duMONT recommends the following:

 

Broaching Procedures

The broaching procedures can be found here. “Minute Man”® Broaches are designed for fast, accurate, and convenient broaching with either arbor or hydraulic presses. A study of this Engineering Section will familiarize the operator with proper broaching procedures and troubleshooting practices. If you have a specific question or problem, contact John Warner of Asher Smith Agencies, Australian distributor.

 

Doing it the right way

 

Broaching with Keyway Sets or Individual Keyway Broaches

Bushings are required. Shims are required with all but the smallest broaches, and are provided with each individual keyway broach and broach set for cutting to standard depth.

  • Select the right bushing for the bore (sizes are plainly marked) and insert in the bore of work.
  • Insert broach (which is also plainly marked for size) for the desired width of keyway into the bushing slot and check alignment.
  • Place this assembly in the press.
  • Lubricate.
  • Push Broach through.
  • Clean broach.
  • Insert shims as required to obtain exact keyway depth.
Broaching with Internal Hole Broaches

Round, Square, Hexagon, and Special Shapes. No shims or bushings required.

  • Insert broach and check alignment. (The use of a ram adapter is advised with all round, oval, D-hole broaches, and for square and hexagon broaches 1/4″ and smaller).
  • Lubricate.
  • Push broach through.
  • Clean broach.
  • Ram Speed: Always use proper ram speed to prevent chatter marks and edge wear.
  • Pilot Holes: Properly drilled pilot holes are essential for a true and clean cut. Never use a dull or poorly sharpened drill to make pilot holes.

 

Broaching with Production Keyway Broaches

No shims or bushings required.

  • Insert broach pilot into bore of part.
  • Lubricate.
  • Push broach through.
  • Clean broach.
Broaching with One-Pass Keyway Broaches

No shims are necessary. “C” style bushings are required.

  • Insert bushing in part.
  • Insert broach and check alignment.
  • Lubricate.
  • Push broach through.
  • Clean broach.

Why use Ram adapters?

 

Ram Adapters

Ram adapters, or rear guides, provide support and guidance for the broach at the shank end, minimizing the possibility of deflection or breakage. Ram adapters are recommended for all standard round, oval, D-hole broaches, square and hexagon broaches 1/4″ and smaller, and in certain other situations where an extraordinarily high degree of accuracy is required.

If a ram adapter is used as a rear guide for the broach, the hole in the ram adapter must be in alignment with the pilot hole in the workpiece. Whenever ram adapters are used they must provide a tight, true fit to both the press ram and the broach shank.

Ram Adapter to guide broach shank:

When using special broaches, all D, Double-D, and most rectangular broaches have a tendency to deflect. To prevent this, the simple ram adapter, which can be fitted to either an arbor or hydraulic press, will guide the broach throughout the cut.

 

Broaching process V’s CNC engineering technology

 

MAINLY due to it being a quick, accurate and cost effective engineering practice, broaching has ‘survived’ technology advances like CNC multi head machines by utilising low cost equipment like an arbor or hydraulic press.

Production applications in the manufacture of gears, transmissions, precision slides and motion control, surgical implants, agricultural equipment and robotics demonstrate the broad scope of work done with special broaching tools.

One of the world’s leading suppliers of broaching tools is the duMONT company, manufacturer of Minute Man broaching tools.

Minute Man provides off the shelf standard push type keyway, square, hexagonal, round and key seating broaches and accessories, available individually in the most popular metric and imperial sizes.

A comprehensive range of keyway broaching sets is also available to meet the on demand needs of plant maintenance and production upgrades. Special broaches can usually be provided within three weeks of order.

 

If you have specific questions or problems not covered on these pages, contact your local “Minute Man”® distributor, SEI Carbide Australia.




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