Extrusion size for .35 Nozzle

How wide should the extrusion into air be for a .35 nozzle? I"ve read that it should be in the neighborhood of .6mm. I've been having some trouble with my extruder skipping, and the free extrusion is around.38. I'm wondering if there is some kind of blockage in the nozzle. I've taken off the nozzle and barrel and torched them clean, but I'm still having trouble.

Free air extrusion should be anywhere between the nozzle size and slightly larger. So for a 0.35mm nozzle it should be between 0.35 and 0.5mm or so, depending on the orifice length. How easy is it to push filament through by hand?

The die swell depend on the viscosity of the plastic and the flow rate. For natural PLA it isn't much at all. 0.6 seems too big from a 0.35 nozzle though. I only get about 0.5mm from a 0.4mm nozzle with ABS.

---

[www.hydraraptor.blogspot.com]

In this case there are 2 .35mm Makergear nozzles extruding ABS at 200C from Pronterface at 300mm/min. One is getting around .6mm and the other is getting .38mm extrusions. Is this significant at all, or is the die swell more or less random within a certain range?

0.6 seems too big and 0.38 seems too small. I would expect those figures from a 0.5mm nozzle and a 0.25mm nozzle with ABS.

Is that feed rate for 3mm or 1.75mm filament?

Edited 1 time(s). Last edit at 08/19/2012 06:04PM by nophead.

---

[www.hydraraptor.blogspot.com]