Reference Chart
Brass Feeds & Speeds Chart
Quick-look reference data for brass milling across free-cutting, cartridge, naval, and high-strength brass grades. Best used as a shop-floor starting chart before you validate geometry, chip thickness, and grabbing risk in the calculator.
Direct answer: C360 brass can start around 600-1000 SFM with carbide in milling, but lead-free and naval brass need lower SFM, controlled rake, and operation-specific validation.
Use this chart for brass alloy ranges and grabbing-risk boundaries; copper-alloy, drilling, and turning calculators handle setup-specific numbers.
Validate Brass Milling Setup Values
Use this chart for a fast first pass. Then move to the copper-alloy calculator when cutter geometry, chip thickness, alloy family, or grab risk need a setup-specific answer.
Formula Handoff
Formula handoff: choose brass SFM, convert to RPM, set chip load, then validate feed and MRR. This page gives the alloy starting window; the calculator path should carry cutter diameter, flute count, feed mode, and machine limits.
Release checks before calculator use
- Confirm the brass family: C360 can tolerate a very different starting window than lead-free C260 or naval brass.
- Use brass-appropriate rake and chip evacuation before increasing programmed feed.
- Move turning, drilling, or thin-wall work into the dedicated process calculator before release.
Worked example and release boundary
Worked example: C360 brass roughing at 800 SFM with a 0.5 in end mill converts to about 6,100 RPM; at 0.006 in/tooth and two flutes, feed is about 73 IPM before machine power, chip evacuation, and grabbing-risk checks.
Release boundary: do not transfer this brass chart into lead-free brass, thin-wall parts, drilling breakthrough, or turning work until rake, chip control, and feed-per-rev are recalculated in the correct calculator.
Reference handoff
Brass table handoff
Use this chart for brass reference ranges, then branch when alloy, turning, or drilling geometry needs setup-specific math.
Best starting point
Quick brass milling reference values for first-pass comparison.
Branch when
Turning, drilling, and copper-alloy setup release need calculators.
Free-Cutting Brass (C360 / C385)
The king of machinability. C360 (also marketed as "Free-Cutting Brass") contains 3% lead, producing small, broken chips and allowing extreme cutting speeds. Used for fittings, valve bodies, and screw machine products.
| Operation | SFM (Carbide) | Chip Load (1/2" EM) | DOC (Roughing) |
|---|---|---|---|
| Roughing | 600 - 1000 | 0.004" - 0.008" | 1.0D - 1.5D |
| Finishing | 800 - 1200 | 0.001" - 0.003" | 0.02" - 0.05" |
| Drilling | 200 - 400 | 0.005" - 0.010"/rev | — |
Cartridge & Yellow Brass (C260 / C270)
Lead-free brass alloys required for plumbing (NSF/ANSI 61) and ammunition casings. Tougher than C360, produces longer chips, and has a greater tendency to grab. Reduce rake angle and increase feed.
| Operation | SFM (Carbide) | Chip Load (1/2" EM) | DOC (Roughing) |
|---|---|---|---|
| Roughing | 400 - 700 | 0.003" - 0.006" | 0.75D - 1.0D |
| Finishing | 600 - 900 | 0.001" - 0.002" | 0.01" - 0.03" |
Naval & High-Strength Brass (C464 / C675)
Tin-alloyed brass for saltwater applications (propellers, marine hardware). Significantly tougher than standard brass — treat closer to bronze. C675 (manganese bronze) is used in heavy-duty gears and bushings.
| Alloy | Operation | SFM (Carbide) | Chip Load (1/2" EM) |
|---|---|---|---|
| C464 Naval | Roughing | 300 - 500 | 0.003" - 0.005" |
| C464 Naval | Finishing | 450 - 700 | 0.001" - 0.002" |
| C675 Manganese Bronze | General | 200 - 400 | 0.002" - 0.004" |
The Grabbing Problem
Brass usually grabs because the geometry is wrong, not because the alloy is especially hard. This warning is mostly about milling and slotting, where a high-positive cutter can pull into the workpiece.
- Solution 1: Use 0° or negative rake geometry end mills specifically designed for brass/plastics.
- Solution 2: Use 2-flute uncoated polished end mills. The open flute space evacuates chips before they can re-cut.
- Solution 3: Maintain a positive, consistent feed rate. Never dwell or pause mid-cut. If the job is drilling or turning, switch to the dedicated calculator instead of guessing from a milling table.
Frequently Asked Questions
What SFM should I use for brass on a CNC mill?
For brass milling, this chart gives a first-pass window of 600–1000 SFM for C360 roughing with carbide and a lower range for C260 or naval brass. Use the copper-alloy calculator before release if geometry, cutter diameter, or chip load control will decide the outcome.
Why does my end mill grab when machining brass?
Standard end mills have high positive rake angles that pull the tool into soft brass. Use 0° or negative rake geometry, 2-flute uncoated tools, and maintain consistent feed — never dwell mid-cut.
Should I use coolant when machining brass?
Brass generates low heat compared to steel. Flood coolant is optional but helps chip evacuation. For C360, air blast is often sufficient. For lead-free alloys (C260), light mist or flood improves surface finish.
What coating should I use for brass end mills?
Uncoated polished carbide is usually the first choice for brass. ZrN can work well, especially in mixed non-ferrous shops. AlTiN is rarely the preferred starting point because brass usually benefits more from a sharper, lower-friction edge than from a heat-focused coating.
What is the difference between C360 and C260 brass?
C360 contains 3% lead for free-machining. C260 (cartridge brass) is lead-free, tougher, and produces longer chips. C360 allows 40–60% higher cutting speeds and much better chip evacuation.