The final stage of my scrap plastic-to-pellet project involves ensuring that the material flows properly through the feed hopper.
I awoke in the middle of the night and realized that this is the same issue encountered with the extrusion machine. The difference is that I am now feeding the material down a 6-inch (150 mm) circular opening rather than a 2 × 3-inch (50 × 75 mm) rectangular opening.
It is the same problem, only with a differently oriented hopper.
I have therefore devised a rather unconventional solution. I will construct a bracket above the machine and suspend a probe-like device into the feed hopper, positioning it so that it terminates just above the feed rollers. The probe will be mounted on rubber to permit limited movement, and a vibrator motor will be attached to it.
When powders and flakes are subjected to vibration at appropriate frequencies, they behave like fluids. This is analogous to the principle underlying oobleck, a shear-thickening fluid.
It is Saturday morning here. I am calling an employee in to work so that I need not wait until Monday to test the arrangement.
update
Installed a mounting bracket and suspended a angle bar with the vibrator into the feed hopper. It was more reliable but still can be much better. Revising the design to try after lunch. Basically a 18 inch length of round bar suspended on a chain and the vibrator attached to that.
update. that idea worked not so mucho.
Ordered the rubber isolation mounts i use on the other machine. Put everything away, called it a weekend.