Securing Your Seed Phrase with Washers

[HideYourKeys]

The only point I do not understand in your Jig is how the washer is fixed in the correct position and what prevents it from moving after each letter is stamped.

From Stamping JIg Instructions Manual:

Once the washer is inserted, rotate the BitJig to the lock position, securing it firmly, note that the washer holder inside the base moves down

I assume there's some thread inside to "clamp" the washer in place, but I can't envision how that works since the washer fits through the hole of the base that moves down.

The only point I do not understand in your Jig is how the washer is fixed in the correct position and what prevents it from moving after each letter is stamped.

From Stamping JIg Instructions Manual:

Once the washer is inserted, rotate the BitJig to the lock position, securing it firmly, note that the washer holder inside the base moves down

I assume there's some thread inside to "clamp" the washer in place, but I can't envision how that works since the washer fits through the hole of the base that moves down.

Exactly.
Still, I don't understand how it is clamped, avoiding unwarranted movements.
I don't know if it is an industrial secret,  but it would be nice to know more.
I guess this is one of the most critical aspects for a good jig.

As LoyceV said, there is a threaded piece inside, which allows you to secure the washer. That piece has an inner diameter, which is slightly smaller than the washer's diameter, so it locks the washer when the jig is fully rotated to the lock position. In order to introduce the washer (which has a larger diameter as we already know), it is possible because this threaded piece which "clamps" the washer, has several lateral "gaps" which provide a slightly larger diameter than the washer. Therefore it can be introduced if the washer is rotated vertically and introduced through the gaps when the jig is at the fully "unlocked" position (pictures on pages 4-5 of the manual might help you visualize it). Tolerances are quite tight though, there were a few iterations before it was good enough...

We got a review last week from a substacker who wanted to test it, you can check the 4th image, which shows it better (it is in Spanish though, but you can translate it)

https://cryptosecurity.substack.com/p/hide-your-keys

[n0nce]

[...]
Looking forward to your thoughts and ideas!

Looks really good, you did a great job with the modeling and I love your innovation that removes the need of an anvil!

I'd like to print the STL and try it for myself, to be honest, since I made my own open-source, customizable steel washer backup jig back in 2021:
n0nce's Steel Washer Backup jig (customisable)

It is much simpler than what you made, but people can get an STL for any washer size (metric, imperial, any size, any thickness).

[HideYourKeys]

[...]
Looking forward to your thoughts and ideas!

Looks really good, you did a great job with the modeling and I love your innovation that removes the need of an anvil!

I'd like to print the STL and try it for myself, to be honest, since I made my own open-source, customizable steel washer backup jig back in 2021:
n0nce's Steel Washer Backup jig (customisable)

It is much simpler than what you made, but people can get an STL for any washer size (metric, imperial, any size, any thickness).

Thanks for your feedback! I would love to give you the .STL files so you can try it, but that would be a risk as the files might spread all over the internet. Let me explain my thoughts:

The target is to get enough visibility, scale the project and if this jig "gets known" after some time, sell the mechanized one in CNC at a reasonable cost, and then release the .STL files for the basic version (therefore the official one in metal could be purchased, and the one in plastic could be made with a 3D printer + buying a steel disc a certain diameter and thickness, which are quite affordable). This would be a similar approach with blockstream Jade for instance, which is a HW that can be purchased officially, but the firmware is OS and you can flash it on many ESP32 boards.

In the meantime... if you live in Europe I can send one to you for free, so you can test it    (you do not have to give a real name, and it could be sent to an InPost locker, so no real address is needed). At the bottom of the webpage you can see the TG, mail, etc... to contact ( https://hideyourkeys.io/ ), or send me a DM here

[HideYourKeys]

I made a video, so the curious ones can check the results, and the whole process:

https://www.youtube.com/watch?v=SWVvvpQr304

Notice that I only struck each letter once, and didn't apply much force, for other washers I have tested the letters and numbers are engraved at a deeper level (if you hit them harder, of course)

[fillippone]

I made a video, so the curious ones can check the results, and the whole process:

https://www.youtube.com/watch?v=SWVvvpQr304

Notice that I only struck each letter once, and didn't apply much force, for other washers I have tested the letters and numbers are engraved at a deeper level (if you hit them harder, of course)

Wow very nice.
That is a serious jig.
I like the mechanism that holds the washer in place. I had to apply a scotch on the bottom of the jig, but you improved this by far, as the washers apparently aren't moving.
Well done.

