Speed & Feed Rates
Recommended Cutting Speeds in Feet per Minute for Drilling and Reaming Light Metals
| Material Light Metals |
Material Condition* |
Cutting Speed, fpm | ||
| Drilling | Reaming | |||
| HSS | HSS | Carbide | ||
| All Wrought Aluminum Alloys | CD | 400 | 400 | 800 |
| ST and A | 350 | 350 | 750 | |
| All Aluminum Sand and Permanent Mold Casting Alloys |
AC | 500 | 500 | 900 |
| ST and A | 350 | 350 | 750 | |
| All Aluminum Die Casting Alloys | AC | 300 | 300 | 500 |
| ST and A | 70 | 70 | 200 | |
| Except Alloys 390.0 and 392.0 | AC | 125 | 100 | 250 |
| ST and A | 45 | 40 | 200 | |
| All Wrought Magnesium Alloys | A, CD, ST and A | 500 | 500 | 1000 |
| All Cast Magnesium Alloys | A, CD, ST and A | 450 | 450 | 1000 |
Recommended material for
| Hole Diameter | Material Left (Diameter) |
|---|---|
| .090-.170 | .005-.010 |
| .171-.280 | .008-.012 |
| .281-.880 | .010-.016 |
| .881-2.50 | .015-.030 |
Feeds for Drilling
| Feeds | Diameter |
|---|---|
| .001-.003 IPR | .1250 or less |
| .002-.006 IPR | .1250-.250 |
| .004-.010 IPR | .250-.500 |
| .007-.015 IPR | .500-1.00 |
| .010-.025 IPR | 1.00 and up |
Metric-to-Standard Conversion Formula (millimeters to inches)
mm 4 25.4 = inches
Example:
12.70 mm 4 25.4 = .500 inches
Calculating Revolutions Per Minute (RPM) from Surface Footage (SFPM) Diameter
12 x SFPM = RPM
p x diameter
Speeds and Feeds
.002 – .003 per flute per revolution
.0025 x number of flutes
= inches per revolution