I'm at my wits ends here. it's about 50/50 if a print will finish successfully anymore (not an exaggeration) I am constantly getting jams with the esun clear PETg on my V3B. The jam seems to be post filament drive, immediately after the gear. there is always a worm of filament jammed up in the drive when I disassemble. some stats that i think might be useful and my thoughts.
Stock filament drive (tried my own PETG drive but it jammed as well.)
V3B heater at 250C (I don't think this is too hot, am I right?)
printing at sub 60mm/s speeds (and that's for infill)
Filament Dia 1.715 and multi at 1.00 (yes) (not that I think these number relate to jamming but, hey...)
40mm Noctua Fan.
I'm to the point of desperation here, these jams are really dragging on my love of 3D printing, where I don't even want to get into it at risk of wasting time and plastic due to a jam...
HALP!
Constant PETg jams.
Re: Constant PETg jams.
Is the worm oval in shape, or is it round? If it's flattened or oval shaped, then your tension is too high on the filament drive screw. (It can cause jamming.)
If it's not that, the only other thing i can think of is that the Noctua fan might be cooling off the extruder too much.
If it's not that, the only other thing i can think of is that the Noctua fan might be cooling off the extruder too much.
Re: Constant PETg jams.
Yes, try turning off the fan. I can't run fan for PETG. Also try going even slower. Go down to 40 mm/s, then crank it up once you are comfortable that you're not going to jam.
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Matt_Sharkey
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Re: Constant PETg jams.
the worm is in the trash can. I have used the finger tight method on the tension screw with mixed results but not enough to say thats an issue. I feel that when these things happen I try to fix it in an ad hoc method and not empirically which is biting me in the ass right now.Jules wrote:Is the worm oval in shape, or is it round? If it's flattened or oval shaped, then your tension is too high on the filament drive screw. (It can cause jamming.)
If it's not that, the only other thing i can think of is that the Noctua fan might be cooling off the extruder too much.
pretty sure that the noctua fan is not causing any more cooling than the stock one (it would be considered a downgrade in that department)
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Matt_Sharkey
- Posts: 347
- Joined: Mon Oct 20, 2014 3:10 pm
Re: Constant PETg jams.
TURN OFF THE FILAMENT DRIVE FAN?jsc wrote:Yes, try turning off the fan. I can't run fan for PETG. Also try going even slower. Go down to 40 mm/s, then crank it up once you are comfortable that you're not going to jam.
seriously?
Re: Constant PETg jams.
Yes. In fact, when I run with my hurricane fan on, the layers just fall apart. You can "fan" them apart with your fingers, haha. Fan is only really beneficial for PLA.
Oh, wait, you mean the upper fan that's cooling the filament drive. No, leave that on, it should be on all the time.
Anyway, try 40 mm/s at 255, light tension on the screw. Then when it works all the time, you can try turning up the speeds.
I tracked down the major source of jamming for PETG to be too high a total extrusion rate. That takes into account your extrusion settings, print speed, and infill extrusion multiplier. If you have the last set higher than 130% (in order to get decent infill) you need to take speeds down. I've found I *can* hit 60 mm/s with 130%, but I've recently just gone to 40 mm/s on all layers with 100% on all speed multipliers, makes for really good quality, and I'm not in that much of a rush.
Oh, wait, you mean the upper fan that's cooling the filament drive. No, leave that on, it should be on all the time.
Anyway, try 40 mm/s at 255, light tension on the screw. Then when it works all the time, you can try turning up the speeds.
I tracked down the major source of jamming for PETG to be too high a total extrusion rate. That takes into account your extrusion settings, print speed, and infill extrusion multiplier. If you have the last set higher than 130% (in order to get decent infill) you need to take speeds down. I've found I *can* hit 60 mm/s with 130%, but I've recently just gone to 40 mm/s on all layers with 100% on all speed multipliers, makes for really good quality, and I'm not in that much of a rush.
Re: Constant PETg jams.
Matt, if you can, dig the end out of the trash and take a look at it after reading this:
viewtopic.php?f=3&t=2694
It really sounds to me like the tension might be too tight, but you're not going to be able to tell without looking at the end. It might be the fan issue as well, but the first thing i always check with PETG is the tension. Too much tension and it jams. It really doesn't take much to hold it, not much more than PLA.
viewtopic.php?f=3&t=2694
It really sounds to me like the tension might be too tight, but you're not going to be able to tell without looking at the end. It might be the fan issue as well, but the first thing i always check with PETG is the tension. Too much tension and it jams. It really doesn't take much to hold it, not much more than PLA.
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Matt_Sharkey
- Posts: 347
- Joined: Mon Oct 20, 2014 3:10 pm
Re: Constant PETg jams.
i switched over to black for now, i put the tension on hand tight, then backed it off a quarter. It's printing okay right now but it's too soon to tell. I'll try to get a print out later this week on the clear to see if tension is the culprit. also trying out JSC's slow and steady method.
As an aside I put all of the extrusion widths to 0.4mm to keep the speed constant. the infill rate isn't impressive, but it seems like consistency is key.
I love all of the physical properties of PETG but, Damn, is it problematic.
As an aside I put all of the extrusion widths to 0.4mm to keep the speed constant. the infill rate isn't impressive, but it seems like consistency is key.
I love all of the physical properties of PETG but, Damn, is it problematic.
Re: Constant PETg jams.
all great info from jules and jin. im going to throw this out there also as another thing to check and im going back a long time here BUT you are using a v3b. the v3b is an older tech type hot end. it has the traditional brass tube, no heat break or ptfe liner. i remember having jams in my v3b about every 15-20 times i changed from one type of plastic to another. problem is the plastic melts in the brass tube, sticks to the wall of it then you do a plastic switchout and the next plastic type does the same thing while not intermixing with the last plastic stuck to the wall. keep doing this and layer by layer the tube gets tighter. it eventually gets so tight that its hard to feed plastic through it. i actually soaked the brass tube one time in my spray gun soaking basket which softened the plastic lining the tube. i slid the soft plastic out and let it reharden up overnight then took an exacto knife and sliced it. you could see the rainbow of layers built up over time. it was like looking at a cross section of 20 different color paintjobs on top of each other. the new v4 or e3dv6 dont have this issue because of the ptfe liner and the heat break making a sharp hot zone. basically in your case its probably not a bad idea to disassemble the hot end and run a 2mm bit down the brass tube and also do a nozzle cleaning. i used to do this as a routine maintenance.
if you dont already have one get yourself a 6" long 2mm drill bit. it really is a must have for a 3d printer owner. run it down the filament drive to make sure that hole is the right size and round. 90% of the time with my e3d if i have a feed problem its too much tension and wont go through the bottom hole of the drive. i almost never have feed issues with any plastic now that i have the e3d and the v4.
if you dont already have one get yourself a 6" long 2mm drill bit. it really is a must have for a 3d printer owner. run it down the filament drive to make sure that hole is the right size and round. 90% of the time with my e3d if i have a feed problem its too much tension and wont go through the bottom hole of the drive. i almost never have feed issues with any plastic now that i have the e3d and the v4.
Re: Constant PETg jams.
Upgrade to the new V4. I know this may not be an option for some price wise at this time or for other reasons. However I cannot state enough how this one upgrade turned my experience with this printer 180 degrees. I got my printer in the fall and lived in a drafty cold house and was always fighting with your problem on any filament. I am not knocking the v3b as it is a time proven and we'll loved hotend. I just never had luck with it. Just my two cents. 