[apogio]

Notice that I only struck each letter once, and didn't apply much force, for other washers I have tested the letters and numbers are engraved at a deeper level (if you hit them harder, of course)

Very good result! Congrats!
I liked the fact that you didn't have to use an anvil.

[satscraper]

Still I would advocate washers holding binary code of  numerical order of relevant word in BIP39 list. Such washer would look like this.

(a washer containing the word "sausage" -  decimal  numerical order is  1534, in binary representation - 10111111110. The numbers near the edge of the washer are placed in the figure only for guidance in the position of the bits. The vertical is the marking reference.)

The benefits - such washers are easy to stamp ( as the single  center punch is needed instead of multiple bits with letters), and their purpose are not so obvious for others.

[LoyceV]

The benefits - such washers are easy to stamp ( as the single  center punch is needed instead of multiple bits with letters), and their purpose are not so obvious for others.

The drawback: you lose the "error correction" you get when using words. A binary "typo" won't be very obvious to detect.

[satscraper]

The benefits - such washers are easy to stamp ( as the single  center punch is needed instead of multiple bits with letters), and their purpose are not so obvious for others.

The drawback: you lose the "error correction" you get when using words.

Nope, the order of washers  (i.e the order of words) can be marked by daps on washers' ribs. BIP 39 "error correction" is the responsibility of  last word, thus such function is preserved as long as  the relevant washer is  on the bolt .

A binary "typo" won't be very obvious to detect.

 I have such washers, they are very easy to make without any "typo" as well as to decrypt. But sure, this method is not  for clumsy hands, i.e not for those, who can make "typo" at very simple doing.

Check twice!

[LoyceV]

Nope, the order of washers  (i.e the order of words) can be marked by daps on washers' ribs. BIP 39 "error correction" is the responsibility of  last word, thus such function is preserved as long as  the relevant washer is  on the bolt .

I meant the error correction you get with words: if you misspell abandon, it's still pretty clear you mean abandon. But if you misspell 10111111110, there's no way of knowing other than carefully checking.

this method is not  for clumsy hands, i.e not for those, who can make "typo" at very simple doing.

I've seen topics from people who lost their crypto because they made multiple mistakes writing down private keys. But you're right: it can be done. At least try to recover your seed from scratch before funding (which is good practice to do with any backup anyway).

[fillippone]

Still I would advocate washers holding binary code of  numerical order of relevant word in BIP39 list. Such washer would look like this.

(a washer containing the word "sausage" -  decimal  numerical order is  1534, in binary representation - 10111111110. The numbers near the edge of the washer are placed in the figure only for guidance in the position of the bits. The vertical is the marking reference.)

The benefits - such washers are easy to stamp ( as the single  center punch is needed instead of multiple bits with letters), and their purpose are not so obvious for others.

Don’t be your own enemy.
One key benefit of such solution is the fact they can be easily interpreted by others.
KISS principle is the reason why we are stamping washers in the first place.
Stamping binary only raises the bar for securing the generational wealth.
Just remember this is not for short term self custody, but for long term inheritance. The person receiving the washers must be able to understand what they are.

[satscraper]

Don’t be your own enemy.

I will not be. I trust my own gut.   I take to binary like a duck to water.

One key benefit of such solution is the fact they can be easily interpreted by others.
 

In my view this is disadvantage rather than benefit.  

Just remember this is not for short term self custody, but for long term inheritance. The person receiving the washers must be able to understand what they are.

Sure, I don't think that  mentally slow generation is what is going to happen next  

[fillippone]

In my view this is disadvantage rather than benefit.  

Part of why I stamped my washers is that if something happens to me, my relevant one(s) can retrieve my precious sats.
Of course, this involves some trust.
But I sleep better thinking that the precious satoshis aren't going to be gifted to all of you as added disinflation.
Also, I sleep better knowing that my trust doesn't steal the funds from me (yet, I do a yearly on-chain and off-chain check).
Sorry if I am selfish toward my loved ones.