PETG keeps jamming. I’m printing slow, 235C, e3d v6 hotend. After it runs for a little while, it jams.
All I do to fix it is set the temp, pull out the filament and cut out where it ground it down, then push it back in. I have no idea what’s causing this to happen.
Try 245-260
In my experience this seems to be (mostly) related to retraction. How aggressive are your retract settings?
Worried that will impede bridging. Also doesn’t make sense that it works for 30min to an hour, then suddenly stops.
Try increasing your Temps 5c at a time.
It sounds like heat creep.
Manufacturer? I am printing ESUN at 250 for the first few layers then dropping it to 240 for the rest. No heat bed.
Are you using a heat bed? Perhaps it is keeping the hotend warmer at the start, keeping the flow going. But after 30-60 minutes, you are to far from the bed for it to benefit.
Yeah, that’s almost exactly what I see with weird PETG jams too. If it jams somewhere once, there’s also a good chance it will jam there every single other time as well, the jams are repeatable.
I’m convinced it’s related to retract settings though, PETG seems to swell significantly when heated, and frequent long retracts will pull already expanded filament farther up into the barrel until it jams. If I hear it happen quickly enough I can pause the print, move it clear of the object, then extrude a few hundred millimeters (giving the extruder some manual assistance at first) and restart and it will be fine usually through to the end.
3mm retraction. I thought it might be heat creep to, so I’m trying to print a 40mm fan bracket. I also just put a little oil in my filament cleaning sponge, that should help with heat creep.
Replace ptfe tube, ensure good mating, round the side that is facing hot end, ensure pfte tube is not loose (tighten collar). Use original e3d fan+duct.
Heatcreap maybe. Have that at low speeds too. The filament flattens under the tensionbearing in the extruder than…
Is it possible that the idler tension is too high?
Because PETG is soft compared to PLA and ABS, maybe after the extruder motor shaft heats up, the gear could start to cut into the filament or squash it if the tensioner is set too tight.
Definately lower your retraction, as long as you are not getting blobs, you are good to go lower. I was getting alot of jams due to a long retraction setting.
I agree with +Ray Kholodovsky at higher speeds I go at high as 265C on some brands of PETG. But at slower speeds around 250C should do.
On my printer with a roughly 300mm long bowden tube I have to turn my retraction all the way down to 1.45mm. And I still get this same sort of jam on particularly small parts with quick layers or lots of retracts. At that point I get lots of stringing, but it does make the print run quite a bit better in most situations (although sadly not all).
PETG is surprisingly headachey as a material.
@Stephen_Baird but the headaches are worth it in the end.
PETG printed parts are really good at accepting abuse without falling to pieces.
Oh yeah, once you get the extrusion issues worked out PETG is wonderful. Virtually no warp during printing, tough parts that will deform slightly rather than snap but that can take high heat. It’s a good combination of PLA and ABS features… it’s just so frustrating when it does its jamming trick.
I think it’s heat creep too… we print almost exclusively with PETG and it’s really fantastic BUT we got rid of all our old extruders and now ONLY use the Bondtech.se kits… no more slipping or grinding… now we print PLA at 185degrees… though PETG is only 225deg…
3mm retraction on a direct drive setup might cause you some issues. Try 245c and 2mm retraction
I used to get what I thought were jams but seemed more like the temperature was just too low so it’d print fine for the first layer which was slow and then the later layers would speed up and the heater couldn’t melt the filament fast enough.
Now I print it at 240 degrees, around 45mm/s and have used up to 8mm of retraction (bowden) with zero jamming issues. Previously I was at 230 - 235 degrees to help reduce the terrible stringing I was getting with one particular brand.