Feeds and Speeds
EPIC “Rule-of-Thumb” Speeds and Feeds
These prototyping speeds and feeds keep our tools sharper and your parts safer. These speeds and feeds apply to our CNC machines.
High-Density Polyethylene (HDPE)
Our favorite engineering plastic – easy, quick, and clean to machine. HDPE Wiki
| Tool | Speed (RPM) | Entry Feed (IPM) | Contour Feed (IPM) | Z Step (in) |
| 1/8″ End Mill | 5000 | 18 | 20 | .0625 |
| 1/4″ End Mill | 4500 | 22 | 25 | .125 |
| 3/8″ End Mill | 4000 | 22 | 25 | .1875 |
| 1/2″ End Mill | 3500 | 22 | 25 | .25 |
| 1/4″ 90° Spot Drill | 3000 | 10 | — | — |
Acrylic
| Tool | Speed (RPM) | Entry Feed (IPM) | Contour Feed (IPM) | Z Step (in) |
| 1/8″ End Mill | 4465 | 15 | 17 | .0625 |
| 1/4″ End Mill | 4250 | 19 | 21 | .125 |
| 3/8″ End Mill | 4040 | 19 | 21 | .1875 |
| 1/2″ End Mill | 3825 | 19 | 21 | .25 |
| 1/4″ 90° Spot Drill | 2600 | 8 | — | — |
Polycarbonate
| Tool | Speed (RPM) | Entry Feed (IPM) | Contour Feed (IPM) | Z Step (in) |
| 1/8″ End Mill | 5250 | 18 | 20 | .0625 |
| 1/4″ End Mill | 5000 | 22 | 25 | .125 |
| 3/8″ End Mill | 4750 | 22 | 25 | .1875 |
| 1/2″ End Mill | 4500 | 22 | 25 | .25 |
| 1/4″ 90° Spot Drill | 3000 | 10 | — | — |
Aluminum
| Tool | Speed (RPM) | Entry Feed (IPM) | Contour Feed (IPM) | Z Step (in) |
| 1/8″ End Mill | 5000 | 16 | 18 | .04 |
| 1/4″ End Mill | 4500 | 18 | 20 | .1 |
| 3/8″ End Mill | 4000 | 18 | 20 | .125 |
| 1/2″ End Mill | 3500 | 18 | 20 | .1875 |
| 1/4″ 90° Spot Drill | 3000 | 10 | — | — |
Carbon Steel (Wrought)
| Tool | Speed (RPM) | Entry Feed (IPM) | Contour Feed (IPM) | Z Step (in) |
| 1/8″ End Mill | 3973 | 7.95 | 7.95 | .04 |
| 1/4″ End Mill | 1986 | 5.96 | 5.96 | .083 |
| 3/8″ End Mill | 1324 | 3.97 | 3.97 | .125 |
| 1/2″ End Mill | 993 | 2.98 | 2.98 | .167 |
| 1/4″ 90° Spot Drill | 3000 | 1.07 | — | — |
Calculating Your Own Speeds and Feeds
Cutter selection and material type matters – ask a staff member for help!