Underextrusion / Extruder jamming ... slic3r question
This is my first post here, I hope I am at the right place since the question is about slic3r and repetier too.
I can't get a good print when I try to print under 0.3mm on a Afinibot Prusa I3.
I can hear the "clunk clunk" sound from the extruder, so I am guessing there too much backpressure in the nozzle. ( The drive voltage/current has been tested and the extruder springload has been tested too )but I can see the motor not having enough tork when the nozzle isn't free.
So, my question about is what speed should I use to free the nozzle end to have a good print ?? Or should I raize the Z a little bit ?
Maybe I am printing too slow or too fast, I'm not sure about that.
Question about repetier : How can I increase the z axis while printing ?? I want to try something to get rid of that problem.
Bonus question : Glass makes a better finish but is harder to get a good first layer, should I go back to blue tape ?
Thanks guys !
Had to stop the print because it would have been too weak. ( this is a wall hook )
p.s. i'm using Repetier Host 1.6.1 with Slic3r 1.2.9