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How to Use an Arbor Press
Guide · Updated October 28, 2026
A manual arbor press uses a lever and rack-and-pinion to push a ram. It is ideal for small bushings, dowel pins, bearings and keyway broaching, with good feel for how hard the part is going.
Check the fit first
Measure pin and hole before pressing. The free Gage Block Calculator builds the stack.
Step by step
- Pick the size: Choose a press rated above the force needed.
- Support the work: Use the plate slot and a support block under the part.
- Align: Start the part square, with a chamfer or pilot.
- Lubricate: Light oil.
- Press: Pull the handle smoothly.
- Feel: A sudden rise in effort means cocking or wrong fit.
- Check: Check that the part is seated.
Worked example: mechanical advantage
A 12 in handle on a pinion with 0.75 in pitch radius gives 12 ÷ 0.75 = 16:1. A 50 lb pull gives about 50 × 16 = 800 lb at the ram, less friction. