Clicking extruder
It is a while since I have had to take the extruder apart, things seemed to be working fine.
Part way through a print, the extruder drive started clicking, and the print became a mess, so I've had a look at the printer. A search online came up with several suggestions, and I think I've looked at them all.
Just trying to load filament (before starting a print), it was clicking. I've tried adjusting the tension, everything from hardly anything to quite tight (going up a quarter turn at a time), but it makes no difference.
I've taken the idler off the printer, and it appears to be OK, barely a mark on it. I've taken the extruder motor off, and the gear attached to that also appears clean, and there is very little in the way of debris on the inside of the housing. I've also done a cold pull (which came out clean at the first attempt). Having done all that, I'm still getting clicking, so I'm at a loss on what to do next.
Adrian
RE: Clicking extruder
Are you sure the filament supply is running off the spool ok? I had a similar problem and I found that the filament was tying itself into knots.
RE: Clicking extruder
Are you sure the filament supply is running off the spool ok? I had a similar problem and I found that the filament was tying itself into knots.
Thanks for the reply.
My filament is running OK (I've checked several times). I've always been wary of tangles on the drum.
I had another look at it today. I tried it with a different drum of filament, and it still clicks, but when I run the extruder motor with out any filament in it, it runs smoothly, so it looks as though the problem is down to the presence of filament. Watching what happens, the clicking isn't starting as soon as it feed filament through, it seems to be once the end of the filament is some distance down into the hot head, as though there is something there restricting it (the filament does come out of the extruder head), but as I said above, I've done a cold pull, and that came out clean.
Adrian
RE: Clicking extruder
Hi Adrian,
Clicking means slipping gears. Gears slip basically for three reasons.
Upstream problem, meaning trying to pull in filament that is blocked. You are sure that your filament runs freely of the spool, hence this can't be the problem.
Problem with the gears as such, meaning they are unable to properly grab the filament. That happens with either worn or dirty gears or with the wrong idler tension (both too high and too low). You inspected them and they are okay and played around with the idler tension, once again that can't be the problem.
Which leaves us with a downstream problem. And here comes my little story from not too long ago. Had pretty much the same happening to me. Prints started fine and some time in the clicking started. Done about a dozen cold pulls and they all looked ok to me. But I noticed that I had to use way more force to push the filament into the extruder than previously. I measured the extruded filament and it definitely wasn't 0.4mm.
So the trusty acupuncture needle to the rescue. Inserted it in the nicely preheated nozzle and out came a nasty burned looking glob of plastic. Problem free printing again since then.
There must have been a slow build up of gunk in the filament path over time and the cold pulls must have partially cleared the path on every attempt.
If that fails you could try a new nozzle to eliminate it as a possible culprit.
hth
Hansjoerg
RE: Clicking extruder
Hi Adrian,
Which leaves us with a downstream problem. And here comes my little story from not too long ago. Had pretty much the same happening to me. Prints started fine and some time in the clicking started. Done about a dozen cold pulls and they all looked ok to me. But I noticed that I had to use way more force to push the filament into the extruder than previously. I measured the extruded filament and it definitely wasn't 0.4mm.
So the trusty acupuncture needle to the rescue. Inserted it in the nicely preheated nozzle and out came a nasty burned looking glob of plastic. Problem free printing again since then.
There must have been a slow build up of gunk in the filament path over time and the cold pulls must have partially cleared the path on every attempt.
If that fails you could try a new nozzle to eliminate it as a possible culprit.
hth
Hansjoerg
Thanks for the reply.
I was starting to conclude that the problem was at the bottom end, so was planning on doing a strip down on it. I've got another extruder (.25 rather than the usual .4) so I can also give that a try.
Adrian
RE: Clicking extruder
I've had another session on this.
I started off changing the extruder, putting in the .25mm one. The filament went straight through, no clicking. Pretty much confirmed that the problem is with the .4mm extruder.
Once it had cooled down, I (gently) placed it in a vice, and started with a 1.5mm dia drill on the threaded end, and that removed quite a bit of filament. Once that was done, I turned it over, and swapped to a .4mm dia drill and came in from the other end, that removed the residual filament. Once that was gone, holding it up to the light showed it to be clear. I swapped the extruders back over, and the filament load worked without a problem, and my test print (used to fine tune the Z axis) went with out a hitch.
Problem appears to be solved.
Thanks for the suggestions.
Adrian