Last Saturday, we met up and testing our platform. We let it heat up to 480 F and made sure the system could maintain temperature. We added plastic and nothing happened. Smoke started coming out of the bottom of the nozzle and it made perfect rings. As seen in the video.
We got to a point where we thought nothing was going to change and we pulled out the piston to find this.
This is a combination of burnt plastic and melted plastic at the piston. My guess is the temp was too high and once the lower stuff burned it was over. This is why we have the Plan B. We already had the parts and the design was finalized.