This simple rocket is designed for the Estes mini motors which are 13mm x 45mm. Uploading it was a quick test of minimal cost for this simple design.
It was designed for a 1/8" diameter launch rod. This has been printed. It arrived with a slight curl in the fins, due to tight packaging. Shaping them in my hands brought them back to straight. I will probably thicken the fins to remedy the situation. Launch planned soon.