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Author Topic: Extruder Stalling Problems  (Read 1886 times)

Coco

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Re: Extruder Stalling Problems
« Reply #30 on: November 18, 2013, 03:14:01 AM »
Hi!

I've been having this exact problem with the Diamond Age Sapphire Blue PLA. I tried 190 degrees and then 210, but both attempts had that same problem. I changed filaments and now am doing the same print without any problems.

Thanks!

-Coco

Herb

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Re: Extruder Stalling Problems
« Reply #31 on: November 18, 2013, 04:16:01 AM »
What did you change your filament to? A different batch of PLA from the same supplier? PLA from a different supplier? Or something other than PLA?
Bukobot Duo v2

Zigor

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Re: Extruder Stalling Problems
« Reply #32 on: November 18, 2013, 09:25:32 PM »
I think I found the solution, but I don't want to jump the gun too much...

Soooo... Here's what I did:

Switched drivers (I still believe one to be bad, but I will test it further)

Lowered the barrel so that it's barely sticking out from above the nut.  (Being close to the gear cause the filament to have too much of a corner to push past.  Since the barrel is slightly offset from the gear.)

Printed out the dust collector thing from thingiverse that goes on the filament.  (I'm on my phone, otherwise I'd post the link...) with a little drop of oil that filament slides through like... I don't even know... But it's great.

And modified the bolt hole in the idler lever.

I think there's more... Oh!  But now my stepper motor for the extruder and the one for the x axis get incredibly hot!  Both seem to have the current set at about medium... Do I need to turn that down?
« Last Edit: November 18, 2013, 11:59:23 PM by Zigor »

whosawhatsis

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Re: Extruder Stalling Problems
« Reply #33 on: November 20, 2013, 09:30:54 PM »
Ok, two things I can see from that video. First, you're extruding too fast. Your test extrusions shouldn't be faster than 120mm/s, and that looks like at least 150. Second, you seem to have very smooth extrusion until it suddenly stops completely. This is usually caused by bad filament going out of tolerance If it gets too thick, it can jam in the stainless steel barrel. It should always be slightly under 3mm, never over.

If anyone tries the oil thing, please don't use motor oil. I tried that in the early days and it seemed to help at first, but I ended up regretting it. Some people use cooking oils, look for one with a high smoke point if you are going to try this, not that I'm recommending it.

Diamond-age PLA seems to be particularly tricky with stainless steel barrels, and we've been experimenting with potential fixes for this. We usually use filament from toybuilder labs, which works very reliably: http://toybuilderlabs.com/pla-300/

You have heatsinks on your stepper drivers, right? If you do, and they're not going into thermal shutdown, they're fine. They do tend to run hot.

Zigor

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Re: Extruder Stalling Problems
« Reply #34 on: November 21, 2013, 04:48:17 AM »
The extruder speed on repeater host under the manual controls is in mm/min.  Other than the flow rate I'm not seeing a place to input 120 mm/s.

Motor oil seems like a really bad idea.  I'm using sewing machine oil and its going great so far.  What kinds of concerns does that cause? 

The average diameter of the filament I'm using is 2.95mm, just measured again to check.

The motors get burn-your-fingers hot, so I was just checking.  The heat sinks are on.


MK

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Re: Extruder Stalling Problems
« Reply #35 on: November 22, 2013, 06:31:49 AM »
Herb - we got the filament Coco was referring to from Deezmaker, so I'm guessing it's from Toy Builder. 
She and I ran a bunch more tests today on the Diamond Age filament to no avail, sadly.  It mostly happened to us when there were long travel moves, such as multiple pins/tab heads across the table.  It didn't seem to happen as much when it was one long continuous print, such as a cup.  But switching to Toy Builder worked like a charm.

whosawhatsis

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Re: Extruder Stalling Problems
« Reply #36 on: November 22, 2013, 09:20:47 PM »
The extruder speed on repeater host under the manual controls is in mm/min.  Other than the flow rate I'm not seeing a place to input 120 mm/s.
Sorry, mm/min is what I meant.

