These are parts for a scale model rocket of the Nike Ajax air defense missile. The specific version that I constructed used a BT-55 body tube for the booster and a BT-50 for the sustainer. The result is not exactly correct scale, but close enough for me.

There are two files for the interstage. nikeajaxinterstage.scad is the complete interstage in one piece. nikeinterstage3.scad allows you to print the interstage as two pieces. You select which one to print using the phase variable. Setting phase to 0 allows you to generate the top portion with the conical nozzle and upper tube coupler. Setting phase to 1 allows you to generate the bottom portion of the coupler with the lower tube coupler. The model in the picture was made by printing the interstage in two pieces and then gluing them together. If you don't mind removing support material, you can use nikeajaxinterstage.scan.

I have not flown this rocket and as designed it may not be stable. You are responsible for making sure that when you assemble the model you test that it is stable before you attempt to fly it.

Please follow the National Association of Rocketry Model Rocket Safety Code in all rocketry activities.