Tuesday, 11 August 2015

playing with a diamond hotend

Some time ago I got a Diamond hotend threw their kickstarter

I finally got time to play with it

My main printer is a Prusa I3 plate with a ramps running 3mm filament

The diamond hotend I ordered was a 1.75 version (as 3mm wasn't available at the time)

So I needed 3 new bowden extruders, I went for the Airtripper Bowden Extruder BSP Edition
I also went for 0.9 degree steppers, to give me a bit higher control.

I whipped up some simple mounts in open scad and assembled and attached the extruders to the printer

The ramps only has 2 extruder drivers, so I had to hack on another driver. Since my gen3 electronics days I have a Pololu module I made up for the stepped extruder back then (when extruders were dc motors and stepper extruders were new)

(bad photo of external 3rd stepper driver... ) Much better picture

I then edited marlin pins.h to added in the two additional extruders. This wasn't easy, I ended up replacing pins.h with my owe that only contains ramps + 3rd extruder definitions. All the if defs are crazy in there and they had to go.

The 'finished' machine

I tested all extruders worked, but I am having some partially blocked issues.  (more on that later)

First 3 colour test Print, just a test cube, with me sending T0, T1, and T2 commands at the printer mid print when I felt it was time for a colour change.

There are many issues with this print...   my Purple line for eg is about 50% blocked Still working on this.
But still, success!!!

Lessons learned:
I can't stress this enough. Don't go all gun ho on this. You NEED to attach all three bowden cables to the diamond head before you do any extrusion. I had to learn this the hard way. I just connected one so I could test standard printing threw the new hotend. I totally forgot that plastic doesn't care what holes it comes out of. So it nicely filled up the two other E3D cooling heatsinks with molten plastic!
I'm still struggling with geting those two heatsinks cleared...