Extruder Tension Help for Printing Flexible Filament
I have the MK3 Assembled Unit and have printed about 4 parts so far with everything as is with the stock gray PLA. Everything came out great.
Now I'm trying to print some 3D Solutech Flexible Filament, prints at 200-220C and is TPE and the filament is very flexible.
I'm printing a gasket for the Spannerhands V4 spool enclosure. Everything prints OK until about the 5-8 layer. I'm not watching the entire time so I'm guessing. It seems to do alright for about 30 minutes then the filament starts coming out the side of the extruder.
I've been using the stock setting in Slic3r Prusa Edition for Flexible filament and only changing the temp to 215C.
It failed the same way both times, but the second time I loosened the extruder tension screws as suggested by Prusa Material Guide. That didn't help. Unless I don't have it loose enough.
Just to mention when I went to loosen the extruder tension screws they already seemed very loose. I can't find anywhere instructions for the MK3 on how to accurately adjust those, nor can I find a guide to figure that out.
Any help would be appreciated.
Re: Extruder Tension Help for Printing Flexible Filament
Hi Carter,
with no filament in the printer, I screw the tension screws in, until they just touch the springs and leave it at that
when the filament is inserted, it parts the Bondtech gears and increases the tension just right...
the ends of the screws are just about level with the outer surface of the filament trap door, on the right hand side
regards Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
Re: Extruder Tension Help for Printing Flexible Filament
Thanks. I read that when you posted that in another thread. I did that and the flexible filament spilled out still. Any other suggestions? I even cut the speed and set it all to 30mm/s.
Re: Extruder Tension Help for Printing Flexible Filament
I even cut the speed and set it all to 30mm/s.
Way too fast for a very flexible filament. Richard will probably be along soon to tell you to use 15mm/s 😉
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…
Re: Extruder Tension Help for Printing Flexible Filament
I even cut the speed and set it all to 30mm/s.
Peter is correct, that is way too fast. Max should be 20mm/s but I get the best results at 15mm/s.
Re: Extruder Tension Help for Printing Flexible Filament
Listen to Richard, look at what Ninjatek advises for Ninjaflex :
Extruder Temperature: 225°C – 235°C
Platform Temperature: Room temperature – 40°C
Glue and/ or blue painters tape is suggested if not using a heated bed.
Print Speed:
Top and bottom layers: 10-20 mm/ sec (600-1200 mm/ min)
Infill speeds: 15-35 mm/ sec (900-2100 mm/ min)
Layer 2+ use cooling fan if available.
Source: https://ninjatek.com/products/filaments/ninjaflex/
Minus the temp difference, the speeds should be around this range( I run infill at 20mm/s, everything else 15 for flexibles)
Anything can be made better
https://www.myminifactory.com/users/Joe%20Prints
Re: Extruder Tension Help for Printing Flexible Filament
Great. I'll try that.
Re: Extruder Tension Help for Printing Flexible Filament
I'm using the stock flex filament setting in the Slic3r Prusa Edition, the only thing I changed is the temp and the speed. The stock extrusion multiplies is set at 1.2. Should I leave it like that or change it?
Re: Extruder Tension Help for Printing Flexible Filament
OK SUCCESS!!! Thanks everyone.
So I had to slow it down to 15mm/s for everything except travel speeds. As Joan said screw in the extruder screws until you feel tension. This is tough as you can barely feel when it hits the springs. You have to do it with the allen wrench loosely held in your fingers. And i had to change the extrusion multiplier to 1.
Re: Extruder Tension Help for Printing Flexible Filament
Awesome! I did forget to mention that you will want the fastest travel speed you are happy with ( I use 170mm/s)
Anything can be made better
https://www.myminifactory.com/users/Joe%20Prints
Re: Extruder Tension Help for Printing Flexible Filament
I'm using Matterhackers Flex Pro TPE and having mixed results.
My first print worked great with the standard Slic3r settings (handlebar grip for my kid's BMX) , but the second, identical, print failed multiple times. It seems that the extruder drive gears force a kink in the filament, which then wraps around either the driven or floating gear, jamming the extruder.
I tried loosening the screws, that worked for one print so I declared the problem fixed. Then the next print failed and several after that too. I turned up the heat, had a good print, followed by a couple of fails. I slowed it down to 10mm/s - and it passed. Then, on the next print, it failed.
I'd starting to think that it does not matter what I do - it's just some random thing, which is frustrating.
Has anyone tried adding a rigid tube closer to the extruder gears? I don't want to disassemble my extruder and go through the whole setup effort again, but it's looking like the best approach at this point.
Has anyone come up with a really reliable flex filament approach?
Re: Extruder Tension Help for Printing Flexible Filament
Also, I'm wondering whether time of day matters. I did not take notes, but I speculate that my morning printing efforts worked, but the afternoon did not - making ambient temperature a suspect. Maybe I'll try tossing the filament in the fridge before printing and see if that helps.