Idler Arm Finally Cracked on TAZ5

Printed up a replacement, around 3 months of use, just thought I’d use this thread to remind users to check if the idler arm is still intact as it can cause filament to stop feeding and grinding.

Good point brendan! There is a heavy duty one on the Lulzbot site. There is also a heavy duty direct replacement for Taz 5 and Mini to download & print here:

Hello Brendan,

Here is a link to the modified idler:

The original had a smaller diameter for the bearing to fit in to and ultimately caused the splitting due to the pressure from the bearing. This one should take care of that issue for you.
If you can, print it out of ABS or something durable, for longevity!
Hope this helps.

Hey David,

That’s the one I printed out, what’s interesting is that it cracked perpendicular to the bearing’s shaft, as if the shaft was too long for the slot and wedged the halves apart. Regardless, I had it printed at 75% infill in ABS as recommended.

Hello Brendan,
That is strange! I wonder if it was due to the thermal swell of the filament. Perhaps it caused the location for the shaft, to be just a bit too small. It would be hard to say! When you print this one, maybe turning the part cooling fan off for the print will allow it to set up with just a slightly larger slot for the shaft.
Good luck on this one!

I had to replace the idler on my Mini last night as well. I had already printed an ABS replacement using the new design from Lulzbot, and swapping it out was pretty easy. I think I’ll print another one, and maybe the one CoParaTech designed as well while I have the ABS loaded. Might as well have spares.

Another spare that would have been handy was a fan shroud for the heat-break. I replaced the blower with a 25mm fan and it had a connection issue in the middle of a print and stopped. That in turn caused the shroud to melt a bit on the heater block. I cleaned it up, but the shroud was damaged and air leaked out onto the heater, it was only able to maintain about 215C. Thankfully, that was enough to print a replacement. Now I have a spare one printed as well. :slight_smile:

Here’s a pic of where it fractured: