From DT Online
Broaches provide a means of re-shaping a previously drilled hole by pressing or striking through it a tapered cutter.
Features and Uses
Broaching is generally a machining process in which shaped cutters are pushed or drawn through pre-drilled holes to modify their shape in some way (e.g. to make them square or to cut grooves or Keyways inside a hole if used with a guide piece as shown).
- If a suitable section of Tool Steel is not available, Broaches for the small-scale work most common in Design and Technology (in Brass for example), can be made by grinding teeth profiles into the shortened length of an old file for example (ideally, first Anneal the old file and re-shape it then re-harden and temper to ensure the finished Broach is not too Brittle).
Safety Point! If making from an old file, use a short length, grind a chamfer around the striking end, apply only light taps to reduce the risk of pieces breaking off, and always wear eye protection.
|2pcs Tool Steel 6mm x 200mm Round Rod||100mm x 5mm HSS Ground Shaft Round Rod 5Pcs||8mm x 200mm Steel Round Rod||10 Pcs High Speed Steel Round Bar 4mm x 100mm|