Printing Ninjaflex with Greg's Wade Bowden

I'm working on a 330x330x300mm dual extruder Smartrapcore. I have dual Gregs Wade (Bowden version), and I'm wondering if I can print flexiable filament. The Bowden tube only comes up to the end of the extruder - and the pneumatic fitting won't let me push the tube farther. Is there a flexiable filament version, or a mod I can make to my Wade?

You could try making a fully guided filament path using bowden tubes to hold the filament at all points except where it is squeezed between the hobbed bolt and idler wheel. But my understanding is that the flex in flexible makes pushing them precisely along a bowden tube quite a challenge.

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Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions

You will also want to change your idler bearing to one with a groove. You don't want to be smashing the ninjaflex filament against a flat bearing as it will stick to it and find a way out of the fully enclosed path. And with the Flexion extruder that I have on my Smartrapcore Alu machine, you don't want much tension if any on the ninjaflex filament. You only need enough tension for the teeth on your wade's to grip the filament to pull it forward, but not too much that it indents the filament in any way. Your also going to have to make sure your filament path is exactly straight between your toothed bolt and the nozzle. If this path is not exactly in line, your filament won't flow properly and create too much pushback requiring more tension which will in turn start sticking to your idler bearing.

I print flexible with a 650-700 mm bowden and it work great, I was in fact blow away by the result when I tried the first time I was reading bowden cant print flexible but you can.

You need to drill that pneumatic connector to allow the tube to go through and cut the tube in a V shape and get that V close as possible to the extruder gear/bearing so when pushing the filament it wont twist and block the extruder.

For the head I use a e3d clone its like a V6 lite, the bowden go all the way to the nozzle mid heating block in my case, you need something similar to guide it further and to allow it to melt only at the end, a full metal one will have a pretty hard time I guess.

Then you need to reduce the speed way down, and find your max extruder speed of retract, past a certain point it wont work very well , once you find the best extruder speed you can speed up the mm/sec a little but there a limit , also dont expect a great retraction ( you have to retract the very minimum) it can leave blob all around but can be counter with fast movement, on my delta I use 250mm/sec movement it help a lot. With some tinkering my exterior wall were pretty good, same as PLA for me.

I did not test ninja flex but another brand that I got in sale. its called t-flex was on sale on digitmaker.ca, perfect for a testing since ninja flex is kinda pricey when your not sure it will work.

Here the setting I use in s3d a general mm/sec of 20 and 75% on wall and solid infill 250mm/sec movement , Got my retraction speed at 40 mm/sec ( direct drive) and the retraction from 6mm (pla) to 3 mm and use -.1 as extra on restart and .1 on vertical retract and .3 coasting

Edit : I use a flat bearing on my extruder no problem, but yeah you dont need the same tension as pla or abs that true

Edited 1 time(s). Last edit at 04/06/2017 03:11PM by GroupB.

That sounds very encouraging I've not used it so it's good to know it works on bowden too. I just know that fully guided is best for all filaments.

Do you use pressure advance? And how much?

Edited 1 time(s). Last edit at 04/06/2017 03:16PM by DjDemonD.

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Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions

I've heard of people being able to extrude 3mm flexible filaments with a bowden, but never with 1.75mm.

1.75mm Ninjaflex via Bowden does work. Check my Youtube channel for this.
A Wade is not the ideal extruder for this, but you can make it work.
Try to support the filament as good as possible starting at the hobbed bolt. A grooved bearing is nice, but not absolutely neccesary. You need to adjust idler pressure to a very low setting, otherwise the filament will expand to the sides and hang.
The drilled through pushfit is a good idea, it works nicely, but needs a steady hand and maybe some tries.
Start with very low speed and increase slowly. Keep an eye on the extruder, the highest likelyhood for failure is that the filament escapes directly after the bolt.
Good luck

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What exactly do you mean, drill out the pushfit? I was thinking of drilling out the space from the hobbled bolt to the pushfit and putting a short bit of Bowden tube In there - shaped like a V, and hot glued in. Would drilling out the push fit destroy the threads?

No advance DJ , I did not look into that yet, I post picture of my result in TPE in a post in delta one of the 2 thread talking about the flying extruder I think.

When I say drill it , I mean that.. drill the center so the bowden can pass through it like the pushfit that go on the head.. Mine Full metal one from robotdigg were also too small, the tube enter it but got block in the back, so I drill it .. there no plastic thing in in mine but small metal tooth like thing, you go slowly and drill it on the other side , the one without the tube retainer. best done on a drill press for smaller movement on " Z" so you dont over drill it into the retainer. Dont forget to blow air in it and smash it a little to get all the metal out. This way your bowden are in one piece and not 2 piece where the filament can get stuck. from the V shape to the end of the nozzle in one piece of tube.