"Skipped???" steps

Ive been fine tuning my printer and its been a nightmare with my steppers and their drivers. I have adjusted all reference voltages to .4 as ive heard.
It keeps missing steps, but consistently... in the same spot somewhat repeatably.

This is so frustrating.

Whats wrong... bad driver? Bad motors? Bad controller? Bad me?
Has anyone seen this before?

-Nick

Can you upload a video; here is what it could be

Non straight rods or rods not aligned, and non greased bearings.

loose belt, loose gear, power level set too low, acceleration speed set too high, homing rates and feedrates in general set too high,

Also stepping mode not set correctly. Most firmware currently defaults to 1/16 micro stepping. Are you sure the steppers drivers are set correctly for the micro steps?

If it's always in the same spot, I'd bet for mechanical friction. And having sufficient juice to the motors is more important than sticking to myths.

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Generation 7 Electronics	Teacup Firmware	RepRap DIY

Check the motor while running for temp. in the direction that skipped, if there is no fan on the motor they can get very hot and skip. I had the same problem and put a fan on the offender and it stopped skipping. My $.02

Well ive found it was my GT2 pulleys slipping... they keep coming loose no matter how hard i tighten them. How can I keep them from loosening up?


-Nick

I put a drop of superglue between the end of the shaft and pulley after mounting the pulley, and a little on the set screw.

From the end of the shaft, the glue will capillary inbetween the shaft and pulley.

This has kept my pulleys tight, and isn't too glued to take the pulley off if necessary. Superglue doesn't overly adhere to the smooth metal of the motor shaft, but is enough to lock down the pulley from coming loose.

Do your motor shafts have a flat spot for the set screw to tighten against?

Edited 4 time(s). Last edit at 01/23/2013 06:52PM by Dirty Steve.

Yes

-Nick