This weekend we pulled out the static test stand and continued with more testing. Before the tests we spent a couple of hours making the flexible nozzle membranes and the tools to make them.
Dad machined up the stamp tool that cuts the membrane out of the rubber sheet to the exact size (the brass component), and then the hole punch alignment tool, that allowed us to center the hole punch in exactly the middle.
We ran about 14 tests with different materials and different sized holes. We haven't had a proper look at the data yet, as that will again take a couple of weeks to analyze and write up. One interesting surprise we did get was during one particular test the nozzle made a pretty loud whistling noise. We might fly that one on the next launch day just for fun.
We'll post the full data on the nozzles when the analysis is complete.