So I am finally getting back to this adventure and have a few things to share. First, the plate job went great. The only problem I had was caused by the cheap shaft couplings I used. One came loose in the middle of a run. Luckily, I did not have to scrap the part. Here is a picture of the final product:
I have started to chase down the small things now. I calibrated belt tension and steps per mm. With that done, I was able to hit tolerances of +/- 0.0005" in delrin without too much effort other than a finishing and spring pass.
I am pretty happy with that but I do have an issue with keeping the machine square. Even with the machine frame being square to my fixture plate and me pulling the gantry against the stops when I power it up, it doesn’t stay square. I have found that the steppers don’t consistently rotate to the same full step position when I turn the power on. I haven’t tried using shims between the frame and the gantry on power up but since the amount it is off square varies, I doubt it would really help.
I know I said in the beginning that I would not be changing out the controller… I have changed my mind. After a couple weeks of trying to solve my squaring issues I have come to the conclusion that I need the machine to square itself during homing. That means I need to have another sensor on the Y axis. I think there are ways to do this with GRBL but if I am going to replace the controller, I would rather just go with another type. I will be switching to Mach4 and an ESS. I picked this because I am already familiar with both and have experience customizing them. I am also motivated to switch controllers in order to have a machine at home that I can prototype Mach4 customizations without interrupting my work machine.
I plan on keeping all the existing connectors and homing sensors so I can go back to the CM board if I ever want to.
I have the ESS, power supplies, cables, connectors and breakout boards already and have started on wiring everything. I have one more 5v proximity sensor coming for the second Y limit sensor. I will post pictures when I am done wiring the electronics.
Does anyone know off the top of their head what the microstepping is set to in the stepper drivers on the CM board? I’m sure I can figure it out if no one does. EDIT: It looks like the answer is 8x microstepping.