I haven't had a chance to do much work on the TR-1 motor...I'm satisfied with the design and am ready to start machining. I just need to finish machining the hardware that I mentioned in my previous post.
I modeled the nozzle in 3D. I find that this helps with the machining if I can move the part around and think how best to machine it.
MiniSShot nozzles that I machined in that it consists of two main pieces. There were a number of reasons that we chose to construct the MiniSShot nozzle in two sections, but for the TR-1 motor the decision was made simply to ease fabrication. Constructing the nozzle from two pieces allows me to use some stock that I had on hand and more importantly significantly reduces the amount of material that I'll need to remove. I have a piece of 1018 for the shoulder portion of the nozzle and some 12L14 for the convergent/divergent piece.