There have been a few threads discussing cutting material with band saws. My machine tool supplier had an Open House and one of the machines on display was a big Hyd-Mech band saw cutting 1/4" thick discs from a piece of 9" dia. hot rolled. I grabbed a disc and measured it in eight locations about 1/2" from the rim. Not too shabby really; in the direction of blade travel it tapers about 15 thou and vertically a bit less than 10 thou. The cut took about 2 minutes, maybe a bit less, with a carbide tooth blade. Price for the machine was just over $40,000.

I tried loading some pictures but had problems; I will try later.