Hotend jams after a while during printing

Hi, 

I am trying to print a pretty large print: 200mmx100mmx50mm.

With the 0.29 resolution it takes about 12 hours, but after maybe one or two hours the hotend jams.

I guess the printer have printed maybe 10-20 layers that are fine but then just suddenly jams. 

I have leveled the bed and are printing with a IKEA-bag over to prevent warping. 

As the print takes such long time I cant oversee the print and I cant figure out what the problem is. With a gentle push on the filament the hotend starts extruding again.

Anyone that have experienced the same problem and have some tips on what to do to prevent this?

Regards,

Snake

Try printing with the front end and top open, just cover the sides.

I'm guessing the filament is getting too hot inside the tube and the extruder gear can't grab it.. How hot is the block for the X-Y axis?

That's what I think is happening Kyle, that is what I suggested opening the top and front of the extruder

Tried printing today again with just the sides covered and recalibrated the heatbed. The result was even worse today.

At random spots it stopped extrude and by gently pushing the filament it started again. So I think the filament might be the problem.

I haven't got the precision tools to measure the thickness at a fair level but will try another spool later today. 

Thank you for your answers!

I agree with Kyle and Richdon, inside the printer temp. was too hot and that's why filament was jammed. Top and front should be open or should have some holes for ventilation. We are currently preparing the draft of panels for housing.

BR,

Rafal

Rafal - I can't wait to see what you guys come up with for the panels!

Tried printing today again with just the sides covered and recalibrated the heatbed. The result was even worse today.

At random spots it stopped extrude and by gently pushing the filament it started again. So I think the filament might be the problem.

I haven't got the precision tools to measure the thickness at a fair level but will try another spool later today. 

Thank you for your answers!

It's possible that the extra heat cause some issues with the connector that goes from the board to the stepper motor, in the top just behind where the filament loads. If so I noticed that with a loose connection mine sometimes oscillates back and forward. If it stops feeding relatively in the same locations in the xy directions then it is a very good possibility there is a loose connection. I am currently having the same issue, I think I have worked mine out but I am not sure. 

I posted it somewhere else. and Winstonc also posted a youtube video, in the same thread, of what both his and mine was doing.

When you say random spot it sounds to me like a loose connection, and if it is in the same xy plane then it sounds even more like a loose connection.

It's possible that the extra heat cause some issues with the connector that goes from the board to the stepper motor, in the top just behind where the filament loads. If so I noticed that with a loose connection mine sometimes oscillates back and forward. If it stops feeding relatively in the same locations in the xy directions then it is a very good possibility there is a loose connection. I am currently having the same issue, I think I have worked mine out but I am not sure. 

I posted it somewhere else. and Winstonc also posted a youtube video, in the same thread, of what both his and mine was doing.

When you say random spot it sounds to me like a loose connection, and if it is in the same xy plane then it sounds even more like a loose connection.

It's not a loose connection since the extruder stepper continues to rotate. Tried another spool and realized that there must have been som dust in the nozzle that made it clog a bit just enough to make some filament come through now and then. The nozzle is lying in a bath of actone right now. Let's hope that this works!

Was it rotating or moving back and forwards. Because mine was doing something similar and I thought clogged nozzle.

Then I took the nozzle off and connected a 7/32 x 1 1/2" spring to the place where the nozzle goes, and started a print. when the spring touch the bed it calibrated itself 1 1/2" high with no nozzle. Even with no nozzle and the stepper motor was still "clogging" in reality it just was getting intermitent power.

Hopefully yours is just a nozzle though, just keep that in mind.

Still having problems with this. I took the nozzle off and put it in acetone over night and used a guitarstring to make sure the hole wasnt clogged. Assembled it again but it still does not work. I have tried to feed filament without the nozzle and it works great. Really confused about where the problem might be.

This is how it looked after the acetone cleaning.

k4ft69.jpg

This thing have a pattern. I bet isn't a clog.

Right before the print starts, Pull off that string of plastic hanging from nozzle with the tweezers. It may not be making a connection right away causing the Z-0 to be off a little. This puts the nozzle too close to the bed. Makes it hard for extruder to push plastic out. The nozzle should just kiss the platform on calibration, not push down too far on it. Just take a look and see how it acts.

