Upgraded Mk2.5S Thermal failures
I upgraded my Mk2S to a 2.5S recently and I've noticed a lot of thermal failures, mostly on PETG I think. Pretty sure, but not positive the print dies when the fan kicks up to 50 (PETG stock settings for cooling are 30 to 50).
After some googling it seems the cause could be the fan speed or to add a silicone sock, which I guess keeps the air off of the heat block and keeps it from overcooling.
As luck would have it I bought E3D socks years ago for another printer and just cleaned the block and installed it. Going to try my print again with no change in fan settings to see if it completes this time.
I am on the right track here or is something else going on. Everything on the block looks good, thermistor, etc. and the temp doesn't dance around at all. It stays very constant.
RE: Upgraded Mk2.5S Thermal failures
I think I was chasing my tail. I've seen this happen once before. I'm printing two large items and it stops in the EXACT same place now on 3 different prints. The screen says "Thermal Runaway".
I put the sock on and it keeps filling up and falling off. My conclusion is that the nozzle might be a little high. So I pull the sock off and print the pieces one at a time. Watching them the whole time in boring misery so as to catch a thermal runaway start to happen.
Printing the pieces individually indicates no problem whatsoever. No fluctuation in fan speed. Fan stays at 76 the whole time on both prints. Netting me two perfect prints.
Somehow or another the slice of both parts together is problematic.
Seems I was chasing a hardware problem that I don't have.
RE: Upgraded Mk2.5S Thermal failures
@hagensieker
Thermal runaway can also be caused by poor connection of the heater either at the MiniRAMBO connector or at the wire crimps very near the heater element. Sometimes it takes awhile for the poor connection to affect heater operation, so you might get a shorter print completed. Also, just working in the vicinity of the fault can temporarily correct it. Like installing a sock on the hotend can jostle a loose heater element crimp connection.... (don't ask me how I know 😉 )
¡no entiendo Español!
Nein! Nicht Versteh!
Я немного говорю по-руÑÑки но не очень хорошо, и...
I'm not very good at English either! Maybe someday I'll find a language I'm good at?
RE: Upgraded Mk2.5S Thermal failures
@hagensieker
Thermal runaway can also be caused by poor connection of the heater either at the MiniRAMBO connector or at the wire crimps very near the heater element. Sometimes it takes awhile for the poor connection to affect heater operation, so you might get a shorter print completed. Also, just working in the vicinity of the fault can temporarily correct it. Like installing a sock on the hotend can jostle a loose heater element crimp connection.... (don't ask me how I know 😉 )
I gave it a real good shakedown yesterday. The one thing that I did do was a 285 degree nozzle tighten down. Printed maybe 8 things after that with no sock and no thermal runaways. Pretty sure it was that slice with maybe some nozzle touching heat brake looseness. It wasn't what I'd call loose but it did turn a little.