This is my take on the a minimalist/nano pod motor mount for a 6384 motor for the inside 4mm bolt pattern of 30mmx30mm. I only have an insert for an Axis 19mm aluminum mast and a generic AliExpress hydrofoil mast. I included a blank insert that could be used to make your own insert for whatever mast you have.
The TPU insert and strap is best printed from 85A and the mount itself should be printed from ASA.
Hope this is useful for someone.
