Anybody have stable result with Y-shape filament mixer(?) like ‘Prometheus dual color extruder’ ?
I’ve been tuning for some days, but have one critical issue.
When retracting current filament, sometimes melted residues blocks heat breaker(threaded rod of E3Dv6). it does not happen always, it occurs 1 out of 10 maybe.
I guess, this is why they(Prometheus) choose to use PEEK kind of tube between heater block and cooling block.
Any advice?
Does anyone have parts for such a y-Splitter? I’m interested in trying it myself. Would be happy to share some experiences once I got the machine set up.
Exact same issues I faced. Some string are stuck in barrel. But this can be solved with better tool chnage script. After small fast retract Retract it slow wo it dosnet create long string. Also instead of using such kind of printed joiner use something like flux capacitor with joiner made by ptfe
Looks great! Setting mine up soon. The retraction is what’s been getting everyone on their DIY setups. I might try to search around for some 2mm ID PEEK tube once mine is completed.
@Karan_Chaphekar Yes I am still calibrating tool change script. BTW, What do you mean by flux capacitor? With joiner?
Try this script. http://www.thingiverse.com/thing:1759063
And this is flux. Capacitor. Theh have 2 filament version also but its bit older
I was thinking “man, that’s a hokey name”…then I thought about what the flux capacitor looks like and decided to post how stupid I am. 
@Griffin_Paquette I also thinking of machining PEEK(replace heatbreaker of E3d) ,If every effort fails
The key is to let the nozzle cool down a bit before you retract. This create a sort of cold pull.
This is a great topic, I am also working toward using this and was worried about retractions. Please keep sharing your experiences with this.
Thanks
Isn’t this a similar setup to the 4-roll extruder for the Mk2 Prusa? In their case the board purges the molten filament then quickly retracts the remaining filament before it is heated.
We just have to wait for prusa to release his files for his quad system
@John-Paul_Hopman Quick retract does not help to prevent filament jam in heatbreak rod. I’ve tested 3600 ~ 10000 mm/min, but all of settings are not perfect.Small blob is remained sometimes and it blocks the heatbreak rod.
I didn’t have problem with retraction, no blobs etc. problem is the strings that remain in split barrel preventing other filament going in. also the metal part on the coupling is not helpful.
Exactly the problem we had it when we tried to develop this 3 years ago at Ultimaker. 3mm or 1.75mm? We tried 3mm, on an Ultimaker Original.
@Daid_Braam 1.75mm here. What was the solution back then? Any script samples?
The solution was looking for a different method. Combined with the large amount of purging you need to do, and that you shouldn’t mix certain materials we went for a dual nozzle solution.
If you would want to develop dual printing now, I would say go for a multi head solution. Easiest to get right.
Another aspect that makes it work for Prometheus I think, is that maybe the Peek Y has an internal diameter of 1.75, not 2 mm. This would make sure that the blob at the end does not happen and allows for better re-insertion afterwards.
@Lykle_Schepers I am trying to get that part made, but i dont think i will get that same material
@Lykle_Schepers In my opinion, 1.75mm(smaller than PTFE tube) is not a good idea. I’ve noticed end tip of the retracted filament swollen a bit during retraction. So I choose retraction distance so end tip as to stay inside PTFE tube, by doing so swollen tip would not be bigger than 2mm in diameter.
If you choose 1.75mm PEEK tube, it might have chance that filament would stuck at the entrance, while re-entry.
