[BOUNTY CLOSED] Open Source (CC) Paper Wallet Kit for safe offline coin storage

[aantonop]

I assume your kit is meant for "average" users? If so, isn't the software arguably the most delicate component of this? Since I do not see that it has been explicitly mentioned here, your kit should include something like a bootable DVD or USB stick with secure software pre-installed on it, together with easy-to-follow instructions on how to verify the checksum. Also do not forget that since you are booting into a more-or-less known state it is absolutely essential to introduce enough entropy before generating any random numbers, etc.

Very good suggestions proff!

Indeed, it is meant for the newbie, not even the average user. Once you have more than say $500 you want to keep it offline, so that's the target customer/user.

My initial thought was to have the user download the software from openpaperwallet.com, go offline, run it and print. A key part of this project will be the user instructions, which I am writing now and will hope to get help illustrating.

Now, if people think that download-offline-print is too insecure or prone to hijacking, we could add USB keys into the retail product, but that would be up to individual resellers.

Since I hope to be the first reseller of these as kits, let me ask the community here: USB stick or download?

[1713892039]

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[1713892039]

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[aantonop]

Must have missed the part about the use of diecut perfs. In that case it might be a good idea to only use horizontal gradients to fix most of the problems.

I am meeting with printing companies today to start conversations. I'll ask about perforation, but here's what I know already:

- These services are called "bindery", which includes cutting, folding, stitching, foil, numbering or other post-print features.

- It costs about $10-$15 per CUT LINE. So if instead of 5, we want 10 lines, it means an extra $50. Not a huge deal, on a $500-$2000 print run.

- There are different types of perforations, depending on the shape and size of the cut. Shapes like "[", "|","L" repeated.

- Micro-perforation is a marketing term for finer cuts.


The biggest thing to find out is the accuracy they can deliver.

The other thing to keep in mind is that a perforation has width. Not much, but some. So the edge will be frayed after tearing even with a micro-perforation die. If you've received a payment cheque in the mail, the type that have a printed statement stub on half the page and a cheque on the other half, you have seen what the industry calls "micro-perforation". It's not as good as an exacto knife.

[aantonop]

LOVE the new ones, especially the red and purple. Not colors you see on banknotes often, which makes them even better. Great job Timbo.

[batcoin]

I still haven't had any time to play around here. Plus all the designs here look so much better than what I could come up with. I had an idea to add though... What about somehow including a watermark or some way for the end user to also print the initial amount loaded on to the paper wallet? Of course people could add more later if they wanted, but at least they would know the minimum amount that should be held in the wallet.

Perhaps something similar to this design?

I was also thinking of something with kind of a trailing full amount like this:

10.12345678

Or doing the ¢BTC, mBTC, µBTC like this:

10.12345678

Maybe with the denomination just above the corresponding numbers?

I imagine most will want to just put a round number on their notes, but who knows? It might be nice to have something like this and I think it helps with readability.

[acorn]

I have updated my previous design to comply with the new layout template.

Licensed CC-BY-SA

[TheMildChaos]

My initial thought was to have the user download the software from openpaperwallet.com, go offline, run it and print. A key part of this project will be the user instructions, which I am writing now and will hope to get help illustrating.

Now, if people think that download-offline-print is too insecure or prone to hijacking, we could add USB keys into the retail product, but that would be up to individual resellers.

Since I hope to be the first reseller of these as kits, let me ask the community here: USB stick or download?

I think what should be done would be to include checksums or something of the like of which they can verify for themselves that any tampering hasn't been done to the software, regardless of how its delivered. That being said, it's probably cheaper to offer the software as a download.

https://i.imgur.com/vIKaY2l.png

I never did figure out how to do those curves in Inkscape... Is there any particular guide to drawing those, or is it just experimentation by hand?

