MakerBot Industries

Just a thought, is the thermocouple close to the cartridge heater? It could be that when the extruder heats up it expands just enough to touch the cartridge, which I think does have the ability to get up to 380C (or more, rated for 500), which should flip the safety cutoff and shut off the extruder. Does the light on the cutoff go from green to red? Have you tested the cutoff to make sure the led is working?

BTW, I know this is possible because on my ToM the little bolt holding down the thermocouple got loose enough after a while to let the wire move and suddenly it was reading way too high and I couldn't print, the cutoff was triggering. Carefully bending the thermocouple so it completely fit under the washer solved that problem for me.

Also, I understand your frustration, but these things do work, I've got two of them, and once that the bugs were worked out both have printed reliably for many, many hours. So hang in there. Also, I have found the MBI support staff to be very helpful, if you haven't already I would suggest opening a ticket.

Hi Steve,
Did you ever work this out?

I have exactly the same issue - with the ambient temp toolhead readings being at 50 and the ABP (rather than the HBP) being at 20.

I also noticed the extruder being turned off when I am trying to heat the ABP and he extruder at the same time. The ABP works when I heat it by itself, as does the extruder - but I can't get the extruder to get above 210C.

I'm working with one of the guys at Makerbot so if I manage to work out the issue I will post here with the fix.