Printing private keys for cold storage

[W2014]

I've set up an offline wallet (Armory - Ubuntu OS - offline computer) and now want to print the private keys as a backup in case my offline computer (older laptop) crashes/dies.

What type of printer can I use to be sure that the printer does not store the private key data? Which type of printers should be avoided? Any advice/suggestions would be appreciated. 

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[minzie]

Unless you are using a commercial grade printer with hard drive in it, there will not be a record. In a typical home printer, memory is flushed as soon as the power is shut off. Basically, any $30 off-the-shelf printer will suffice. This may be useful to you.

[Bernard Lerring]

I was thinking about this today:

How about using a Dymo for printing out a private key and sticking it to a card inside an envelope?

Not the old punch type ones. The newer thermal ones, like this:

http://www.amazon.co.uk/Dymo-LetraTag-LT-100H-Label-maker/dp/B0030453IM/ref=sr_1_14?s=officeproduct&ie=UTF8&qid=1408988286&sr=1-14&keywords=labelling+machine

Would this be any good?

Does anyone think that the print would fade after, say, 10 years inside a sealed envelope?

[Abdussamad]

I've set up an offline wallet (Armory - Ubuntu OS - offline computer) and now want to print the private keys as a backup in case my offline computer (older laptop) crashes/dies.

What type of printer can I use to be sure that the printer does not store the private key data? Which type of printers should be avoided? Any advice/suggestions would be appreciated. 

If you are using armory you should not print out the private keys. Just the root key will suffice. Armory is a deterministic wallet which means that all address specific private keys are derived from the root key. The root key is all you need to backup. To backup the root key double click on the wallet > select "backup this wallet" and then "printable paper backup"

[ForgottenPassword]

I've set up an offline wallet (Armory - Ubuntu OS - offline computer) and now want to print the private keys as a backup in case my offline computer (older laptop) crashes/dies.

What type of printer can I use to be sure that the printer does not store the private key data? Which type of printers should be avoided? Any advice/suggestions would be appreciated.  

I recommend getting a paper and pen and writing it down manually. Some printers have a cache that will save the backup, also if you are using a networked printer an attacker sniffing your network will be able to get your backup.

Armory paper backups aren't that hard to write out.

EDIT: You need to use the backup feature of Armory to do this. Don't write out the private keys themselves, Armory wallets are deterministic, you only need to make one paper backup and you're good to go forever, no need to make additional backups when you add new addresses.

[Bernard Lerring]

What about a thermal Dymo machine for printing out and sticking private keys inside an envelope?

£20 from Amazon and once the batteries are removed I doubt any memory will remain.

Seems like a good idea to me. I only question how readable the print will be after a few years cold storage.

Any thoughts? I don't want to go through the hassle of punching characters into a sheet of metal, as has been suggested on these forums before.

Not that I think using metal is a bad idea: just too much effort for me.