PLA melted all over hotend and thermistor wiring, printer says 700+ degrees
I was printing something and adhesion failed at some point over night, and the hotend filled itself with melted PLA.
Now, when I turn on the printer it thinks it's at 700+ degrees and never stops screaming. I had something similar happen before months ago but the thermistor was fine so I was able to heat the printer for a few hours until the PLA melted/burned off.
Thoughts on what to do?
RE: PLA melted all over hotend and thermistor wiring, printer says 700+ degrees
https://help.prusa3d.com/en/article/extruder-blob_2005#how-to-clear-the-extruder-blob
RE: PLA melted all over hotend and thermistor wiring, printer says 700+ degrees
That looks like an improperly installed nozzle. This allows a leak because when the nozzle is not in contact with the heat break, plastic drips out the heat break threads and builds up over time and eventually causes a crash that knocks the part loose or stalls the printer if crash detect is off.
Net result is a blob.
Or not ... but the nozzle does look too tight against the heater block.
As for 700c: the aluminum heater block would be melting. Probably carbonized plastic acting as a conductor around the thermistor leads.
RE: PLA melted all over hotend and thermistor wiring, printer says 700+ degrees
Thanks folks! I bought a variable temp heat gun on Amazon last night to help loosen the goop.
Can anyone recommend what temperature I should set the heat gun to for loosening/melting off PLA?
RE: PLA melted all over hotend and thermistor wiring, printer says 700+ degrees
Thanks folks! I bought a variable temp heat gun on Amazon last night to help loosen the goop.
Can anyone recommend what temperature I should set the heat gun to for loosening/melting off PLA?
Just remember that the heat gun will melt things like the wire brush handle you're using for cleaning. I had the best luck just bracing the hotend and heating it up, then using strips of corrugated cardboard and toothpicks to clean stuff up.
With any luck, you'll only need to replace a part or two. However, be prepared for the eventuality that the heater block, thermistor, heater cartridge and maybe nozzle are fused. Ordering spares ahead of time is recommended! Get some thermal paste (for top of heatbreak-heat sink) while you're at it. This is a good opportunity to order and install a replacement non-Prusafied E3D heatbreak without the 2.2-2.0mm step.
RE: PLA melted all over hotend and thermistor wiring, printer says 700+ degrees
@bobstro thanks for the advice! The variable heat gun I purchased can do 140F to insanely hot temps. I've never used a heat gun, do you recommend a temp that's low enough to minimize risk to myself or printer parts, but hot enough to loosen the PLA?