My printer has developed an issue where the Y-axis keeps missing steps at random, but ALWAYS in the same direction. Here are some facts about my situation:
-I've got an i3 inspired build, running a standard RAMPS1.4 setup, with nema-17's.
-It ran for weeks withough problems, until this issue popped up.
-The bearings (LM10UU's) are not binding, rods are aligned, and the bed scoots freely when I pop the belt off.
-After a great deal of fiddling with the A4988's, I put in DRV8825's. They seems well adjusted and happy (with the exception of these uni-directional jumps).
-I've lowered my exceleration to 800 on X and Y (though, speed doesn't seem to make much of a difference).
-Belts are tight enough that I can't force them to skip teeth on the motor pully, but still have enough slack to be pinched together and touch each other.
-The motors are not getting hot, but I put heatsinks on them anyways, just in case.
-I have checked, and changed out my wiring for that axis (thought it might have been a loose connection, but it didn't help).
-I've even replaced the Y-axis motor with a nema-17 that has a higher torque rating. The problem lessened, but is still there.
-When it skipps, it's always jumps toward the front or the printer, but not by enough to be a skipped tooth on the belt
-I always know when it happens because I can hear the motor make a KLANK sound, like it ran into something and skipped a step, but there is nothing there to stop it.
This is making me crazy, because I feel like I've checked or changed everything that could be causing this, and it won't go away. I have been watching it when it happes, and it seems completely randon, never in the same spot, or at the same time in a print, and I can't find anything that is binding. Do you guys have any ideas?
Thanks in advance.