Flexystruder v2 jamming...

Help with printing with specific plastic filaments.
CaptainBisquick
Posts: 11
Joined: Sat Apr 30, 2016 5:13 pm

Re: Flexystruder v2 jamming...

Post by CaptainBisquick » Sat Apr 30, 2016 5:15 pm

This is also happening to me. Happened once in the past, I took it all apart and cleaned everything and the jamming stopped. Then it started again yesterday. This morning I thought I had gotten everything clean, but nope, it jammed again.

tekmaster
Posts: 12
Joined: Wed Mar 16, 2016 1:13 am

Re: Flexystruder v2 jamming...

Post by tekmaster » Sat Apr 30, 2016 5:36 pm

Bad thing is that once you put apart the head for cleaning, the warranty is broken...
This is what I was kindly told...
The head just don't work for long prints.
They should honors their work.
I'm about to design a new one based on Bondtech parts. Look very promising.
Best luck!
If anyone have built big parts with the Flexystruder I'd like to know how.
I'm not bashing here, just cold facts...

CaptainBisquick
Posts: 11
Joined: Sat Apr 30, 2016 5:13 pm

Re: Flexystruder v2 jamming...

Post by CaptainBisquick » Sat Apr 30, 2016 7:42 pm

UPDATE:
My PTFE tube is damaged and worn out. The opening above the hotend seems to have widened a bit, and opposite the hobbed bolt, the teflon has been pushed down the tube, forming a divot with a lump below it. This is just wondeful, since I can't buy more tubing anywhere locally and this is going to delay my schedule. Why wasn't an idler bearing used in this design?
:evil:

User avatar
piercet
Posts: 4027
Joined: Sun Aug 25, 2013 1:37 am
Location: Battleground, WA
Contact:

Re: Flexystruder v2 jamming...

Post by piercet » Sat Apr 30, 2016 8:27 pm

CaptainBisquick wrote:Why wasn't an idler bearing used in this design?
Because the flat idler bearing tends to squish the filament too much, causing it to mushroom out the side and bore lock, or if not tightened that much, allow the filliment to distort away from the hobbed bolt. A grooved idler bearing will work if you can find one, or the bondtech extrude core in alternate designs.

CaptainBisquick
Posts: 11
Joined: Sat Apr 30, 2016 5:13 pm

Re: Flexystruder v2 jamming...

Post by CaptainBisquick » Wed Jul 06, 2016 11:58 pm

The flexystruder finally jammed it's last jam. The filament popped out beneath the hobbed bolt and put some dents and cracks in the extruder body. I'm not going to bother wasting my time printing a new extruder body, instead I just bought a Flexion extruder and I'm making an adapter bracket. At least the flexystruder lasted pretty long. Near the end I was having to replace nozzles pretty often. I really wish someone would actually test their hardware over the long-term. I've contacted both lulzbot and ninjatek, and I don't think either of these companies are committed to developing a long-term, lasting solution, for flexible material printing.

[edit]
I take that back. I just noticed that the man behind ninjaflex is the creator of the flexion extruder, which is what I'm currently working on adapting to my lulzbot mini. This is a good sign.
[edit]

Rubbermonster
Posts: 11
Joined: Fri Mar 06, 2015 9:11 pm

Re: Flexystruder v2 jamming...

