The Blob
So the one time that I don't check on my printer every half hour, I come back to find this:
I could go at this mess with my Dremel, but that would probably take a long time and make a huge mess. I have a bench-top power supply, and I am considering hooking the hot end connection up to it and heating the cartridge until i can pull the blob off. what do you think? A terrible idea? What amperage do I need to set the power supply to? The hot end is the 24 volt version.
RE: The Blob
is that PLA?
your heater should be 40 watts.
40 watts at 24 volts is about 1.8 amps.
BUT you don't want to toast the hot end...
so if your power supply is variable voltage and variable current.
I would start off with say 12 volts and limit the current whilst everything warms gently...
the heart of the blob will warm faster than the outside, so be patient and let it warm through.
Can you peel the extruder housing off the hot end assembly?
the extruder housings are PETG, so they should be more robust than the Blob, (Assuming it is PLA)
the thermistor wires are extremely fragile so be careful...
if you can, nibble the bulk of the mess off with cutters(use a cloth or gloves to protect your hands, ) when you get down to the heatblock, and the thermistor is safe, consider heating hotter and using a brass brush to clean the heat block up
Good Luch
Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
RE: The Blob
welcome to the blob club.
the heater heats up well at around 14 volt. so you should be fine.
take it slow, but I do feel turning the heater on is the best thing todo
I have a Prusa,therefore I research.
RE: The Blob
Honestly, from an electronics perspective, I'd not try a direct connect. The 40w heater element is probably nicrhome based and you really have no idea what the power will be unless you review a chart for the specific heater vs voltage point. It's probably safe to say a 24v heater will heat less at 12v, but you really can't be sure. And you also can't see the temperature it is getting to... so you risk burning it up, and the thermistor in the heater block. And inside an insulated mess? It's going to get very hot very quick, and you'll probably end up with a fire.
Connect the hot end to an operable Einsy/controller that has a reasonable thermal control for it. Set the temperature to something nominally below the melt point of the plastic, and start there... increasing a few degrees as needed to warm the blob slowly until you can start picking off pieces.
RE: The Blob
Or just put the whole thing into an oven at 60°C. The PLA will become soft and rubbery, the PETG will survive intact. No issues with potential overheating without a thermistor feedback loop.
RE: The Blob
Do not put the blob in an oven .. exposed radiant elements can easily destroy the parts you are trying to save. If you try something like this, make sure to place the blob inside a metal baking shell of some sort.
RE: The Blob
Do not put the blob in an oven .. exposed radiant elements can easily destroy the parts you are trying to save. If you try something like this, make sure to place the blob inside a metal baking shell of some sort.
Ah, yes. I forgot to say one needs to select "Hot Air" mode on the oven, rather than just cook it by radiating heat.
RE: The Blob
i too made a blob once when i first got me prusa. mine was PETG though so no hope of separating it. got a whole new carriage assembly.
RE: The Blob
Success! Thanks to everyone for your suggestions. I was able to heat up the hot end very slowly with my bench top power supply.I was able to pull the blob off after it started emanating a very unpleasant smell. The blob also melted part of the PETG parts, and it managed to swallow my thermistor. I'll reprint the PETG parts, and I think I have an extra thermistor somewhere. It won't be long until my Prusa is once again my favorite printer!