atomic method stuck PLA difficult to remove

[howardsmith 0]

I've previously used the atomic method with success but I'm coming into some problems this time around. When pushing material in at first a lump of molten plastic dropped out of the extruder head onto the plate but on cooling the nozzle to 90 degrees I can't pull the pla out like I have previously. It seems to be jammed pretty good and I'm worried pulling to sharp and hard will cause more problems than it solves. I've had to reheat to get out the plastic but looking through the nozzle at the top I can see it's still blocked (though pushing plastic through it does come out).

 

[zoev89 73]

Don't know if it will work for you... You can try to pull it at a higher temperature to see if you can get something out. Sometimes I also need to pull at 100 or 110 degrees since at 90 it is stuck to hard. I also had 1 time that I pulled and it got itself completely stuck I needed to heat-up the cooler section of my hotend to get it out. If worst comes to worst you need to take the hotend out and burn the residue to get it out, but only do that once it is hopeless.

 

[IRobertI 521]

If you position the head in a corner so that you don't risk bending any of the axes I don't think you can do much damage really. If you pull hard enough you will lift the nozzle (it will compress the spring).

Try a slightly higher temp like Zoev89 suggested to get it as clean as possible. Then I would take the head apart and check that no plastic has leaked out between the PTFE and the top of the heater block. It's unlikely but if you've been pulling on things hard (that sounds dirty...) it could happen. This will also give you a chance to inspect the PTFE for damage. If you've been printing for a while (especially if you've been printing hot) it might be time for a replacement.

The PTFE tends to deform at the exit but in addition to that, a ring formed depression is formed on the inside of it a few millimeters from the exit. If that depression is big enough the PLA might expand into it and get locked in place as it cools.

 

[howardsmith 0]

After switching it off and letting it cool down I tried again and it worked this time. Panicked for a minute there, but good to know you can pull on it a bit. I did try pulling at higher temperatures but what happened was I had to keep going higher until it got to the point it came out in a thin strand.

I've not had it be this difficult before, and the blobs of PLA that exited from the nozzle came out quite waxy with a different finish to them. I've not used anything other than PLA so I thought that was odd.