Would like to hear your experience with this dual pinch wheel extruder.
http://www.3ders.org//articles/20130822-first-dual-pinch-wheel-extruder-for-3d-printers.html
I was very intrigued, but it’s way too expensive for me to even consider.
Disappointing… When I saw the name (it’s called The Kraken) I though maybe @Sanjay_Mortimer had his multi-material system of the same name ready to go. I see little to justify the price, though.
Not to mention they seem to be offering the design files only to backers at their high prices, implying it’ll never go open source.
…why do people constantly do this? Hey look, an unreleased kickstarter/indiegogo! Who has experience with it?!
NOBODY HAS EXPERIENCE WITH IT.
I don’t get it. So you want to pinch the filament from both side. Super idea. But why two steppers? Wouldn’t a gear system with one stepper make much more sense ?
Also, $350? Really?
It’s not the worlds first dual pinch wheel extruder, I made one earlier http://airtripper.com/wp-content/uploads/2012/11/sumpod-3d-printer-extruder-system-view.jpg
I noticed the dual nozzle option reverts to single pinch wheel on each filament so the original advantage is lost there.
The worm gear wear and tear could be an issue and the design does not seem to allow retraction; since the worm gear will pull the pinch wheel away from the filament on opposite rotation.
Cooling hotends could be a problem, mounting fans would make the extruder carriage as wide as the wade extruder; another advantage lost there.
A clever design though, but it cost more than my 3D printer.
@Mark_Heywood , obviously it’s not but the OP specifically states “this” dual pinch wheel extruder. We get this kind of post every week at least where some kickstarter has just gone up, and someone wants to know how many people have had experience with it. 
@ThantiK is there an open source design similar to this concept?
@Ibrahim_Kocaalioglu , there have been in the past. They’re difficult to find on thingiverse because everyone lists them as “dual” something, and if you search for the term dual, you get a lot of dual-extruder cruft mixed in.
For example this one: http://www.thingiverse.com/thing:55803
Also worm-gears have been done before unsatisfactorily: http://www.thingiverse.com/thing:28126
There was one of them that had a chain of like 4 hobbed bolts even…
Someone just wanted to be able to announce: “Release the Kraken”. Do not use this with a Prusa Medusa or the Kraken will turn to stone.
Yes, over priced, misleading info, outrages claims on speed…
I think I will keep my money…
Yeah, first my ass. We had our Steve’s extruder design over 2 yrs ago. Every H1 we shipped has one, as do the earlier Rostock max kits
First one I saw was @Aaron_Double 's, but he removed all his stuff from thingiverse when they started being assholes, so I can’t look up the data or link to it.
Funny, I just looked through the indiegogo page, and the guy who designed it apparently likes the dual motor setup for his extruder, but has a weird and awkward-looking mod on the Prusa he’s using it on to belt-drive the second Z screw instead of using a dual motor setup on that axis.
My version had 4 pinch wheels using pinion gears from RC cars. Worked well.
@Aaron_Double , that’s insane. =D
Absolutely vicious - but how hard is it to change filaments with such a system?
@Brian_Albers Here’s more info:
This was done back in 2010 when we were using geared DC motors for the extruders. With a DC motor it had an average of 63lb of force on 3mm ABS filament. That average was derived from over 20 tests with a force meter without cleaning the gears between tests.
That’s rather interesting, though I’ve not heard of using a geared DC motors for the extruder. I’ve only ever heard of people using steppers, so I’d be very interested in reading more about a possible motor alternative.
I’d also be interested in reading more about your force tests and if you did them on other types of extruders. I know not every type of extruder could be tested - there are far too many - but something give that 63lbs of force some context would wonderful.
@Brian_Albers There’s a reason you don’t hear about it anymore. Using steppers is far superior, so nobody uses the brushed DC gearmotors anymore.