Today in the little spare time I had I managed to make some progress on the granular HDPE extruder. Here are some photos.
This an old, cheap, drill press that i’m using to hold the auger and rotate it. I’m lucky enough to have inherited a drill press twice this size so i’m now using that instead. Instead of a drill press a bearing and a small stepped down DC motor would do the job also.
As the drill press is fast, even at its slowest speed, I modified it to run off a small DC motor that I saved from a printer.
This is stepped down twice, the first time to the original motor shaft and a second time to the output drill bit holder. The small DC motor is able to pivot slightly and the spring keeps the tension. The large original AC motor freewheels while in use helping to give it some inertia to smooth out any sudden loads.
This a brass pipe coupled to a steel petrol funnel.
Above is the auger drill bit in the chuck as it would be when in use.
I cut the end of the pipe in a cross sections (think pizza cut) and then hammered them in to create a tapered end. This was then filled flat and soldered closed with high temperature solder before being filed again. I’m not sure how this will preform when extruding, only time will tell.
The very tip was filled in with more solder and then drilled with a 2mm bit. I may make this bigger in future.
A few changes will be made to the final design such as an added heatsink and stainless steel feeder pipe.
That’s all so far.