This is the 4th test of this Motor a J 'Class PVC Motor based on Richard Nakka's methods. The first test was successful as this was however tests 2&3 were not they both had case failures due to the inhibitors being too thin, as well as casting the Grains in high humidity which changed the characteristics of the burn. I also need to reduce the nozzle diameter to increase the pressure thus increasing the burn rate and thrust of this motor. If you have any advice or imput please feel free to comment.