This thing have a pattern. I bet isn't a clog.

Morris code for "SOS" perhaps.

I agree with Kyle and Richdon, inside the printer temp. was too hot and that's why filament was jammed. Top and front should be open or should have some holes for ventilation. We are currently preparing the draft of panels for housing.

BR,

Rafal

When should we expect side panels in z-store?

Just been picky, I think it isn't a platform problem. You can see four "white" diagonals draw by the failed raft. This is a regular, a pattern fail. Like if the spool was touching something when rotating, having friction. (apologize the horrible English, I'm a little bit tired, can't explain clearly what I'm thinking)

sorry...

One thing you might want to try …

If you have had a slipping problem with the extruder gear, it will have ended up filling the gear with ground up ABS … So then you probably removed or loosened the stepper to clean the gear out ?

Here’s what I discovered …

Despite the screws that secure the strepper having countersunk holes to go into, they don’t actually centre correctly. If you simply screw them back in tight you will find that the gear doesn’t squash the filament well against the small bearing.

The cure is to tighten the stepper back up whilst pushing the assembly to the right - ensuring that it minimises the gap for the filament resulting in a MASSIVE reduction in extruding problems.

Mine was doing exactly the same as yours. Incidentally I ended up actually replacing the countersunk screws with proper hex cap stainless screws as the originals were about as hard as cheese lol. I did send Zortrax a complete report so they are already aware of the affect that this misalignment causes producing the result like you have. It’s so simple to resolve once you know what it is though. Also make sure that the larger cavity behind the main 0.4mm bore is also cleaned right out in the nozzle - it’s easy to miss that the cavity is even there.

Cheers,

Jay

Looks to me that your tip is partially plugged I had the same issue while back I took the tip off soaked it in acetone overnight and put it back problem cleared up

One thing you might want to try .....

If you have had a slipping problem with the extruder gear, it will have ended up filling the gear with ground up ABS … So then you probably removed or loosened the stepper to clean the gear out ?

Here’s what I discovered …

Despite the screws that secure the strepper having countersunk holes to go into, they don’t actually centre correctly. If you simply screw them back in tight you will find that the gear doesn’t squash the filament well against the small bearing.

The cure is to tighten the stepper back up whilst pushing the assembly to the right - ensuring that it minimises the gap for the filament resulting in a MASSIVE reduction in extruding problems.

Mine was doing exactly the same as yours. Incidentally I ended up actually replacing the countersunk screws with proper hex cap stainless screws as the originals were about as hard as cheese lol. I did send Zortrax a complete report so they are already aware of the affect that this misalignment causes producing the result like you have. It’s so simple to resolve once you know what it is though. Also make sure that the larger cavity behind the main 0.4mm bore is also cleaned right out in the nozzle - it’s easy to miss that the cavity is even there.

Cheers,

Jay

I had to do the exact same thing recently Jaycee.

One thing you might want to try .....

If you have had a slipping problem with the extruder gear, it will have ended up filling the gear with ground up ABS … So then you probably removed or loosened the stepper to clean the gear out ?

Here’s what I discovered …

Despite the screws that secure the strepper having countersunk holes to go into, they don’t actually centre correctly. If you simply screw them back in tight you will find that the gear doesn’t squash the filament well against the small bearing.

The cure is to tighten the stepper back up whilst pushing the assembly to the right - ensuring that it minimises the gap for the filament resulting in a MASSIVE reduction in extruding problems.

Mine was doing exactly the same as yours. Incidentally I ended up actually replacing the countersunk screws with proper hex cap stainless screws as the originals were about as hard as cheese lol. I did send Zortrax a complete report so they are already aware of the affect that this misalignment causes producing the result like you have. It’s so simple to resolve once you know what it is though. Also make sure that the larger cavity behind the main 0.4mm bore is also cleaned right out in the nozzle - it’s easy to miss that the cavity is even there.

Cheers,

Jay

Thank you Jay, this seemed to be the problem. I am currently printing again and the raft looks ok now. 

Hope that this works!