Hi Velleman Support Team…
Guys will you be updating the K8200 with a dual extrusion, or with a SD Card slot and Display?
Whats coming? And when ? 
Jens
Nice…
If you need testers … Let me know
Jens
let me know to
let me know too
So is there an upgrade for duel extruders???
The good thing about an open source kit like the 8200 is that you don’t have to wait for an “official” solution from Velleman. In fact, they already sell almost everything you need to do this.
I am building a K8200 with dual extruders. I have a pair of K8203 extruders that will be assembled in mirror image. Then I will replace the controller board with an Arduino Mega and a RAMPS 1.4 shield, which will give me the second extruder output.
Marlin and Slic3r support this, so the hard work has already been done. I am just stumbling along in the footsteps of others…
Construction of a dual extruder K8200 is going well. The pair of K8203s went together easily, and it was very nice that redundant parts were included to allow building the extruder in either left- or right-hand orientation. It seems like a solid mechanism. I did have to adjust them after they were installed to get the nozzles the same height above the bed.
It didn’t take a lot of time to modify the firmware to enable dual extruder support, although it was not as clearly documented as I had hoped. It required only changes to Configuration.h and Pins.h.
Everything on the printer was working for the first few minutes. But then just before I could make my first test print, the controller lost its ability to turn on two of the heaters. So I am now diagnosing a likely failure in the RAMPS controller board.
I’ll do a complete write-up once I have it actually printing, but at this point I have no reason to believe it won’t work.
It must be a firmware problem. I tried a second RAMPS board and another Arduino and had the same behavior. I also wrote a simple test app that toggles D8, D9, and D10 once per second and found that all three heaters and their thermistors are working. So I think that rules out a hardware problem.
Does anybody have any experience configuring a RAMPS controller for dual extruders? I think I am just missing a step.