I just bought one. It's 1/8 to 1/2 in. I drilled a 1/4in thick piece of steel with it to 3/8 diameter. I did use oil to keep it lubricated. It actually worked very well.
Wayne 1938 1-Ton Farm Truck Stovebolt Gallery Forums 1989 Silverado 1996 Mustang GT convertible When I die, I hope she doesn't sell everything for what I told her I paid for it!