I have an issue with the Y axis which is drifting Here is the result of the print of the result of the Extrusion_Clip_3.gcode file provided on the SD card Do you see on the bottom right the Y drift of about 1mm at each loop.
Here is an other result of a cube print: ( I put the G code of the print as well ) testcube_20mm.gcode.zip (71.92 KB)
What could cause the problem?
The belt tension seems ok to me. I try with many different tensions from loose to very tight, but the result is the same. I've checked as well if there was no hard point on the bed movement, but there are none.
I don't know what could cause this kind on behavior.
It might be hidden by the heatsinks however, and you might need a glass magnifier to see the value.
I tell you this because i happen to have received another shipment of A4988 and the RS value is different. From what i remember yours should be R050 => 0.05 Ohm => 0.3V => 0.75A The one i received are now R100 => 0.10 Ohm => 0.6V => 0.75A
The motors are able to withstand 1.2A and from what we can see 0.75A is enough for this kind of application/motor in order to have a good torque and low heat.
The one we had on our prototypes were R100. From memory you should have the ones with R050 but you post makes me wonder if maybe you have a mix of both :/
Do you remember this axis being hot previously to your voltage calibration?
Also you can try to change this stepper driver with the spare one you should have included in your kit. In rare occasions it happens that some get damaged. Did you use the Ceramic screw driver when adjusting the voltage?