Sort:  

Yeah PCB and stuff but because it’s built out of extrusion I’m thinking it would scale up nicely

Cool.
For the extrusion you are using 2020, 3030 or the biffy 4545 ?
I am thinking about putting external TB6600 stepper drivers to put reliably 2A in my stepper motors, do you have any experience with those ? I found a set of 5 for less than 30 $.

I have a bunch of 2020 here so likely use that. Not tried those stepper drivers :)