Do the timing belts ever wear out?

[helix_3]

I'm starting to notice small amounts of layer slipping on prints. I plan on re-tensioning all the belts, but is it possible this slippage is due to the belts wearing out? Should they ever be replaced?

[willnewton]

Layer slipping, as in the print looks as if it has shifted over?

I have had that happen occasionally on very tall prints for no reason I can understand. I have had it happen on shorter print where there has been an obvious print head collision that has knocked the axis off kilter. I have also had it happen while printing if I try to access the print computer via wireless network, such as sharing the screen to check the print progress via S3D.

Is it in every print? Every file? Do it occur at the same location each time? Does occur every time the axis moves, not just once in the print? It may be mechanical. Check your bolts and pinions and belt clamp. It might not hurt to make sure it is all snug.

Let us know a few more details and we'll try to help you out.

[ednisley]

the belts wearing out?

In this lightly loaded application, those belts should last just slightly short of forever... [grin]

What's more likely is that the little tiny screw that should lock the pulley to the motor shaft has worked ever so slightly loose, allowing backlash that offsets the threads from layer to layer. It's worth checking before you vanish into the rabbit hole of configuration twiddling.

If the screws remain tight, then reduce the X and Y acceleration by a factor of two, in order to expose mechanical problems impeding the platform motion. The motors produce a fixed amount of torque, so when the load increases beyond what they can handle, you'll start to see missed steps. That will be a hint to check for crud in the bearings, lubricate the slides, and so forth & so on.

Catch those problems early and life will be much easier!

[jdacal]

Its happened to be once since I got my printer. It got progressively worse as the print continued. For me it was a cracked X-Axis motor mount. Look for hairline cracks in it, especially around the hole on the right side and on the lower left side.

[helix_3]

Thanks for the advice, everyone! I did a few tests, and have come to the conclusion that the extruder motor is to blame. The pinion gear on the stepper's shaft was slipping, so I added a few drops of superglue to lock it in place.

This helped keep the gear on, but the connection isn't strong enough to support high print speeds. The gear would occasionally slip, leading to underextrusion and what looked like layer slipping.

[Capt. John]

Allen set needs to be tightened in the drive gear if I'm reading this correctly.
Super Glue by itself will not fix this issue.