And also a new extruder drive to go along with it. Looks like it grabs the filament at both sides to improve grip!
Originally shared by Brook Drumm
https://www.youtube.com/watch?v=Ox47ESk8DE4&feature=autoshare
I am going to be SO broke!
I thought about that dual gears design for a long while, but ultimately dismissed it because of the missing release. I tried some designs with a tensioner and release system, but the ones i was capable to design weren’t good enough. The ptfe tube idea has been tried by many. For me it fell short when it came to speed. It does work with very flexible mazerials, but only with mediocre speed. What does work is having a continous ptfe tube with openings for idler and transport. With that design i am able to print ninjaflex at the same speed as abs or pla.
I like the design proposed here, but would love to see it taken one step further.
My concern about the design of this is that if filament does get stuck or the gears strip filament and need to be cleaned it is not as easy to get to the gearing. Looks like you have to unscrew the whole extruder to get to the insides. I know, I know many companies have extruders that are hard to get into but there is something about the alu extruder that makes my printer easier to troubleshoot. I won’t know for sure until I get my hands on one but from initial viewing that’s my thoughts.
Any plans on marketing this in an alu version along with the injection molded? I love the look and a black plastic piece would look out of place in my simple. 
Injection molded version of the aluminum extruder would have been perfect. I might give the ubis all metal hotend a try, but not sure about this extruder since I’ve already converted to Bowden drive.
I think a quick release can be done. I don’t know if this is worthwhile in the long run. If the nozzle jams, you’re stripping filament anyways. The chances the extra force can push the jamming debris through seems low.
Yeah one of my issues with the Rep2 is that any clogs or stripped/snapped filament required me to disassemble the extruder. This one looks much easier to dismantle though.
I did not mean for cleaning, but for fast filament change. Especially with a bowden it is a nuicance
As far as the injection molded part. I’m sure this material is best but is just can’t get over the look of a nice piece of alu on the front of my bot. I’ll def be trying this set up out as soon as the part kit is on sale.
How will this cope with filament of varying diameters? Extruders without springs have been tried before… they were replaced with spring loaded extruders for a reason…
On my old machine i use a Wade derivate that does not employ a spring but a slightly elastic double sided rubber tape. We are talking about a few tenths of flexibility. That is already enough for most 1.75 filaments. I also tried without any elastic component as well and it did work too, but the risk of damaging the filament when changing it was to high for me.