Dissolve PLA from Hot end....

I had a mishap last night, after I set a job to print; probably 30 mins after I went to bed it all went hay wire. I had filament all over the place, the glass bed was ashew and the extruder was loose on its mount. To complete this nightmare the hot-end/ block assembly is covered with PLA. I use an E3DV6 (or I was - now I'm using my Back up E3DV6-Lite). I wanted to simply heat up the hot-end and hold it with pliers and scrap it off, but the thermister is damaged and the machine just displays a "Max Temp" or "Min Temp" Error. At this point I just want to salvage the block, nozzle and Heater Cartridge. Today I learned what the "Pretty Blue E3D Rubber Thing" is... a silicone sock :rolleyes:. Funny when I put the Hot-end together I didn't see it mentioned (even this morning when I was installing my back-up) Not to say it not on the Wiki, I just missed it somehow. I thought its was a storage holder of some sort, now I know better....

But the point of this post is what can i use to dissolve PLA - and preferably salvage parts that still work. Thanks

This guy has done some research in that area: http://www.vinland.com/blog/?p=68

It is the methylene-chloride (dichloromethane) in the Weld#5 mix that does the trick. In labs we use it to dissolve PLA. Chloroform (trichloromethane) will also work.

They are both nasty stuff however, like all solvents that will dissolve PLA. See: https://www.sciencelab.com/msds.php?msdsId=9926060 and https://www.sciencelab.com/msds.php?msdsId=9927133

IF you want to go that way, use disposable gloves, don't get it on your skin, don't inhale the fumes. Do it outside and please dispose of the used solvent in a responsible way. If you know someone who has access to a proper lab, ask him/her to help.

wow - I don't think I'd use any of that stuff outside of a proper fume cupboard.
Good luck - sounds like you need it !

Luck is not what you need, just some common sense...

Actually, lots of people use chloroform to glue perspex parts together, both amateurs and professionals. Just do it in a well ventilated area. Chloroform was quite popular as an anesthetic until after WW2, so do not breath the fumes too much and keep it from your skin.

I use MEK - methyl ethyl ketone - you will need ventilation as well but it is better than chloroform.

A picture would help portray how bad of a situation you have.

Before going the chemical route, I'd set the hot end on piece of plywood and use a hot air gun to warm up the PLA so it can be peeled away using something like wood craft/popsicle sticks with the end cut square. Take your time - the thicker the PLA is, the longer the time needed to get all of the PLA soft. Some have used a blow torch for issues like this, but IMO it's too easy to overdo the heat with a torch.

BTW - the e3dV6 rubber boot thing is fairly new. There's a lot of e3dv6 documentation out there that doesn't mention it.

Wow thanks for all the tips the link to the methods the guy used was interesting. The hot gun idea sounds lengthy but promising, I may avoid the chemical route after I think about it (I didn't expect to soak it for hours) because I'm unsure of what effect it will have on the Heater Cartridge and its wire coating. I do have a soldering gun (heavy duty soldering iron) that has special attachments maybe I can clamp the block it to the tip....

BTW - In case you want to try using the printer to heat up the hot end, MINTEMP error means the thermistor is open or there is a break in the wiring connection to it. MAXTEMP error means there's a short.

Good luck.

why not use the soldering gun on low and use that to melt and cut the pla off ?

I don't know about a low setting, my soldering gun doesn't have a variable heat setting, but yea that might be the way to go, their so much PLA coating the block I can't remove screw holding the heater cartridge. once I get it out then I'll soak it in some paint thinner / turpentine to clean of the block and nozzle. I'm not keen on soaking it in a flammable liquid with the heater cartridge still in it as I have a fear the wire coating will absorb it and then (I'm sure I'm probably wrong through) down the road when I decide the put it on the system it burst into flames when I try a print.

Well figured I'd follow up, the soldering iron was a no-go I couldn't get the heater block hot enough to remove the screw holding the heater cartridge in. I decided to connect the heater cartridge back into the printer control board, but left the thermister connected to the hot mounted to the printer, turned on the printer and set it to heat up the "nozzle" to 220, verified it was working with a laser thermometer. When it got hot enough I was able to remove the screw holding the heater cartridge, the damaged thermister, nozzle and a part if the heat sink that was stuck there as well. tomorrow I'll soak it in paint thinner to clean off what I can and then put it back in the printer.
Thanks for all the suggestions.