[Timbo925]

@TheMildChaos

You can do this in illustrator by just drawing one line. Then use the option Effect > Transform > Transform
This lets you just duplicate the line and move/scale/rotate it with every copy. With some tweaking you can get some nice shapes.
Over the years I also found some of these shapes only so that also helps

-----
Some new designs added to while I'm messing around in illustrator watching the charts 
https://drive.google.com/folderview?id=0B1-OuUkg4oEBRC0tVTFIM0ZuSUU&usp=sharing

[canton]

One last point: I personally believe there is no need or purpose for the PUBLIC key on the stub, for two reasons. Firstly, you don't need to load a wallet often, It's better to make a new one for security. Secondly, you can recreate the public key from the private key import. So having the private WIF is enough to get the receiving address back. I'd rather have two copies of the private WIF on the stub to double my chances of recovery, than waste one space for a public key I won't use.

Does anyone else want to weigh in on this before I adjust my own design accordingly?

In my current design, the tear-off stub shows the private key twice (once as QR, once as alphanumeric) and the public key twice (once as QR, once as alphanumeric.) To me this seems like the right balance of redundancy and usability. I'm reluctant to redesign the stub in such a way that it's more difficult to quickly check the public balance.

I understand that not everyone will make use of a public QR code on the stub, but since some people will want to be able to quickly verify their balances by using stubs from time to time, and since the private code is already printed twice for redundancy, why not include a public QR code?

Here's my current stub design for reference.

[canton]

Aantonop,

Is it possible to leave an impression on your scratch-off stickers by pressing a hard plastic shape onto them? I'd test with a LEGO since that's similar to the plastic used in 3D printing.

If so my idea is that in your high-end "pro" kit you could also include a little plastic stamper (shortrun 3D printing) that would let you press a subtle bitcoin symbol onto the scratcher. I'm guessing there's no point in trying with ink since the scratcher material is probably some kind of wax/non-inkable surface.



If this ins't at all possible maybe there's some way you can prepare the scratchers before shipping them so they have a bitcoin symbol on them. Maybe there's *something* that will stick to that surface... Maybe if you make a metal stamp and then heat it up?

It's not my intention to make this any more complicated/expensive than necessary. However I think there's a marketing benefit to making something in your kit fairly unique, something that can't be purchased off-the-shelf, something that would be the purchase tipping point for someone who would otherwise just print their own and buy their own scratch off stickers.

[canton]

Some new designs added to while I'm messing around in illustrator

I love the dark colors! However I think you'll want to be *much* more generous with the whitespace around printable areas, since if the ink misses the mark by just a bit, the ink won't be readable against the background.



Additionally important for QR codes which require a fairly generous whitespace around them to work on many devices.

This week I've been testing high-resolution printing from web browsers, and the variance (even from browser to browser, much less printer-to-printer) is shocking. I'll get printing to work perfect with Safari, and then I switch to Firefox and my prints are 20% bigger and shifted to the left. Oi! Getting an accurate print out of a webpage is going to be a tricky, even with giving folks good calibration tools. Unless someone can get the CSS working a lot better than I have, what I think we should aim for is a design that succeeds to be readable (even if a little offcenter) when the user's prints are:

* up to 1/8" offset vertical and/or horizontal
* and also +/- 10 percent zoom offset

I am actively working on some javascript that will hopefully guide users to calibrate their output for zoom/offset, but in my opinion our final design should anticipate and still succeed when there's significant variance.

[Timbo925]

Glad you like it. I used the white space included for in the template so will keep it this way for now. But shouldn't be a problem to do these little edit if requested.

To fix the printer problems wouldn't it be a great idea to generate pdf files. The only thing the user needs to do is to generate the page and print it at 100% and centered.
You could supply bills like this.


With these you can then print a test bills, to see what offset you need to put into the software. Add your offset into the pdf generator and it would supply the correct pdf to be printed with your own printer.

[aantonop]

If so my idea is that in your high-end "pro" kit you could also include a little plastic stamper (shortrun 3D printing) that would let you press a subtle bitcoin symbol onto the scratcher. I'm guessing there's no point in trying with ink since the scratcher material is probably some kind of wax/non-inkable surface.

It will be a lot easier to simply order custom scratch-offs, pre-printed at the factory.

