Error 57 - Heater Temperature Sag Triggered

[ESAAA lab - fab manager]

Hi everyone.

We have a Makerbot 5th Gen, and as you all know, the "smart" extruder is pretty temperamental, to say the least.

Recently, we started getting a lot of error 57 during the prints. We figured that the somewhat cryptic "Heater Temperature Sag Triggered" message (at least for us non-native english speakers) actually meant that the hot end was too cold, and that message popped up just when the temp reached 194°C (instead of the 215°C default temp for PLA). So it looks like that <195 triggers the error (which raises the question of printing with lower temp filament : will it still trigger ?).

In the past, we had to take the extruder appart quite a lot of time in order to unclog and clean it thoroughly, so the little insulation that was surrounding the aluminium heat block started peeling away. That missing insulator was the reason for the errors, because heat was escaping too quickly for the head to stay hot enough.

We replaced that little insulator with some kind of fiberglass sheet that we found wrapped around the heating element from an old expresso machine, cut to size and taped to the extruder's heat block.

After that fix, we were able to launch a couple test prints (around 1:30h), a 40h print, and a 12h print job is currently running. The hot end always stays around 210-215°C.

Little tip for you next cleanup : the 3 bottom rows of pogo pins on the back of the smart extruder are directly wired to the heater, so we plugged a lab PSU to the last row's couple of pins, and dialed something like 6V. The heater block got hot enough (around 140°C) for us to wipe it clean from all the accumulation of black burned out PLA residues. We might build a small bed with contacts, clips, etc to be able to make the extruder heat and read the temp while cleaning all the components outside of the machine, but we'll have to take time off printing (and all the other stuff we're doing) and re-trace the PCB to make sure we're not damaging any components inside.

[tramalot]

I have bought a mini onebut  yet but most peole say return it..... I scraped a mini and see no redeeming blocks/ trails... win 8 sklls