Filament snapping/breaking in only one of the five extruders  

RE: Filament snapping/breaking in only one of the five extruders

The old v6 hotend had a straight through filament path with extruder gears on each side.

The Nextruder curves the filament along the large gear and a couple idlers. No longer a straight and simple path so making sure your filament is not brittle has changed from "should" to "must." Otherwise the filament has a greater chance to snap at the extruder gear, as you've pictured, if not in the ptfe pathing like some have experienced.

Keep your filament out of the sun (UV exposure), don't leave it in the PTFE tubes if you're not actively printing, store it in a dry space, dehydrate your spools before usage.

RE: Filament snapping/breaking in only one of the five extruders

Thanks for the tip! I have been drying the filament more recently. You also reminded me that a new spool, despite its vacuum package, does age and does require drying if left in stock for a while.

Appreciate the time you have taken to respond.

Cheers!

RE: Filament snapping/breaking in only one of the five extruders

Posted by: @bartgalok

 

Hi Everyone,

I am flummoxed. I have a five-extruder XL. It has been working extremely well with firmware 5.12 and PrusaSlicer 2.7.1 until now. 

One of the extruders (#4) will push through filament without issue and then for no reason the filament will break within the planetary gear chamber. The idler screws are set appropriately. It loads filament without issue. I have used brand new Filamentum PLA filament and dehydrated eSUN  PLA filament with the same results. I changed the Nozzle to a new one. Still no difference. Using the same filament in the other extruders does not produce the problem.

Nozzle Temp is set to 205C. Nozzle size is 0.6 mm.

Nozzle was not jammed. Able to remove lower filament segment.

I am using the stock settings and changed only the retraction length to 1 mm.

I have no clue what to do next. or what I should adjust. Is it the shearing force of the retraction during fine small print deposits where retraction frequency may be increased? Does adjusting the idler screws make a difference? Is it the gear that is cutting the filament. Do I reduce or increase the tension of the screws? Is there too much slack between the gear and the rollers? There are the usual gear marks on the filament.

I did not change the setting as received from the factory.

Has anyone had this issue?

Very frustrating.

Thanks for your assistance.

 

Out of interest... How do you clear it once it's broken at that point? Mine did that this morning and I've been trying to clear it ever since.

RE: Filament snapping/breaking in only one of the five extruders

Heat up the nozzle and see if you can pull it out with some needle pliers, or just push it through with filament and extruder movement (like any normal filament purge). Otherwise, you may have to remove nozzle from the extruder and heatgun (or something) to poke/melt/remove it.