Recommended Speeds and Feeds

Recommended Speeds and Feeds (not to exceed min. or max.)

Internal Applications

Aluminum

5/16"

3/8"

7/16"

1/2"

9/16"

5/8"

11/16"

3/4"

13/16"

7/8"

15/16"

1-1/8"

1-1/4"

1-1/2"

2500/.005

1700/.007

1400/.007

900/.008

600/.008

F.C Brass

1/4"

5/16"

3/8"

7/16"

1/2"

9/16"

5/8"

11/16"

3/4"

13/16"

7/8"

15/16"

1-1/8"

1-1/4"

1-1/2"

1-3/4"

2250/.005

1500/.007

1200/.006

800/.007

500/.008

12L14

3/16"

1/4"

5/16"

3/8"

7/16"

1/2"

9/16"

5/8"

11/16"

3/4"

13/16"

7/8"

15/16"

1-1/8"

2000/.004

1300/.006

1200/.006

700/.007

600/.009

Alloy

1/16"

1/8"

3/16"

1/4"

5/16"

3/8"

7/16"

1/2"

9/16"

5/8"

11/16"

3/4"

13/16"

2000/.004

1800/.005

1400/.005

900/.006

800/.007

Stainless Steel

1/16"	1/8"	3/16"	1/4"	5/16"	3/8"	7/16"	1/2"
2250/.004	2000/.004	1800/.004	1200/.005			1000/.005

External Applications

Aluminum

3/8"

7/16"

1/2"

9/16"

5/8"

11/16"

3/4"

13/16"

7/8"

15/16"

1-1/8"

1-1/4"

1-1/2"

1-3/8"

1600/.007

1500/.008

1200/.008

1100/.008

900/.008

F.C Brass

5/16"

3/8"

7/16"

1/2"

9/16"

5/8"

11/16"

3/4"

13/16"

7/8"

15/16"

1-1/8"

1-1/4"

1-3/8"

1600/.007

1600/.008

1300/.007

1100/.007

900/.007

12L14

1/4"

5/16"

3/8"

7/16"

1/2"

9/16"

5/8"

11/16"

3/4"

13/16"

7/8"

15/16"

1-1/8"

1-1/4"

1700/.007

1600/.008

1400/.006

900/.007

800/.007

Alloy

1/8"	3/16"	1/4"	5/16"	3/8"	7/16"	1/2"	9/16"	5/8"	11/16"	3/4"	13/16"
	1800/.005			1500/.005		900/.006				800/.007

Stainless Steel

1/16"	3/32"	1/8"	3/16"	1/4"	5/16"	3/8"	7/16"	1/2"	9/16"
	2000/.004		1900/.004	1700/.004				800/.004

This chart is available to give you a starting point reference, higher speeds and feeds are possible.
Recommended RPM can vary from 500 to 3500.
Speeds and feeds can vary relative to workpiece configuration and material from .004 to .015 i.p.r.
Feed rates under .004 i.p.r. can cause chips to lose flowing motion creating excessive end loading pressure.
In all materials, the smaller the broach diameter, the lighter the feed should be.
When retracting off or out of a part use rapid traverse.

NOTE: Skid marks on workpiece chamfer can be reduced or eliminated by slowing machine spindle and maintaining same feed rate prior to engagement of broach tool to the workpiece. After engagement, increase to recommended speed. Re-chamfering may be required to remove skid marks.

Tech Data

Broach Tool Material
Most rotary broach tools are made from M-2 H.S.S., a material that provides the required edge toughness in an operation which, by nature, does not generate much heat. Other materials available are Powdered Metal (PM4) or coated with TiN or TiCN.

Fluids/Coolants
Fluids play a minor role in rotary broaching. Any type of water or oil base fluid is acceptable The chip is a flowing type and the amount of heat generated is very minimal. When internal rotary broaching in blind holes, fluids should be applied on the broaching tool tip prior to contacting workpiece and not inside of workpiece pilot hole. Trapped fluid may be unable to escape, causing inability to broach to full depth. For external rotary broaching, fluids may be applied prior to or continuously on workpiece diameter.

Alignment Instructions
It is necessary to align end of broach tool to center line of workpiece diameter by means of adjusting screws located on sides of Holder. Alignment instructions are included with purchase of Tool Holder

Pilot Diameter Preparation For Internal Broaching
A pilot hole diameter with a lead chamfer is required. The pilot hole diameter should be at minimum, equal size to the distance across the flats or inscribed circle diameter of the form to be broached. The lead chamfer diameter must be slightly larger in diameter than the form being broached.

Note: Square and hexagon holes sometimes do not require full form. In these cases. pilot as large as possible. The less material to be broached, the less pressure will be caused while broaching.

The pilot hole depth must be drilled deeper than depth to be broached. There must be enough room at bottom of hole so chips can accumulate without excessive packing.

If no chips are allowed, after broaching they can be removed with either a boring tool or a flat bottom drill. A recess at bottom of hole will allow chips to break clean. Recess diameter should be larger than major diameter of form being broached.

Pilot Diameter Preparation For External Broaching
For external rotary broaching, the turned diameter on the workpiece should be smaller than the major diameter of the form being broached. If full form is required, turn diameter .0008” to .0015” larger than the final diameter.

For starting the external broach tool on workpiece, a lead chamfer is required. A 45o chamfer should be smaller than minor diameter and larger than major diameter. After broaching, the chamfer can be turned off.