Post by Rubbermonster » Mon Oct 10, 2016 9:45 am

First off I don't know how I've missed this thread up until now. I got my first flexystruder last year the moment it was for sale. That one I screwed up by testing PLA through it quickly wearing a groove in the PTFE. I replaced the PTFE multiple times because it would constantly fail at some point. I wanted at this point to just replace the main body but Lulzbot only had V1 available for download. In a desperate possession I ordered a whole new tool head. After getting me through a few months of printing it started to print like shit, having a hard time extruding. The cause turned out to be split in print layers on the main body running along the filament path opposite the hobbed bolt. Managed to get trough the job by gluing and clapping it together, but that failed eventually too. At this point The V2 STLs became available and thus began my constant rebuilding of both tool heads I had until a few months ago when I broke down and ordered a completely new one though amazon. As always it starts off great and by now I've got all my pre-checks and precautions all in place, this one is not going to fail. Well it did and very soon. It would struggle to extrude and ooze way to much material from the threads entering the heater block. so I sent it back to Amazon for a replacement. The second from Amazon almost right out of the box could barely extrude. This one turned out to have a crack in the main body where the filament path meets the base so it went back for another replacement. This third had been doing well and I'd watch it like a hawk waiting for something to go wrong, which of course has happened. Inspiring though the filament isn't getting chewed up and jamming. I think the stepper motor on this one just might be to weak to jam up the filament. Instead it slips, it sounds and looks like when the set screw on the small gear is loose but it's actually the motor itself slipping.
I've become very intimate with tool head and it's mechanical working. I've noticed that the nozzle will quickly crust over with burnt material that you need to gently scrap off with a razor blade. Also having a set of micro drill bits is handy cause I'm convinced that the burnt material can build up inside the nozzle too. Either way a good probing to clear the nozzle after 50 or so prints helps. I always notice an improvement in the extrusion rate after doing that.
TPU has been my go to filament (and I only use NinjaTek) in the parts I make for clients. Unfortunately the Flexysrtuder as been a piece of crap in my opinion... an awesome piece of crap. I think most of it's faults lie within the design and many times the quality of construction with the main body. I really hope Lulzbot is working on V3
I see that CaptainBisquick has designed and posted on Thingiverse a mount for the Flexion extruder. I'm very tempted to go down that path.

Thedurphy
Posts: 1
Joined: Fri Oct 28, 2016 12:31 am

Re: Flexystruder v2 jamming...

Post by Thedurphy » Fri Oct 28, 2016 12:33 am

Haha. I think I just not the flexystruder because of your review on Amazon. It jammed up right after the test print. I was looking forward to the mod:(. Hope the come out with a better version soon.

Rubbermonster
Posts: 11
Joined: Fri Mar 06, 2015 9:11 pm

Re: Flexystruder v2 jamming...

Post by Rubbermonster » Sun Oct 30, 2016 3:16 pm

Thedurphy,
Thanks to CaptainBisquick's earlier post and following through in designing a bracket for a Flexion extruder http://www.thingiverse.com/thing:1743791 I'm now several 8hr long prints in, and confident that this thing is going to last. The flexystruder needs an idler bearing combined with a deeper cut hobbed bolt hands down. A huge plus for the Flexion is no more need to change out tool heads for hard filaments. However I might swap back to stock for something like PLA because of the hobbed bolt though. Beware It's a 1.75mm tool head so if you've only got one 3mm machine you'll be left with a bunch of spools you'll not know what to do with. Another plus in it's favor is (well mine is at least) it's weighing 125g less than the Flexystruder. Anyone struggling with their Flexystuders should really look into this mod. I love my Taz and my Mini and will continue to be a diehard Lulzbot (Lulzboy) fan, but the Flexystruder is a poorly manufactured, overpriced, bad design that should not have made it out of testing and into the market.

User avatar
planar_dragon999
Posts: 17
Joined: Fri Oct 14, 2016 8:41 am

Re: Flexystruder v2 jamming... Clogged 3D Print Nozzles

Post by planar_dragon999 » Thu Jul 18, 2019 10:52 am

Some of my flexy prints (TPE, etc.) were failing at layer height 10 or 11 (e.g. just above the raft....) - specifically, the print head would be scribbling away furiously in mid air miles above the raft with NO filament being extruded (and a big wad of shredded filament built up around the hobbed bolt...). SOMETIMES your 3D printer nozzle is clogged, but actually theres a whole heap of things that can lead to this sort of failure.

Troubleshooting:
I disassembled the print head and left the hot end loose but still plugged into the heater. After setting the heater to 230C (i.e. TPE extrusion temperature), I still couldn't manually push filament through the nozzle. YEP. clogged.



The fixes:

1) Clean the extruder nozzle:
1.1) Mark the alignment where the fully tightened nozzle is fully screwed into the hot end so you exactly know how far to screw it back in.
1.2) Next, unscrew the nozzle / nipple tip from the cube shaped part of the hot end (e.g. where the sensors and heater are attached)
1.3) Using pliers to hold the nozzle nipple over the flame on your gas stove, torch the offending slug of TPE into a flaming booger that will easily just drip out the wide end. (dont set shit on fire here...) and keep cooking the nozzle it until you see a few puffs of smoke come out of both ends and it turns red hot.
1.4) Let it cool enough to screw it back in. There's differing opinions on reassembly temperatures, but I screwed mine back in after letting it air cool (15m) and it was fine.
1.4.1) This would be a good time to clean off any remaining residue or carbonization - brush and scrub everything down to shiny metal if possible. make sure no dust or burrs or grit is left on the component when you are done scrubbing. make sure no brush threads are left in the nozzle bore too... (if you hold it up and look through it at a light, you should be able to clearly see the dot of light through the nozzle hole).
1.5) reassemble & carry on.
1.5.1) CAUTION!: screw the nipple nozzle in CAREFULLY - match up the etched alignment marks so you know EXACTLY how far to screw it back in once you get it cleaned out... (If you overtighten the nipple you could break the threaded part off INSIDE the hot end - this is an expensive and severely irritating mistake.)

