Hi RayCAD1962,

Are you looking for a method to add threads to 3d printing models?

Are you familiar with thread inserts using heat to press into the model?

https://www.amazon.com/Kadrick-Threaded-Assortment-Printing-Components/dp/B0CPVCTXJ7?ref_=ast_slp_dp&th=1
https://www.youtube.com/watch?v=G-UF4tv3Hvc

Wayne