Major extruding issue on newly assembled kit  

Re: Major extruding issue on newly assembled kit

Go back to basics and print one of the pre-sliced models from the SD card.

Peter

Re: Major extruding issue on newly assembled kit

I managed to print the logo with minor issues - https://imgur.com/gallery/N9fa0
Printing PLA_Buddy_150um_2H now...

Re: Major extruding issue on newly assembled kit

Well it finished... Even tho it is not perfect but it did not fail... I am completely lost now...

Re: Major extruding issue on newly assembled kit

Well, that's better, but it looks as though you had a blockage ner to the end and then a partial recovery.

It's probably worth you taking out the PTFE tubing and replacing it, making sure it's pushed firmly down as you lock it in place.

Better still, undo the heat break half a turn, lock the PTFE tube and then tighten the heat break.

While the PTFE tube is out of the printer, you could also chamfer the lower end slightly to match the heat break seat and remove any burrs fromt he lower end before replacing.

Peter

Re: Major extruding issue on newly assembled kit

Just got a similar problem on my machine which is 3 weeks old. Extruder simply stop extruding, and then motor start and grind out the filament.
Everything goes well before that with PLA or ABS.
At begining I thougt it was the tension given by the spool holder - right or wrong, I don't know ?
My last print in PLA was ok, but I maintain nozzles temperature at 215°C during all printing.
Except this issue, printing quality is good.

Previous message advice to replace the PTFE tubing, does that mean it will be necessary to dismountle the print head every 3 weeks or it was an issue coming from the PTFE tubing ??

Pascal.

Re: Major extruding issue on newly assembled kit

Before I upgraded to the MMU kit, I changed the PTFE only once.

and I had to re configure the new PTfE in the MMU upgrade as soon as I got it... taper the inside of the top taper the inside of the bottom and chamfer the outside of the bottom... (last week)

I have lost count of the number of reels of filament that I have used so far. so this is not a particularly regular occurrance

If you use abrasive filaments a lot, you may wear out more PTFE tubes and nozzles too...

Best wishes, with your new printer.

regards Joan

Re: Major extruding issue on newly assembled kit

I am also having this issue with my new printer. Has happened on multiple spools/brands of PLA. Flow from nozzle stops and extruder motor starts skipping/grinding on the stuck filament. Cleaning nozzle with accupuncture needle has no effect. Can't unload filament which makes me think that the heat sink is getting too hot and the filament is expanding in the ptfe and getting stuck. I've taken the extruder out twice now and both times had to warm the heatsink up with a heatgun to get the filament out once it was unscrewed from the hotend. Once that is cleared and reassembled it extrudes fine again... for a while.

This seems to occur after about 2-2.5 hrs into a print. Heatsink fan is running 100% and has no broken fan blades and airflow is oriented correctly. Baffled as to the reason the heat is creeping up so much into the heatsink.

Re: Major extruding issue on newly assembled kit

I am also having this issue with my new printer. Has happened on multiple spools/brands of PLA. Flow from nozzle stops and extruder motor starts skipping/grinding on the stuck filament. Cleaning nozzle with accupuncture needle has no effect. Can't unload filament which makes me think that the heat sink is getting too hot and the filament is expanding in the ptfe and getting stuck. I've taken the extruder out twice now and both times had to warm the heatsink up with a heatgun to get the filament out once it was unscrewed from the hotend. Once that is cleared and reassembled it extrudes fine again... for a while.

This seems to occur after about 2-2.5 hrs into a print. Heatsink fan is running 100% and has no broken fan blades and airflow is oriented correctly. Baffled as to the reason the heat is creeping up so much into the heatsink.

Have you found a solution to this I am having the exact same problem. Mine may also have to do with a broken/missing embedded Bowden coupler.

Re: Major extruding issue on newly assembled kit

I am also having this issue with my new printer. Has happened on multiple spools/brands of PLA. Flow from nozzle stops and extruder motor starts skipping/grinding on the stuck filament. Cleaning nozzle with accupuncture needle has no effect. Can't unload filament which makes me think that the heat sink is getting too hot and the filament is expanding in the ptfe and getting stuck. I've taken the extruder out twice now and both times had to warm the heatsink up with a heatgun to get the filament out once it was unscrewed from the hotend. Once that is cleared and reassembled it extrudes fine again... for a while.

This seems to occur after about 2-2.5 hrs into a print. Heatsink fan is running 100% and has no broken fan blades and airflow is oriented correctly. Baffled as to the reason the heat is creeping up so much into the heatsink.

I've started getting this problem now also on my 3 week old kit, but so far only with PLA.
I can print PETG and NinjaFlex just fine.

I've tried with PLA from Devil Design, and the silver PLA that came with the printer.

It first started happening when I tried to slice a model using the 0.35 "Fast" setting in Slic3r, and put it down to it simply not being able to handle the higher extrusion rate. But then it started happening with all layer heights, and with most settings I've tried (different temperatures 210-235c, speeds etc. etc.). Also with the pre-sliced models on the SD card.
But after printing for a while the extruder starts skipping, and the filament gets stuck. Then I have to increase the temperature to be able to either pull the filament out, or just push it through.

