LOL, I think that is what happened to this one, the farmers that used it "back in the day" were not exactly careful types. (three or four well chipped blades)I didn't exactly measure it or anything, that was my eyeball measurement of the blades tho' I do have a couple decades of carpenter experience so I know I am pretty close on the size they are now...they
could actually be twentyish . :)
Was afraid tractor wouldn't have enough umph, now I know for sure. Thanks to all for the input.