Extrusion problem after not printing for 2-3 days

[Ryan8696 1]

Hi everyone,

 

I've found that if I load my filament and then I print the printer extrudes ok. 

However once I leave my printer for 2-3 days without printing and then print the printer doesn't extrude any filament.

I then have to unload the filament - load it again and then I can print again.

Is there a way to avoid having to do this before each print?

[Smithy 1,146]

I had the same problem today twice. Today in the morning (last print was yesterday afternoon) and again in the evening today, after loading a new filament. Filement was coming out after loading, then startet a print job but without a filament.

 

I fixed it both times with unload/load, but thats annoying....

 

BR Christian

[fbrc8-erin 302]

What material are you printing with?

What printer are you using?

 

Are you slicing with Cura?

 

When you remove the filament to unload it, is it damaged near the feeder?

[Ryan8696 1]

Hi Erin - thanks for your help - I've just been using load/unload but that is a bit of a pain.

 

My printer is a UM3E - printing with UM PVA AND PLA (it happens with both nozzles) & using Cura.

 

When i withdraw the filament there is no damage to it etc.

[fbrc8-erin 302]

At the end of a print, it should withdraw the filament a little (not leave it all the way in the nozzle), but during the purging for the next print, it should move it forward far enough to start extruding again. If there's no damage to the filament it should just go ahead and work fine on the next print without needing to be unloaded and reloaded.

[Ryan8696 1]

Hi Erin, unfortunately i'm still having this issue even after waiting for the purge to finish after each print. Any other ideas?

[fbrc8-erin 302]

There shouldn't be anything about the filament the really changes over a couple of days when it's not running. Is it brittle? 

[Ryan8696 1]

Nope - It's only about a week old and i've had it in a dry box the entire time...

[fbrc8-erin 302]

I've seen soft filament (like TPU) dent if left at rest in the feeder for a couple of days, but you shouldn't be seeing anything like that with PLA. If it was a UM2+ I might think the bowden tube wasn't seated all the way and caused swelling, but the UM3 bowden tubes are almost impossible to seat wrong.

The only other thing I can think of: is your front fan running?

[kmanstudios 1,120]

One thing I have done just to make sure things are doing well is to do a filament move before printing. Mostly for the PVA if it has been inactive in printing. Moisture can still get to the filament and it may have softened or clogged a bit, so I set the temp a bit higher than normal (say 5 or ten degrees) and then go to the move commands. This way it will make sure it is a bit softer when starting out, will not fry the filament in the nozzle and let me see how things are moving.

 

I can also tell by what color it is if it has cooked a bit.

 

But the best thing about the move is that it will give me a good idea of what is happening before I hit print.

[Ryan8696 1]

Thanks @kmanstudios, I actually have tried the filament move command and that has worked - the only question I have is how much do you actually move it? if I don't move it enough no filament comes out - if I move it too much when the nozzle heats up for the active leveling before the print the filament "leaks" out of the nozzle which makes the active leveling fail.

 

Or are saying that i should not move it at all and simply heat the nozzle above the standard temp for a few minutes before printing?

[kmanstudios 1,120]

I move my filament until I am sure it is extruding well. Then I back it off a slight bit just to help it not leak out during active leveling. And, I use needle nose pliers for a few minutes just to catch anything that is melting out before it cools. This is also a good time to clean the nozzles a bit because it also softens the gunk on the outside that can cause other issues such as a leveling error and such.

 

And once you are actually just up and running and not having to test your flow, I heat both my nozzles before printing to about 150¯C for the purpose of cleaning the nozzles. Just enough to soften the gunk and not fry the materials inside them.

[Ryan8696 1]

Thats great - i will try your tips. Thank  you so much for taking the time to help - I really appreciated it!!

 

 

[kmanstudios 1,120]

you are quite welcome. :)