This is cool because, if you don't know, a seed phrase actually isn't enough to recover your Bitcoin.
Seriously. Go download a wallet that wasn't the wallet you created the original wallet from and try to backup with it.
See, there's a lot of missing information in a seed phrase. The script type and the derivation path are your main concerns for a single sig.
For a multi-sig, you also have to have ALL xpubs for ALL seeds in the multi-sig.
This device punches all of that information into steel for you. That's why its cool.
And if you're ignoring this and rocking single sig, go you. Just remember what wallet and version you generated your seed with.
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That is definitely scary and kind of a misconception in the community
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If all that you're missing is the script type, there's few enough of them to just guess.
If you're missing the derivation path, you can either remember what wallet you generated from or brute force the defaults list: https://walletsrecovery.org/
But multi-sig is where it gets tricky because the xpubs can't spend your funds, but they can dox your stack. So you can make it more available (upload it to a cloud storage provider) with the risk being that the company you upload it to, or a hacker who may or may not leak the info, will dox all your Bitcoin in all your addresses (knowledge that the addresses all belong to one person), but they still can't spend from it.
You can trade off an xpub's confidentiality for more availability (the security triad)
Its just neat to be able to have it all stamped into a plate. Then, even if you didn't know you needed all that other stuff, you still have it.
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script type, derivation path, xpubs? I had no idea
I assumed the 12 or 24 words were sufficient
I believe you but I'm going to try to 'recover' my wallet
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613 sats \ 1 reply \ @zklsbn 15 Jul
deleted by author
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Thanks for answering! Very clear!
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13 sats \ 4 replies \ @Fabs 14 Jul
I'm pretty damn sure that if I'd go through the hassle of recovering my wallet with words + phrase, that I'd get exactly what I have now.
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Go download a wallet that wasn't the wallet you created the original wallet from and try to backup with it.
Go try it. Find your wallet in this list: https://walletsrecovery.org/
Then, pick another wallet that doesn't have the same derivation path. I'm not saying do it with your main stack, or even a wallet that has Bitcoin in it. Just try it with a wallet that had Bitcoin in it and you'll find that you can't get your wallet history or even the same Bitcoin addresses to show up.
Not really an argument to be had. Its a technical reality.
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313 sats \ 2 replies \ @Fabs 15 Jul
Ah, you essentially only have to use a wallet that also supports the same derivation path, other then that, it's simply words + passphrase, correct?
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Yes.
The simplest thing is to remember what wallet and version you generated your seed phrase with. The next simplest thing is to write down the derivation path. It's not even that long, only as long as a calendar date really.
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13 sats \ 0 replies \ @Fabs 15 Jul
Clear! Thanks, nerd!
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For a multi-sig, you also have to have ALL xpubs for ALL seeds in the multi-sig.
Are just the xpubs enough?
Say I have a 2 of 3 multi-sig using 3 ColdCards with each seed word stored on a separate Seedplate (from CoinKite).
Then, I store the xpub from each ColdCard on a single USB thumb drive. So there are 3 xpubs on one thumb drive.
With only the 3 SeedPlates and the 3 XPUBS, do I have everything required to restore the multi-sig?
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I have to comment on the seemingly strange company shilling in your question, but to answer:
If you have ALL seed phrases, you don't need all xpubs. You can generate the xpubs from the seed phrase and derivation path. However, if you have only 2 of the 3 in a 2 of 3 (say the third one was lost or stolen aka an availability issue) then you need all three xpubs.
xpubs and derivation paths are all about helping you find which utxos belong to you that you can sign. There are other ways you could accomplish that end, but they are more complicated (like storing every Bitcoin address you have ever sent coins to, or storing PSBTs) than just backing up derivation path, script type and xpubs.
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I guess I could have worded my question better. I should have just asked:
"Do the xpubs contain the derivation paths and script types?"
When I open the xpubs in a text editor, the derivation path appears to be there.
So, if I store the xpub from each hardware wallet on an external HD, and then store seed phrase for each on steel, am I good?
BTW, thanks for this post. I'm planning to get a SeedHammer soon because it seems to be the best option. Will it play well with a fully ColdCard multi-sig setup?
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Thanks for the information, @nerd2ninja
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318 sats \ 2 replies \ @sime 14 Jul
I met the guy behind this, personally I think it's overkill, but the lad is a gentleman.
I'll summon him on whatever Twitter is called these days to chime in.
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Just always remember, overkill for you may not be overkill for others. I mean multi-sig is overkill for a lot of people, and a must for others (even with low amounts, just depends on your situation)
If you're a revault user for example, this thing is basically a must.
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I recommend this device (easy to use) 👍
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I've used this, it is a great product...
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As someone who's used it, can you talk more about it? Like did you find it user friendly, do you let your family borrow it lol.
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The software and experience is quite user friendly but you'll need to make sure you understand what you're doing lest you make a mistake.
First, you'll need to generate a few private keys offline. You can use the SeedSigner (same hardware) to do this if you want or hardware wallets. Then you must create a wallet descriptor using these private keys. It is imperative that while doing this you don't expose your private keys on an internet connected computer.
Then, on the SeedHammer controller, you need to enter each private key and scan the wallet descriptor. Be sure to check that the descriptor contains the same private keys you generated in case the computer you used to generate the descriptor is compromised. Then all you need to do is follow the instructions on the screen of the controller which is periodically changing plates. Each plate engraving takes a maximum of 20 minutes. The engraving is very loud though so you should do this in a place where you won't disturb people. I had to stop because my apartment neighbors complained.
The device itself has no memory or storage (it's intentionally chosen because it's dumb) so you can loan it to whomever you want. If you're more paranoid you can use a new controller (Raspberry Pi) if you're borrowing someone's but as long as you personally prepare the SD card (and verify the software) then you'll be fine.
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I see. Sounds like the process could be a little smoother.
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Thanks for sharing your experience
Your neighbors complained about noise, damn
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This company or a similar competitor had a booth at Pacific conference last year
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Excellent! From the first look, it seems a very good tool!
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