New to the site and 3d printing - need a motor shaft to lego axle adapter

Hello Everyone:

I am working on a prototype and I have a need for a motor shaft to lego axle adapter for use with a stepper motor. My overall project entails controlling a stepper motor using C# via USB connection to make very small rotations what will adjust the height of a specimen stage (constructed from Legos) for a stereo microscope.

I need adapters similar (link shown below) but for 4 mm dia motor D shaft and 5 mm dia motor D shaft

https://www.cgtrader.com/free-3d-print-models/hobb...

Purpose of the adapter is allow very small and slow rotations.

I am open to suggestions options include:

• I do not want to own the model designs, ideally they can be given away for free (similar to the link).


• I need the several of the adapter pieces 3 of each (4mm and 5 mm) printed and what would be a fair price for this?


• I have no idea what type of material should be used to print these, I think Acrylonitrile Butadiene Styrene (ABS) would do.


• 3D printer recommendation for an beginner. I don't want to purchase a printer yet but it is in my plans.

Thanks

Gary Kindel