I’m having it with the UP300… Anyway, this only happened once, so I kept looking for reasons why I’m printing to air so much. I know I’m not the only one having this problem.
Usually I follow the following procedure after a jam.
- Swap the nozzle to a clean one, and clean the old one in MEK.
- Remove the feed mechanism and clean out the bits of plastic in the gear.
- Change spool to a new one ( happened a lot with older spools. )
Usually when I start to get jams, I will continue to get jams until I do the above. ALL steps.
That last one has me curious. I get more jams with plastic as the spool gets used up. Today something strange happened while printing the raft. I pulled on the straw that guides the filament, and it resisted for a moment as if stuck, then came loose just as the printer jammed. This meant something is binding between the filament guide and the spool. I’ve been hearing a bit of noise from the filament compartment too at times - not loud, but the odd sound that sounds like something just jumped.
And I had a “Eureka” moment. I pulled out the filament and ran it on a pipe between two boxes without taking any action to clear the jam other than pushing the filament down a little into the head while extruding to get it going again.
So I designed and printed up a new spool holder that is within a millimeter of the ID of the spool all around, and just slots in after the spool ( eg, I put the spool in, put in the new axle which has two keys that fit through the slots, and turn it 90 degrees to lock it in place. )
Now the spool moves slowly and very steady while feeding at any speed, and I can visible see it turning without any problems and it’s as smooth as a second hand of a watch. No more jams for the rest of the day, even without cleaning the head.
Now it’s a bit early to say that this was the problem - I’ve had this with all spools, including Tiertime UP spools, especially as they get low. The only spool I didn’t have jams with was an aftermarket one that sat well on the holder… So I’m thinking maybe the spool holder is the reason I’ve been having so many problems to date. Anyway, so far so good. Straight back to printing, with the same spool and without cleaning out the bits of plastic in the gear drive, and it’s still going strong after 1/2 a day of continuous print.
So if anyone else has this feed problem, this is what I’m currently thinking it might be.