duMONT Minute Man® stock Broaches can be used on a variety of workpiece materials, it is not practical to Broach material having a Rockwell hardness higher than Rc35. When broaching Iron or Steel use the standard Broach as supplied. Brass and Free Machining Bronze may require stoning of a slight land on the top of the teeth to prevent drifting (pulling into the work). Special Broaches are designed and engineered to provide the correct tooth form, pitch and rake angles for the material specified. Please contact duMONT for more information on hard to Broach materials.