I’ve got everything up and running fine, just have a few questions/problems with skipped steps (primarily in one axis, though it can also happen in both).
- I’m using 4x NEMA17s with A4988 stepper drivers off a 12V ATX power supply, the X and Y driver VREFs need to be at least 800mV before I get smooth movement. Is this VREF normal for steppers running in parallel? I noticed a few other posts that mention 500mV for X-Y VREF, but not sure if this is the same for parallel motors.
- How snug should the conduit pipes be between the bearings? I’ve noticed a few skid mark tracks on the cross pipes from bearings, but they don’t snag or stop when I push them back and forth. I’ve even sanded the pipes down a bit to increase smoothness, do they need to roll freely when the steppers aren’t connected?
- I’ve tuned down my acceleration and xy jerk to nearly half of what’s posted on the Marlin firmware (about 600 for accel and 4.0 for xyjerk), are there any other settings to help reduce resonance-related belt skipping?
This is a great design, hopefully I can fix the layer offset problem and get started on printing the clamps for my DW660. Thanks for the help!