With some thought there need not be any scrap made on purpose. I learn the most just trying to carry out the projects that come along. Usually making or modifying a tool or fixture. If I just do something to do it, it seems like it doesn't stick. But I'm old. Stuff I did when young has really stuck with me.my tap wrench is too big so I need to make handles. it only holds 1/2 it has no back gears and I never use a tap or die under power