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Speeds and feeds

932 bearing bronze speeds and feeds with a HSS end mill

90 SFM starting surface speed. Hardness 65 HB. Machinability: Good.

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Checked2026-09-24
Quick answer

Mill 932 bearing bronze with a HSS end mill at about 90 SFM: 688 RPM for a 1/2 inch cutter, 4 flutes, about 0.0030 inch per tooth.

What RPM and feed for 932 bearing bronze?

CutterIdeal RPMChip load (in/tooth)FlutesFeed at ideal RPM (IPM)Feed if capped at 2500 RPM
0.125"2,7500.000848.37.5
0.1875"1,8330.001148.38.3
0.25"1,3750.001548.38.3
0.375"9170.002348.38.3
0.5"6880.003048.38.3
0.75"4580.004548.38.3

Tools for cutting 932 bearing bronze

How does 932 bearing bronze machine?

SAE 660 (C932) bearing bronze is the usual stock for bushings. It machines cleanly into small broken chips. Like brass it can grab a drill, so a flatted drill lip helps, and it runs happily dry.

Why a HSS end mill?

HSS end mills are the forgiving choice on a light hobby mill: they tolerate chatter and interrupted cuts that chip carbide, they are cheap to replace, and they cut well at the modest spindle speeds benchtop mills offer.

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 932 bearing bronze?

A starting surface speed of 90 SFM with HSS and 300 SFM with carbide, and 80 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. 932 bearing bronze rates good 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 932 bearing bronze

Other materials with a HSS end mill

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