1 Topic by pcm81

  • pcm81
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Topic: has any one tried rupperized extruder gear?

While playing with tension on my SD3 extruder arm i discovered an nteresting mode of failure. I should say that my extruder gear is over a year old. Anyhow if the tension s not just right, the extruder gear will eat into the fillament, creating small chips which stay inside the acrylic of the extruder and eventually clog up the teeth of the driving gear so it slips.

So, i was thinking: has any one tried a friction drive rather than tooth drive for the extruder? Basically like adding a small wide rubber band onto the gear.

2 Reply by accusedmonk

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Re: has any one tried rupperized extruder gear?

I have been coming up with ideas for this the past week.  I was thinking more of a tank track design though.  That way you have a much larger contact for friction instead of one point so you don't have to increase force on the filament to keep it from slipping.

You could easily try out your rubber band though, just print a smaller diameter pulley for the motor.  You want to keep the angle of attack of the filament about the same.  Throw a rubber band on it and see what you get!  I'm quite curious myself.

Bowden SD3, Rumba, E3D hotend, Mk5 with RtRyder changes, Direct drive Y axis and bearings, GT2 pulleys and braided fishing line, Lawsy linear bearing conversion, M3 Z screw.

3 Reply by ronsii

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Re: has any one tried rupperized extruder gear?

In the early reprap days this was tried a lot smile has a lot of side effects... but hey if you can get it to work great!!!

4 Reply by accusedmonk

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Re: has any one tried rupperized extruder gear?

I figured it had been done before, but I just haven't seen anything blogged or posted anywhere about it.  Well I haven't specifically searched for the topic either.  I'm going to play around with it just for giggles though.

Bowden SD3, Rumba, E3D hotend, Mk5 with RtRyder changes, Direct drive Y axis and bearings, GT2 pulleys and braided fishing line, Lawsy linear bearing conversion, M3 Z screw.

5 Reply by ronsii

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Re: has any one tried rupperized extruder gear?

I don't believe it has been covered very much if at all on soliforum but on the reprap forum and a few others it is mentioned quite a bit, a quick search will yield you lots of hits so you can see some of the issues... who knows maybe with some fresh ideas on the process you'll come up with something smile

6 Reply by pirvan

  • pirvan
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Re: has any one tried rupperized extruder gear?

Lately I've been having issues with the gear chewing up little bits of filament as it pulls it through and then getting clogged to the point of slipping, so I first tried some tape, then shrink tubing, but none of it worked.

Then I used some VHB tape I had (high holding strength, double face tape on a thick rubberized base).  I cut a narrow strip and wrapped around the wheel and pushed it in the groove. 

On the first go round the filament wanted to stick to the tape, but after it went around once it lost some of the tack and now moves smoothly.  I had to release some of the pressure in the pressure bearing arm, but now it work like a charm.  Granted I've only done a few small prints (about 5hours total), but it's holding up great, and it has a very good, positive drive.

To print or, 3D print, that is the question...
SD3 printer w/too many mods,  Printrbot Simple Maker Ed.,  FormLabs Form 1+
AnyCubic Photon, Shining 3D EinScan-S & Atlas 3D scanners...
...and too much time on my hands.