MK3 - Failed print created blob on thermistor cable, cables exposed. Help removing blob?
Good morning, everyone. (ORIGINAL PRUSA i3 MK3 - 3rd Party nozzle, some parts are printed, shouldnt affect print quality)
A week ago, I woke up to a very failed print. I started the print and didn't bother to check the first layer quality, and when I woke up the nozzle had a huge blob around it. I had to go to school, and when I was at school, my dad tried to take off the blob. He succeeded, but there is a problem. A blob of filament is stuck between two (presumably thermistor) cables, which are exposed, and create a loud beeping sound until the printer is turned off. At this point I'm not sure what to do because the printer now fails on the first layer every time, with the plastic on the same height as the nozzle. I don't have a heat gun and I can't melt it without triggering the sensor. What should i do?
Pictures attached.
If you don't have a heatgun there are two other options:
A soldering iron can be used to carve off chunks and may be enough to free your wiring.
Some cheaper hairdryers get hot enough to soften PLA and even PETG in some cases - decent hairdriers have overheat protection to avoid roasting your scalp.
Cheerio,
RE: MK3 - Failed print created blob on thermistor cable, cables exposed. Help removing blob?
Looking at the images, (and I hope I see it well) I would do this:
1. Study this: https://help.prusa3d.com/guide/how-to-replace-a-hotend-thermistor-mk3s-mk3s_131675
- And I have a slightly different approach (because the thermistor will probably be stuck in the hotend)
1a - Heat the hotend up to (200 +) depending on what it is PLA ? PETG? ??
1b When the nozzle is hot, shut the machine off, pull the plug, so yo will not have electrical issues.
1c Remove the thermistor from the hotend (do not burn your fingers!!), but take it out while it is hot (when cold the allen key will not fit, etcetera etc. ) This should be rather easy and can be done in about 10 minutes
2. Is there a connector in the thermistor cables?
If yes, disconnect it, and now lay the thermistor in cooking water. Give it time. PLA and PETG will melt at 100degreesC. And clean it.
If not, make the cables a bit free so you can place a cooker with hot water next to the printer (or on the heatbed whith protection: CARDBOARD/WOOD)
2a. Clean the thermistor as good as possible this way. Dry it and check for disconnections, short cuts, etcetetera.
3. Mount it again. No need to heat it up first. There does not come tension on the thermistor, so do fasten lightly. It only needs good contact to pick up the temp.
And tell us about your results. If might be the thermistor is broken. A new one is not expensive and can be placed in short time
We will do what we have always done. We will find hope in the impossible.
RE: MK3 - Failed print created blob on thermistor cable, cables exposed. Help removing blob?
Thanks for all the help! So far it appears the printer can actually print if the chunk is lifted up slightly, and it won't catch on the first layer. I use PLA Filament, by the way.
I will try with the hotend, and my dad is considering bringing a heat gun back from work, so I will try that too. Does anyone know if the heat gun will damage the printer in any way? Thanks for all the help
Does anyone know if the heat gun will damage the printer in any way?
Yes: remember that the plastic parts of the printer are mostly printed PETG.
Cheerio,