maybe you’ll succeed where I failed.