On Sunday, April 10, 2016 at 5:09:20 PM UTC-4, Ignoramus6088 wrote:
Hello, I need to make a ball screw and ball nut to 0.0001" accuracy
without any tools. Please help me with creative ideas.

i

I suggest you get the foxfire books. They have a lot of backwoods articles and I am pretty sure one has an article on making marbles by putting stones in a fast running stream and with time they become spherical.

https://en.wikipedia.org/wiki/Foxfire_%28magazine%29

Dan