They come in a roll, like a tape dispenser or a roll of stamps. I will cut strips of 10 stickers and pack 5 of the strips in each kit.

Love the idea of custom stickers for the pro kit. It will be a lot easier to do as a pre-printed order, I will share my supplier info.

Finally, we can also add a custom emboss, foil, raised ink or watermark to the paper (for added cost) at the printing shop.

I will be getting the first printing quotes early next week, I've already sent the specs to three printers. I'll let you know as soon as I have a better idea of the possibilities and costs.

[canton]

To fix the printer problems wouldn't it be a great idea to generate pdf files.

That would be *awesome*. I've had the same wish. I wonder if something like this would work. http://jspdf.com

[acorn]

That would be *awesome*. I've had the same wish. I wonder if something like this would work. http://jspdf.com

I'm a little concerned about using js in a tool because if the js is used locally, some browsers require you to go into settings to allow local access (we could make a note about this in the instructions though), and hosting the PDF generator online is also a bad idea because then the QR codes etc are being transmitted which is something we wanted to avoid.

[acorn]

To fix the printer problems wouldn't it be a great idea to generate pdf files. The only thing the user needs to do is to generate the page and print it at 100% and centered.
You could supply bills like this.


With these you can then print a test bills, to see what offset you need to put into the software. Add your offset into the pdf generator and it would supply the correct pdf to be printed with your own printer.

Agreed, if we can build a tool that forces the printer to disable scaling to fit paper size, it should be manageable once the user has tested a few of the calibration sheets out. If for whatever reason the printer creates an offset, the tool should allow the user to adjust the x and y position and try again.

[aantonop]

I just received the first set of quotes from the printers:

Multi-Part
1,000 Digital Color, 8.5 x 11 Bright White 80# Mohawk Color Copy 98 Cover
28.76, digitally printed on 2 sides
Perforation 3 horizontal by 1 vertical

$1,182.75 + Tax

5,000 Digital Color, 8.5 x 11 Bright White 80# Mohawk Color Copy 98 Cover
28.76, digitally printed on 2 sides
Perforation 3 horizontal by 1 vertical

$4,767.00 + Tax


Cost basis:

1 sheet (4 notes) = ~ $0.95 - $1.18

A paper wallet kit (10 sheets, 40 notes) = ~ $9.50 - $11.8 (wholesale)
120 stickers = ~ $4.8
Misc sheets, envelope = ~ $2

Total = ~ $17 wholesale for 40 paper wallet kit, at first production run.

I think I can get it down to about $13 with a bit of haggling and a larger order of each component. That would allow a retail of $18-$25 per kit, with a reasonable profit.

Comments? Thoughts?

[aantonop]

https://github.com/openpaperwallet/openpaperwallet

OpenPaperWallet repo has been moved to its own organization.

Please follow/star/fork as you need. Pull requests for designs/code are now welcome!

Anyone interested in co-admin of the repo, let me know to add you.




Let's start filling it up!

[canton]

Hey everyone, I did something REALLLLLY foolish:

You know those mockups I posted of my design in this thread? The QR codes contained a live public address AND private key with a small balance (.026 BTC) -- part of an unrelated competition I was running. Dumb dumb dumb...

On April 11 the wallet was swiped before the competition even began:
https://blockchain.info/address/1LMKzdqhQ4LhHy5GGhT8BcG3HHpBTqAqbt

If you're reading this thread and you swiped the wallet by cleverly reading the QR code off of the mockups I posted to this thread, would you please please let me know? You can ping me at canton@gmail.com. This would be much more reassuring than the alternative explanation I have which is that my computer or internet connection was hacked.

In fact, if you can prove you were the person who emptied the wallet, I'll gladly send you *another* .026 BTC for your trouble.

Thanks,
- Your friendly village idiot

[aantonop]

Don't beat yourself up. Key management is hard.

I've seen it happen on reddit three times. I scanned QR codes of one of the notes on another post on reddit, just to see if it  was possible but I didn't take the balance, I warned the OP.

Good luck!

[zakoliverz]

good idea !
I love the design layout.