Just want to say that I still have an almost full tank of CO2 lasing gas mixture and a regulator and other misc stuff if anyone is interested. I hear helium is very scarce these days so this gas will be hard to source (it has some helium in the mixture).
So far just manual control. I was thinking of using Arduino. I'm still trying to think of some clever and cheap DIY scanner, using speaker drivers. I have them laying all over the place at work.
No, no sarcasm. Here is mine:
https://www.banggood.com/RGB-300mW-White-Laser-Dot-Module-Red-Green-Blue-638nm-520nm-450nm-TTL-Driver-Modulation-p-1252293.html?rmmds=search&cur_warehouse=CN
Yes, I have seen that done on YouTube, using a balloon and calipers or something to measure diameter and calculate volume. I probably will try that but just thought this would be simpler to start. Does the pressure in the resonator change as the balloon deflates?
You didn't mention N2? Is...
SOLVED
I found a supplier. SCI Analytical (http://scicalgas.com/). They will mix whatever you need and ship it. Prices seem reasonable, and they are very hobbiest-friendly.
I'm going to start with a known good mixture and get everything else working, then maybe experiment with my own mixes.