How difficult is to replicated that feeder. It seems passive .
https://www.kickstarter.com/projects/811909269/the-prometheus-system-intuitive-multi-filament-3d?ref=ksrfb
There was a RepRap that did the exact same thing years ago. Would have to go hunting to find it though.
Not very difficult. I will give this one a try
I think I saw an even older one once.
Yep. I think we could just print that block. The interesting part is sourcing that smaller ID tube to go into the E3D, I think theirs is made from PEEK.
And the gcode generation / Tuning is the really interesting part
@raykholo Not clear to me why you’d want a PEEK part for that. Should be PTFE if you’re using it as a meniscus barrier. (Stratasys actually has a number of patents on the subject, if anyone feels like going down a rabbit hole.)
Well, we’d need a 4mm OD and sub 2mm, probably 1.75mm ID, tube, to replicate what the Prometheus guys advertise. I’d be ok with PTFE too but I’m pretty sure they said PEEK.
TriDPrinting.com sells a 1.8x4 PTFE tube: http://www.tridprinting.com/Hot-Ends/#3D-Printer-PFTE-Teflon-Tube
Yep, that’s what we’d need. I haven’t found it on ali or ebay.
PTFE lined hotends may not even need the PEEK shaft.
Worth investigating on my E3D Lite
@Jason_McMullan the point I was trying to make is that while most hotends have a 2mm ID PTFE tube, the Prometheus uses a smaller ID tube to reform the molten filament as it is yanked out and prevent a plug from forming.
@raykholo I suspect you could get good results by swaging down the ID of the PTFE tube slightly smaller right across the heat break. Maybe tighten a compression fitting on the PTFE liner, then remove and assemble into the hot end.
I think they called it “bearing grade PEEK”. That might just be a meaningless marketing term or there might be a variation that has additives for lubricity and non-stick properties. To me the most worrying part was attaching a torquey geared motor to an acrylic extruder. That just strikes me as a bad idea.
Eric claims that PTFE wears too much, and that it has to be PEEK.
Graphite loaded vespel.
Both graphite PEEK and graphite Vespel would make sense.
@raykholo what would need to be done so smoothie hankies this change?
I don’t think you need any special firmware at all, just some suitable toolchange gcode in the slicer. Your standard dualstrusion setup will work fine as long as it can handle a 0,0,0 tool offset and allows you to extrude on the second tool without having a second thermistor reading hot.