How to fix a clogged nozzle

Custom acid etched stainless steel rod....

 

Since im still waiting for the robo, I can advise how I've unclogged my wade with a .35mm. I use abs so I heat the extruder to 250 to make sure its good and soft. Try extruding in increments of 2 mm. If stull clogged after a few times, then remove the nozzle while its still hot. With nozzle removed, and still hot, extrude the full filament diameter glob. Extrude 30mm or so till the filament runs out smooth. This runs any gunk outta the hot area. Let the nozzle cool and clear out as much hardened abs with a 1/16 " bit at the slowest speed on your dremel or drill. Take care not to remove nozzle metal. The bit wont clear the .35 opening so soak the nozzle for at least 3 hours in acetone. Now dig out the tip from inside the nozzle. Ive had good results using a sewing needle or the smallest straight pins you can find. Lastly take the sharpest pin and poke through the nozzle from the outside. Repeat soaking and digging as needed.
Now heres one at your own risk....it worked for me.
I use high temp anti-sieze on the threads when instslling the nozzle. I wait till the clogged nozzle cooled to room temp. Then carefully unscrewed the nozzle. I sometimes get lucky and the hardened filament stays hardened and in tact all the way to the nozzle opening. The clog stays with the dangling filament . Woohoo! I then heat and extrude30mm with nozzle off to clear out any thing else that might have got in the way.

Hope this is helpful...

 

does anybody know if acetone will hurt the thermocuple? I'm thinking of disconnecting the power to the head and lowering it into a shot glass full of acetone. Then once its sat for a while run it back up and clean it out with a wire.

 

I was thinking of just lowering it in to the top of the heater block. I checked and PTFE is safe from acetone, and people use acetone on kapton for their beds all the time so I imagine it should be fine. I honestly suspect that the liner has gotten damaged somehow, but I want to try cleaning it without disassembling it first to hopefully save myself some hastle

Edit: I did try this. I only lowered it up to the bottom of the heater cartridge. It seemed to work fine and now it seems to be printing again.