Welcome to the SeeMeCNC Community

Okay, after a few days of wondering why I can't print ninjaflex with the simple extruder mod mentioned on this forum I decided to just make my own part and after a few revisions it worked out amazing


i couldn't print at 10mms even for a minute without a major jam no matter what I tried.. I had the PTFE tubing right up against the gears with a cut allowing no extra space, glued it in place but still major jams.


So with this new setup I've eliminated all of my issues with

- retractiion slipping the filament behind the idler bearing
- filament buckles and jams under the hobbed gear
- filament expansion jams
- filament drag near extruder


This is working out great and I figured i'de share.

I am limited to about 30mms - maybe I need a stiffer spring but I thnik its very tight as is... the gear will slip on the filament if its going to fast however it doesn't really ruin the print since the filament keeps sprung tension the whole time.

I am using 10mm fast retraction right now as a test and for the last hour it hasn't hung up.

[img]http://upload.streetlegalmods.com/images/2014/09/24/10678739101522907005762461228355454726161951n.th.jpg[/img]
[img]http://upload.streetlegalmods.com/images/2014/09/24/10678628101522907008462465471015235514927737n.th.jpg[/img]
[img]http://upload.streetlegalmods.com/images/2014/09/24/10665684101522907010312468226764928268369028n.th.jpg[/img]
[img]http://upload.streetlegalmods.com/images/2014/09/24/1064661210152290700541246793215842516177543n.th.jpg[/img]
[img]http://upload.streetlegalmods.com/images/2014/09/24/10645258101522907006462467957788031796673654n.th.jpg[/img]
[img]http://upload.streetlegalmods.com/images/2014/09/24/10418983101522907007512468833699686832132398n.th.jpg[/img]
[img]http://upload.streetlegalmods.com/images/2014/09/24/10419059101522880557012468784515523546562860n.th.jpg[/img]
[img]http://upload.streetlegalmods.com/images/2014/09/24/10418435101522907006812467660663951537766662n.th.jpg[/img]

How did you tackle all those issues? I need to know what you did differently!

you can see it from the design difference here
[img]http://upload.streetlegalmods.com/image ... 90344n.jpg[/img]

the filament has support above the gear and idler so it cannot get out alignment and slip behind the idler and lose its "pinch" or grab on the filament.

this also helps keep retraction under control i have it set to 10mm retraction at 50mms for testing and it hasn't jammed up yet.


i brought the filament support as close to the gears as possible and it still wasnt enuogh the first time around so in this latest revision you can't even see the filament when looking at it from the idler side... but it has solved the buckling completely.

also chased the holes with a drill bit and dremeled the curves along the hobbed gear to be an exact fit it almost looks like its rubbing but its not.


also note that the picture with the red ninjaflex filament is just a short scrap piece i put in to test the drag and movement, thats why it looks curved.

Did you have to tap the threads for the bowden fitting, or did you make the tolerance just right for "self tapping"?



Also, is it up on Repables yet? I want one!

hey,


i used a drill bit at the end of the hole to increase the size enough to self tap the fitting. its been holding up really well so far i've printed a lot with it.

I'm going to keep printing and see if there is anything to change before i release the file. I think i'll make it print with the right size hole for the fitting from the get go so you can just self tap the fitting in and go.

I'd definitely be interested in this too. It looks great

Hey guys, here it is

http://www.thingiverse.com/thing:488678

Its a work in progress but i've been using it without issues so far !

You do have to drill a little depth in the bottom for the filament tubing coupler but thats all. everything else should be plug and play....

singh336 wrote:Hey guys, here it is

http://www.thingiverse.com/thing:488678

Its a work in progress but i've been using it without issues so far !

You do have to drill a little depth in the bottom for the filament tubing coupler but thats all. everything else should be plug and play....

Thanx a lot for this.
Which program you designed it in? Are you willing to post your file? Would like to change it for my extruders combi for dual extrusion. And for that .stl wouldnt help.

Thanx
Dirk

3ds max, and you should be able to import STL no ?

I can always import stl models into max and modify them as needed.. let me know

I'll be making this modification to my printer here soon. I'll let you know how it goes for me!

singh336 wrote:3ds max, and you should be able to import STL no ?

I can always import stl models into max and modify them as needed.. let me know

Nice design. I'm also interested in the design file (or rather a solid). Could you provide f.ex. a STEP file of the design?

Thanks!

This ended up not working very well for me...

I could have made it work with a little mroe effort but I just ended up going with Guanu's method.

Nice part design though! Keep up the good work!

A bit of necro, but is this custom extruder for the people who got older kit extruder? I can't seems to figure out the difference between this and the EZstruder from the stores.
I am willing to buy flexible filaments, but prefer to get all the set up ready before realizing I got screwed.

I don't have any flexible filaments, but I printed one anyway to see how the design is. I do like it quite a bit. Its a bit more difficult to feed the filament into the guide at the top, but once you find the hole it glides right through into the bowden tube. Excellent design, didn't even have to use a dremel.

I kinda wish it mounted like the regular Ez, I think my retracts will be loud (Birch seems to amplify the motors a bit more). Also you should check the file on thingiverse, the top part of the filament guide interferes with the idler lever in the file, but on yours it shows it gets cut off right at the top of the hole (see your sixth picture posted, the upper filament guide before it reaches the idler and drive gear) I trimmed it with a razor blade and it works fine.