That card looks awesome!
If you’re having any issues with inaccuracy at all…. From my very limited experience, a very worthwhile tuning step that requires no special tools except a free iPhone app, is tensioning the belts.
Shapeoko will work just fine without this step, but I felt like it gave me a big jump in accuracy early on. By doing this, I found that what I thought was good tension was way too loose.
Quick overview: you measure out a 50cm length of belt, peg some 1/4” bit shanks under each end of the 50cm, pluck the elevated section like a bass string, and read the hertz on a free iPhone app (Gates Carbon Drive). Then, adjust the tightness of each belt until they’re all equally tensioned. I think I did mine to about 80hz, and I’m very happy with how it cuts now.
There’s a link below with a lot more info on this. .
Tramming is the one step that is a bit involved - a tramming gauge makes it easy but lots of folks have made their own homemade gauges. Having tried both, I definitely prefer to use a dedicated gauge, but they can also be pricey. Only worth it IMO if you’re noticing angled cuts along the x-axis. Probably won’t matter much at all for etching.
Looking forward to seeing your projects come to life, Smokey!