How to securely store Bitcoin and other Crypto-Currencies
After following Bitcoin and Cryptocurrencies for a few years, one thing became very obvious to me. The number one risk when investing is not hacking or security flaws, it’s user error. It’s so incredibly easy to lose access to your private keys. The hacking risk is still to be taken seriously and the measures describe here help mitigate that risk as well.
This page is meant to list conventional best practices on hold to hold crypto-currency in an secure manner. I’m open to feedback on this, please email firstname.lastname@example.org. Full disclaimer: I have an affiliate link for Trezor below.
Here is one way to stamp your recovery seed onto metal plates. Please scroll down to see alternative methods.
These steel plates are designed to have a BIP39 24 (or 25) word passphrase stamped onto them, using a letter punch kit, to allow recovery of crypto currency private keys. Whether for use with a software wallet, or a hardware wallet like the Trezor, having the recovery passphrase stamped onto corrosion-proof and fire-proof metal plates minimizes the risk of loss of private keys. You can see letter punching in action on this video, although with our plates we will punch the full BIP39 words using letters, not numbers: ColdTI Punching Video.
The stainless steel plates can be ordered from Lasergist using instructions below. They are laser-cut from 3mm stainless steel or any other thickness available on lasergist. Technically, the middle plate is the only one required and has laser markings indicating passphrase word ordering. By having additional plates cut, the passphrase can be hidden from sight and zipties can be added to prevent tampering. It also increases the weight of the whole assembly (close to 1kg with 3x 3mm plates) which helps prevent accidental misplacement.
The titanium plates were ordered as a custom-made item from Calti Wallets using the same designs available below, I believe he plans on making more of those available.
Titanium Grade 2, 2mm
These plates should resist a 1600 °C / 3000 °F house fire. They are much harder to punch than the stainless steel ones, so I recommend a carbide tip engraver (see additional hardware below).
Stainless Steel (316L), 3mm
Below is a description of the Adobe Illustrator files used to place the order from Lasergist.
If you just want the passphrase plate with the 25 locations to stamp words, the two files below are all you need.
If you want the front plate with your name on it, you need to submit these two as well (modify frontplate_laser.ai to include whatever text you want)
This plate is just an empty plate with the cutouts for screws, but no laser engravings:
And finally this files contains all above designs on different layers, which may be useful if you wish to customize the design further.
Head over to lasergist, start a new design
You will want to submit numbers_plate_shape.ai and numbers_plate_laser.ai, with the following options:
You may change the thickness and material used, and uncheck sandblasting if you wish (selecting different options may change the price). But with the above settings, the price for that plate comes out to USD $85.53.
Then depending on whether you want the other plates, repeat the process for frontplate_shape.ai, frontplate_laser.ai (of course you’ll want to modify them first before submitting). With similar settings to above, it came out to USD $59.57
The backplate, backplate.ai doesn’t require any laser engraving and cost $49.10 with the following settings:
If you ordered seperate plates and want to fasten them together, you may order the following screws:
The 12mm screws are sufficient to hold 3x 3mm plates. If you have less plates, less thick, or more (perhaps you have different seeds for different coins), then you’ll need to get different screws.
Then additionally, you’ll want the letter punch kit. I ordered this one from ebay: letter punch kit. The design on the plate is designed to accomodate words at least 8 characters long, with each letter 4mm x 4mm.
If stamping proves difficult (I found it to be extremely difficult on the titanium grade 2 plates), you could use an electric Carbide Tip engraver such as this one Carbide Tip engraver
Finally, you can order zip ties to prevent tampering with the seed.
Also if you like this design, feel free to send me a tip !
cryptosteel.com This is a reusable steel “container” which holds the first 4 letters of each of your BIP39 recovery seed words. It sounds like a great product, many people like it. The thing that worries me is that the words could be accidentally scrambled, which is impossible to do if the recovery seed has been stamped onto a plate of metal. Also, only including the first 4 letters, while sufficient according to the BIP39 spec (since the first 4 letters uniquely identifies the BIP39 word), seems like you would lose on some of the inherent “error correction” of having the full word written down (which would be more resilient against a single missing letter in my opinion).
billfold.com Similar to the Cryptosteel, but with laser printer letters, made from 316 steel, and cheaper.
Blockplate Stainless steel plate which uses an innovative method to store the recovery seed onto a grid, without needing a letter punch kit, only a single basic punch.
coldti.com Kickstarter for titanium plates onto which you stamp the BIP39 word numeric identifier. Doesn’t look like they reached their Kickstarter funding goal, but they are planning on selling on Amazon. They have cool videos showing the punching or engraving technique
Order a simple stainless steel or titanium plate from Ebay and punch it. It may be difficult to find the right size, but this is the cheapest option of them all.
You could just write your seed on a piece of paper, but a piece of paper is easy to misplace, accidentally throw away, the ink may fade, flood and fire are a concern. Hard to protect against tampering.
glacierprotocol.org , Glacier protocol description This is a method for ultra-secure storage of bitcoin, potentially more secure than hardware wallets. But also much more complex and costly. I haven’t attempted that method. It requires significant more investment in money and time.