2) Clean the Bore of the Extruder Body:
If the nozzle clean (above) didn't work, remove the nozzle again then try boring out the actual inside of the body of the hexagon hot end a little - e.g. put a perfectly sized (e.g. 3mm) drill bit down the bore of the hot end assembly (nozzle removed obviously) and buzz it around in there a little. Sometimes the bore of the hot end body can be the sticking part. When you are done make sure you you clean the bore out VERY thoroughly - left over steel flakes getting pushed down into the hole of the extrusion nozzle will land you back at step 1....

3) Is the little fan pointing at the cooling fins of the heat break working properly?
If the microblower pointed over the cooling fins of the metal hot end isnt working properly, the filament can get hot too high up in the extruder bore and will stick to the walls. If you put 5v across the microblower wire pins and it doesn't blow and you can't get it blowing properly with some gentle tinkering, try replacing this component. Of interest, you can remove the casing (look for the clips around the sides and gently pry them loose). Sometimes crap can get stuck between the blower impellor and the electronics beneath it that fire the stator coils of the DC motor drive. In my case, I had a wad of hair and melted plastic stuck in there...

4) Dial the extrusion temperature down:
Same thing - if heat is getting too far up the heatbreak the filament melts early and sticks. Try incrementing your extrusion temperature down.

5) "Reduce your "Retraction" setting:
If you retract molten filament too far up into the extruder bore and it gets into the heat break, this can cause clogs too. Try incrementing your retraction settings down.

6) Make sure the drive gears can spin freely!:
One time I discovered a print failed because the bolt locking the drive gear onto the shaft of the stepper motor had come loose - it had unwound itself far enough to catch on the frame of the extruder body (instead of clearing the inner diameter cleanly and letting the motor do its thing...)

7) Is your filament clean going into the extruder?:
Dirty filament can pull dog hair, scales, dust and grit into your printer's toolhead bore. Clean the filament surfaces off carefully. I superglued a foam block on my toolheads filament intake and I was amazed at the amount of crap i have to clean off after an extended print, even with my filament stored (relatively ) carefully.

8) make sure your filament isnt getting stuck coming off the roll:
sometimes the filament can knot up or get caught in something on its way into the extruder - i.e. it's stuck before it even gets to the tool head... check the whole filament unspooling path.

9) Is stuff getting pushed (or sucked) back into the nozzle??:
If your nozzle tip is too low (and/or your retraction is too high) you can push or suck debris up off of your printing surfaces into your nozzle that shouldn't bee there. Make sure your bed surface is nice and clean for each print and that your nozzle is leveled properly. Make sure your retraction settings are dialed in properly for what you are trying to print...

10) 2 other quick words for the wise:
10.1) store your 'struders carefully! I leave a bit of filament sticking out of mine to prevent debris from falling into the extrusion cavity...
10.2) Have a few spares around. This includes Nozzles, hot ends, heat breaks, sensors, drive gears, fans, bolts, molex pins & terminals, etc.

Most of the above suggestions are a result of a rather painful {experiment, (fail/repeat), succeed} process, but some credit is due to the other brave bloggers out there who noted a few that helped me as well.

Cheers to all & happy printing!
Last edited by planar_dragon999 on Wed Aug 21, 2019 9:12 pm, edited 9 times in total.

User avatar
planar_dragon999
Posts: 17
Joined: Fri Oct 14, 2016 8:41 am

Re: Flexystruder v2 jamming...

Post by planar_dragon999 » Thu Jul 18, 2019 10:57 am

piercet wrote:
Sat Apr 30, 2016 8:27 pm
CaptainBisquick wrote:Why wasn't an idler bearing used in this design?
Because the flat idler bearing tends to squish the filament too much, causing it to mushroom out the side and bore lock, or if not tightened that much, allow the filliment to distort away from the hobbed bolt. A grooved idler bearing will work if you can find one, or the bondtech extrude core in alternate designs.
huh... any way to print a grooved idler bearing?

Post Reply