I make this project a few years back like an ad on for Nikodem Bartnik DIY Dremel CNC https://www.thingiverse.com/thing:3004773 but it stayed on my PC. Now I have my MINI+ and I can try it.
There is a second version with a belt pulley.
All standard part for magnets (5 mm), set screw (2,5 mm) and pulley (8 mm shaft).
I will recommend to modify the model for tight fit on handle.
I hope it will be useful for someone :')
The author marked this model as their own original creation.