Mill 360 free-machining brass with a solid carbide end mill at about 500 SFM: 3,820 RPM for a 1/2 inch cutter, 4 flutes, about 0.0060 inch per tooth.
What RPM and feed for 360 free-machining brass?
| Cutter | Ideal RPM | Chip load (in/tooth) | Flutes | Feed at ideal RPM (IPM) | Feed if capped at 2500 RPM |
|---|---|---|---|---|---|
| 0.125" | 15,279 | 0.0015 | 4 | 91.7 | 15.0 |
| 0.1875" | 10,186 | 0.0023 | 4 | 91.7 | 22.5 |
| 0.25" | 7,639 | 0.0030 | 4 | 91.7 | 30.0 |
| 0.375" | 5,093 | 0.0045 | 4 | 91.7 | 45.0 |
| 0.5" | 3,820 | 0.0060 | 4 | 91.7 | 60.0 |
| 0.75" | 2,546 | 0.0090 | 4 | 91.7 | 90.0 |
Tools for cutting 360 free-machining brass
How does 360 free-machining brass machine?
C360 brass is the reference material for machinability ratings. It is also grabby: a drill or a tool with positive rake will pull itself in. Use zero or slightly negative rake on lathe tools and dub the cutting lips of drills flat before drilling brass.
Why a solid carbide end mill?
Solid carbide wants roughly three times the surface speed of HSS, which small cutters rarely get on a benchtop mill capped near 2,500 RPM. Carbide still earns its price in hard or abrasive material, but only in a rigid setup: it chips on chatter where HSS would just dull.
Adjust speeds with the RPM calculator and milling feeds with the feed rate calculator. The cutting speed chart compares every material.
Frequently asked questions
What SFM for 360 free-machining brass?
A starting surface speed of 200 SFM with HSS and 500 SFM with carbide, and 150 SFM for HSS drills. These are conservative for hobby machines; raise them in steps if the chips come off clean and the tool stays cool. 360 free-machining brass rates best of any common metal (the 100% reference) for machinability.
What happens if my machine cannot reach the RPM?
Run at your top speed. Running below the ideal surface speed only makes the job slower; it does not damage the tool. For milling and drilling, keep the chip load per tooth or feed per revolution the same so the edge keeps cutting instead of rubbing, which lowers the feed in inches per minute in proportion.
Other tools in 360 free-machining brass
Other materials with a carbide end mill
- 6061-T6 aluminum
- 7075-T6 aluminum
- 932 bearing bronze
- 110 copper
- 12L14 leaded steel
- 1018 cold rolled steel
- 1045 medium carbon steel
- 4140 alloy steel (annealed)
- All