I've also done several cold pulls, and poked the nozzle with the needles. But they seem to be fine? I can't see any leftovers stuck to the filament.
After re-loading the filament it can extrude at very high speeds (doing the "load filament" a seconds time when the extruder runs very fast in the beginning. And the filament comes out fast and stable).

But, after printing a few layers the extruder starts skipping with that clonking noise.

Yesterday I tried printing the 0.1 Gear on the SD card.
The first time with Devil Design PLA and it managed to print around 50% before it started "air printing".
The second time I tried with the silver PLA that comes with the printer, and it managed the first layer before skipping. I tried increasing the heat a bit, and lower the speed to 60% but it had no effect on it.

Re: Major extruding issue on newly assembled kit

I'm having similar issues. I've had the printer for about a week and have been really happy with the print quality. Then for no apparent reason, it just stopped printing towards the end of a large build. I did some basic troubleshooting and saw nothing wrong, but did notice some buildup of filament dust on the extruder motor gear, so I unloaded the filament and cleaned out the area.

I loaded new filament and it came out looking very nice - thing, constant flow of plastic so everything seemed fine. I printed a small sample from the SD card (whistle) and it looked fine so I thought the gear just needed a little cleaning and was good to go.

Well, i printed a second whistle just to be safe and about midway through it started skipping pretty badly. All the symptoms are as above - if I load fresh filament it works for a bit then fails, with the same skipping issues on the extruder gear. I'm really at a loss as to what could cause this when it was working so well. It seems unlikely to me (though I could obviously be wrong) that the nozzle is clogged, because it prints just fine for a time after reloading the filament. I would think if there was a clog, then loading new filament wouldn't solve that issue.

Re: Major extruding issue on newly assembled kit

Is your printer in an enclosure?

If so, it is getting too warm to cool the heat-break and causing a clog. Try it with the door open.

If not, what is the ambient temperature in your room?

Re: Major extruding issue on newly assembled kit

It's not in an enclosure. The ambient temp is about 74F. (Though that's the same temp for the entire time, so I wouldn't think that's the issue?). i did verify that the fans are still working without issue and ran the self test again (which passed).

Re: Major extruding issue on newly assembled kit

The other thing to check, for changes in behavior at different Z values is to see if you have an intermittent connection in your cable bundle. At different flexes the connection can become sporadic causing issues like this, but only at certain bend values.

Things to look for: Does the temperature swing wildly at those Z values, or when you wiggle the cable bundle?

When it starts to skip, is the extruder still moving?

Typical causes is a crimp in a wire due to routing or excessive zip tie tightening.

Other possible causes are that the filament is not free to unroll from the spool - or the spool itself is binding. Make sure both are free to move.

The last thing to check is if your tension springs are set correctly. I have mine set at 14mm from the body with NO filament in the extruder. This is looser than is intuitive to me, but tighter or looser causes issues. It could be that it works for a while then you get to a thicker or thinner section of filament and it stops.

Also checkt that the grub pulley on the extruder is attached to the extruder with the small grub screw. It can come loose and let the grub pulley slip during printing.

Re: Major extruding issue on newly assembled kit

I looked at all the items below -the spool is not bound, the temperature is pretty stable (generally fluctuates slightly between 208-212 with the setting at 210 and this is consistent with behavior since day one. BTW I'm printing with PLA).

The extruder is attempting to move, what happens is the gear bounces back (best I can describe it) - it attempts to feed the filament but the force required appears too great so it skips. I verified that the gear is not spinning on the motor arm. (The same behavior can be observed by attempting to load filament when the filament is already loaded - when the motor tries to move quickly at the beginning it will skip as it can't force filament that quickly since it's already loaded).

I tried all sorts of positions, manually moving cables, etc. and it doesn't seem to be position related - it seems much related to time in operation (so I'm thinking heat or some type of clog).

To help determine if this is heat related, I setup a fan right next to the printer, blowing across the hotend. This did't seem to make any difference at all.

What's odd (at least to me) is that if I let the printer cool down, then preheat and load a new filament, it comes out very clean and even - no issues at all. I would think that if there were some clogging going on, this wouldn't be the case. I also tried the cold pull technique multiple times and never had any signs of debris or clogging from that either.

I read the instructions on using the acupuncture needle to clean out the nozzle, but I can't seem to find the needle anywhere in my kit. I haven't thrown anything away yet, so if it came with the kit I would have it. Do you happen to recall where the needle was stored? (The forum indicates a needle was included with the kit, I just can't locate one).

Thanks,

Ron

Re: Major extruding issue on newly assembled kit

.........
I read the instructions on using the acupuncture needle to clean out the nozzle, but I can't seem to find the needle anywhere in my kit. I haven't thrown anything away yet, so if it came with the kit I would have it. Do you happen to recall where the needle was stored? (The forum indicates a needle was included with the kit, I just can't locate one).

Thanks,

Ron

If I recall correctly, the needle came in the same tiny bag as the alcohol wipes.