Show HN: Printercow – Turn any thermal printer into an API endpoint • Hacker News Board

Show HN: Printercow – Turn any thermal printer into an API endpoint

#1

Post by lionpixel » Tue, Jan 21, 2025, 11:06 AM UTC

I've always been fascinated by thermal printers – there's something magical about seeing text and images materialize on paper in seconds. But I found that working with them programmatically was always a pain. You either had to deal with ancient printer protocols or use clunky vendor-specific SDKs. So I built Printercow (https://printercow.com) – it turns any thermal printer into an HTTP endpoint with just one command.

Technical details: - Supports any ESC/POS compatible printer (Epson, Star Micronics, etc.) - Handles paper widths from 58mm to 120mm - Automatic image dithering and scaling - Built-in failover protection for high-volume scenarios

Don't have a printer yet but want to try it out? I've got you covered! When you sign-up you get 300 free prints and you can watch your creations come to life on my printer via Twitch live stream (https://twitch.tv/printercow). Perfect for testing your integration before committing to hardware.

I'm particularly excited about the AI integration possibilities. Instead of yet another chat interface, you can have AI generate content that exists in the physical world – artwork, poems, todo lists, custom receipts, etc.

Would love to hear your thoughts, feature requests, or creative use cases you can think of! Also happy to answer any technical questions about the implementation.

Show HN: Printercow – Turn any thermal printer into an API endpoint
printercow.com

Re: Show HN: Printercow – Turn any thermal printer into an API endpoint

#2

Post by lionpixel » Tue, Jan 21, 2025, 2:02 PM UTC

In case you don't want to create an account, you can just comment with your prompts and I will enter them myself. You can watch let it print on https://twitch.tv/printercow then. :)

Re: Show HN: Printercow – Turn any thermal printer into an API endpoint

#3

Post by ksdme9 » Tue, Jan 21, 2025, 2:07 PM UTC

The whole twitch demo thing is genius and fun. Do printer companies usually not provide a first party apps or integrations?

Re: Show HN: Printercow – Turn any thermal printer into an API endpoint

#4

Post by lionpixel » Tue, Jan 21, 2025, 2:14 PM UTC

ksdme9 wrote: post #3

The whole twitch demo thing is genius and fun. Do printer companies usually not provide a first party apps or integrations?

When it comes to regular ink/laser printers: yes. When it comes to thermal printers, you are normally left alone with just the ESC/P protocol, plus most printers handle the commands in a different way. The way I solved this issue is to write an image buffer directly to the printer, circumventing the protocol and always ensuring that prints look the same regardless of the printer.

Re: Show HN: Printercow – Turn any thermal printer into an API endpoint

#5

Post by sometinsome » Tue, Jan 21, 2025, 2:16 PM UTC

Nice! you've built a whole product around and the Twitch demo is great.

In case you need a very basic version of this, I've created a project some time ago, where you can print text over a template, also trough an API and using ESC/POS compatible printers:

https://github.com/emi420/esc-pos-server-print

Re: Show HN: Printercow – Turn any thermal printer into an API endpoint

#6

Post by smokeydoe » Tue, Jan 21, 2025, 2:17 PM UTC

This is really cool. I used to enjoy toying with thermal printers until I found out the paper is coated with a very fine dust of BPA. Still they sell thermal printer cameras on Amazon marketed for children

Re: Show HN: Printercow – Turn any thermal printer into an API endpoint

#7

Post by nolroz » Tue, Jan 21, 2025, 2:17 PM UTC

lionpixel wrote: post #2

In case you don't want to create an account, you can just comment with your prompts and I will enter them myself. You can watch let it print on https://twitch.tv/printercow then. :)

Ok how about a D&D style character sheet for a Lvl 2. Aarakocra barbarian. Lets make it brief and fun with emojis and include prompts for basic rolls and a way to keep track of health points by filling in bubbles or boxes.

Re: Show HN: Printercow – Turn any thermal printer into an API endpoint

#8

Post by heeton » Tue, Jan 21, 2025, 2:21 PM UTC

This is awesome! I have a very hacky prototype doing something similar, you've put way more effort into PrinterCow and it looks great.

What's the tech? (I'm crossing my fingers for Elixir/Nerves but I suspect that's still a bit niche)

Edit, I'm now signed up - though I'm struggling to find the install instructions for the RPi.

Re: Show HN: Printercow – Turn any thermal printer into an API endpoint

#9

Post by lionpixel » Tue, Jan 21, 2025, 2:22 PM UTC

smokeydoe wrote: post #6

This is really cool. I used to enjoy toying with thermal printers until I found out the paper is coated with a very fine dust of BPA. Still they sell thermal printer cameras on Amazon marketed for children

Indeed. But there are some good BPA-free alternatives on the market

Re: Show HN: Printercow – Turn any thermal printer into an API endpoint

#10

Post by echoangle » Tue, Jan 21, 2025, 2:24 PM UTC

lionpixel wrote: post #9

smokeydoe wrote: post #6

This is really cool. I used to enjoy toying with thermal printers until I found out the paper is coated with a very fine dust of BPA. Still they sell thermal printer cameras on Amazon marketed for children

Indeed. But there are some good BPA-free alternatives on the market

Is there any way to verify that without getting a Lab to do an analysis? I'm not sure if I can trust stuff labelled BPA-Free from Amazon for example.