Modified the stand to hold a smaller (16mm outer diameter) bearing. Reason being this was the bearing I pulled out of a giveaway fidget spinner I found lying around. This does have a smaller hole so the tip will be in the bearing instead of the shaft, causing more heat transfer, but we will find out if this matters. I think not with the automatic cooldown based on the movement sensor.
EDIT: Maybe if you are using the very thin tip this is good, but it turned out to become too hot (also because it's smaller so less thermal mass). I've adjusted it for a 699ZZ bearing I found.(20mm)
The author remixed this model.