Finally got my capacitor in today but I have some stuff to rethink first. Firstly, that the store bought nozzle was a bad idea and no matter how much I work on it, it will stay so. Why you may ask? The most important part of a rocket's injection system is the flow rate. The suppliers of these nozzles do not have the same concern. They are more concerned with the spray patterns and distribution at given pressure differentials. My pressure differentials are arbitrary. Hand-wavy estimates between 10-30% of the combustion chamber pressure is the differential I need to overcome to prevent chugging and other oscillations. What -is- important is that my holes restrict the flow to a certain amount of flow no matter what the pressure differential is... That's why using a spray nozzle is a bad idea.
So resetting with what I have learned thus far, I noticed that in testing the oxidizer flow I had to wait for the entire injection system to chill down to -40F before liquid made it out of the nozzles. I feel a large part of the lag time comes from the bulk thermal mass that the nitrous has to interact with on its way into the chamber. So I will be moving the oxidizer to the inside of the injection pattern. I will also be thinning out the injector plate so that there is less too cool and it will also help me heat up the fuel a little bit quicker.
Apart from redesigning my entire injection system, the thrust stand is underway! I milled the main 1/8" steel plate to fit flush with the structure of the stand before starting to mount the top and bottom plates, also 10G steel with 10 1/4" steel bolts. Once I get my 1/4" lexan later today, I will cut and stack triple layers (3/4" total) on either side of the stand to complete the enclosure. In theory, it can take a 9mm bullet from any direction... hopefully we don't need to test that part out.
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