Join me in the machine shop where we’ll make a tap wrench. I want it to be really nice, so rather than reinvent the wheel, I’ll be mimicking a Starrett 91C. We will be using the engine lathe and the vertical milling machine for most of this DIY tool project and making use of materials I already have. Which is mostly mystery steel. But the body material just so happened to be marked as O1 tool steel. The design isn’t exactly manufacturing friendly and will require some creative ways to make many of the features. We’ll be getting into knurling, taper turning between centers, hand filing square holes, and radius turning without a radius turner, just to name a few. With so many operations, let’s just hope I get through this without any machining fails **cough cough**