I built a new extruder barrel. This time the nozzle can be removed easily. I did a simple test of heating it up and manually pushing HDPE filament through. Worked fairly well. After I got some plastic pushed through the nozzle, I let it cool down and disassembled it. Here's what I found:
These images show the motor end and nozzle end, respectively. On the motor end, there's a small amount of pooling. I'm guessing the gap is due to the shape of the drill bit. The nozzle end has quite a bit more pooling. The gap there is caused by the shape of the acorn nut.
What I'm wondering is, does this create extra resistance for the filament? If so, is there any way to prevent it? My first thought is to fill in the gaps with JB Weld. Maybe even turn the nozzle cavity into a taper.
Friday, December 21, 2007
Posted by Steve DeGroof at 9:11 PM