Thermal Error with small prints

Just an FYI. I have a couple of Taz units. Been using them for many years. The shop has piles of prototype parts that have been printed with them. The issue is that every once in a while I do some really small prints - a first layer that is less than about 1 square inch in size - and I almost always get a thermal error after a few minutes. I am printing PC at 260 with the bed at 100. This error doesn’t happen when I print the smaller parts with some bigger parts. My theory is that the error occurs because the print head is laying 260 degree filament on top of 260 degree filament on top of 260 degree filament, etc. until the thermostat in the bed decides there is a problem. I assume this doesn’t happen with larger prints since then the filament cools down before a new layer is added. Just thought I would post this in case someone else runs into this issue some day… If you have another explanation, please let me know. Thanks.

Are you watching the temps when this happens? Thermal errors also occur when the nozzle gets too cold from part cooling fans hitting it.

I’ve done a few small gears (about 20mm radius) in PC and had no issues with heat on a Mini 2 without an enclosure.

I am not watching the temps. Is there a log? It turns out it is not related to the bed, but happens at any point where the print layer is about a square inch or smaller. Are you saying that if I turn off the fans, the error might not occur? That could be the problem. Cura’s settings for Polymaker PC-Max leave the fans on, but Polymaker’s specs for PC-Max say turn the fans off. I will try that. Thanks.

Watch the temps on the taz’s screen, since you say it’s happening pretty consistently you should be able to see if it’s too high or low. If you’re using Cura LE to send it, you can see a graph, but it doesn’t log as far as I know.