Good bye dual extrusion. You were a finicky mistress that simply required too much of my attention.
Back to a minimalist, fast single extruder. New design thought I’m trying off of another’s attempt. Printed my calibration set, then thought I really should check out my overhangs, so I printed this. That is a set of amazing overhangs!
Scaled up 3 times, an arduino for simple processes and some ninjaflex for, well other processes, one could take this print and never worry about child-support or alimony!
This makes me so excited for my #Kraken from E3D. 
Haha.
That’s amazing, did not know you were about to tackle the Kraken!
That dual set-up on a .4 nozzle never got over 40mm/sec I tried playing with the acceleration, it was simply too much mass for my current build.
Were you running support out of the other?
I tried a variety of combinations. Dual color twin sliced, support and perimeters, etc. The perfect way to utilize IMO, would be to lift the nozzle on z retraction (seen this recently), or run one nozzle.
The latter is what I am currently toying with. Two motors one extruder, retraction high enough to allow the next filament to replace. Problem arises with getting rid of the previous filament that is in the transition zone. There would need to be a Gcode additive that signaled this transfer prior to the actual color change equal to what is left in the extruder. Dependent on material, speed, and current heat input. It’s a little tricky, but this is why I leave this a hobby. :-). It’s more fun when there is zero deadline.
Recalling on that print I was not running the second extruder at all. Doesn’t have the nozzle on it.
Do you have a model for that direct extruder?
It was on thinigiverse “dual extruder for i3”. I would post links, but I really cannot suggest using it. You must slow way down, that thing was HEAVY. There is zero z axis control. You will spend hours trying to adjust height and ensuring the hotends are perpendicular to the bed. The best would be a design I’m playing with using two direct drives and one hotend. This could be done through excessive retracts. I have haunted on it now as I’m trying to get a plasma cnc together.
Oh no I meant the one that is on there now.
@Joe_Spanier sorry, I miss understood. Let me look around. It had a number of issues I started working out in SW.
The one that’s back on my i3 is the Einstein prusa invariant for a Gregg’s Wade. This has the highest print quality and control.
The only modification I make to these is to drill the hot end mount deeper. Better control, smaller moment arm. This only applies to running an E3D.