Zigor

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Re: Extruder Stalling Problems
« Reply #37 on: November 23, 2013, 02:42:22 AM »
Okay since things seemed to be going better I decided to set up my printer as a duo like it was meant to be, so I switched the drivers back, and the extruder with that driver is stalling again.  Sooooooo I'll post a video here in a bit:

http://www.youtube.com/watch?v=KbNDofAWgFk&feature=youtu.be

Tell me what this looks like to you.

« Last Edit: November 23, 2013, 03:21:57 AM by Zigor »

whosawhatsis

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Re: Extruder Stalling Problems
« Reply #38 on: November 23, 2013, 02:54:56 AM »
For anyone who's still having problems with the extruder motor skipping, we've noticed a potential assembly issue for you to check for. The screw on which the idler arm pivots is designed to screw into one of the extruder motor gearbox's mounting screws. If this screw is over-tightened, it will stress the gearbox, causing a misalignment that will increase friction. If your gearbox is missing, try loosening this screw by half a turn or so to make sure that this is not happening.

BTW, you don't have to disassemble anything to do this. Unplug the machine so the fan turns off, and you should be able to reach the screw by sticking your hex wrench in between the fan blades.

« Last Edit: November 23, 2013, 05:45:10 PM by whosawhatsis »

whosawhatsis

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Re: Extruder Stalling Problems
« Reply #39 on: November 23, 2013, 03:28:57 AM »
Zigor, are the potentiometers set to the same position on of those drivers? Can you check the voltage between ground and the vref test point on each driver, as indicated here? http://files.panucatt.com/datasheets/sd8825_user_guide.pdf

Zigor

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Re: Extruder Stalling Problems
« Reply #40 on: November 23, 2013, 04:34:16 PM »
yep they're the same.  I'll check the voltage.

midoco

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Re: Extruder Stalling Problems
« Reply #41 on: February 04, 2014, 06:10:06 PM »
I've had stalling problems on my Duo since I built it a little over a month ago.  I slightly loosened the screws on the front of the extruder.  It helped and I was able to print with my ABS and included PLA samples.   

I few days ago I received my sapphire PLA from printBL.  I started constantly getting stalling problems with the new filament (it feels harder than the other filaments I've printed with).  I wasn't able to get a complete print, but my ABS and HIPS printed fine.   I disassembled and reassembled the primary extruder to check for binding, but it didn't help.

Yesterday I decided that tensioner lever was putting too much pressure on the filament and creating extra drag.  I took a dremel to the tube that the lever locks against and made a flat spot.  This way if it didn't work I could always rotate the tube to a non-flat spot and it will be like it was before.  It worked wonderfully with my new sapphire printbl PLA that I was previously unable to complete a print with.  I have attached a picture.  I need to do more testing, but I think I might have it fixed.

midoco

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Re: Extruder Stalling Problems
« Reply #42 on: February 08, 2014, 04:40:04 PM »
update...  It didn't fix it, but it helped.

Zigor

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Re: Extruder Stalling Problems
« Reply #43 on: February 11, 2014, 05:03:50 PM »
Honestly that problem with mine has never really gone away.  I had problems with my board (Rich fixed that, I'm certain that one of the drivers was bad, plus there was bad soldering), and I've switched to using the toybuilderlabs PLA. 

Their ABS seems horrible, if I'm wrong let me know, but I ordered a sample and when  I tried to use it it just snapped over and over again right at the extruder.  So when I went to remove it from the tubing it had broken all along the inside of the tube every 2 inches or so.  I would not personally recommend their ABS natural.

Anyways, I have found ways around the stalling but with the ToyBuilderLabs PLA I still get binding at least once per print.  So my way around it is to just print extra thick walls 1mm at least (does not work well with ABS).  That way when it does bind the print won't just fall apart. 

I've played with the speed, layer height, temp. ect. but I still get the dreaded click every now and then.  Oh and I have one of those notched levers that has different tensions, its a great idea, but even with the ToyBuilder PLA I had to drill out the hole some. 

The notches are off just a hair, for my machine at least, because it was still either way to tight or way too loose.

But,  I can sorta print now!
 

Echo

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Re: Extruder Stalling Problems
« Reply #44 on: April 09, 2014, 01:48:18 AM »
I picked mine up mid-January, and noticed mine started stalling in the exact same way as well, including the mixed failure mode.

I was using black PrototypeSupply PLA that I bought in-store when I picked the printer up.

I'll try the fix and report back.

 

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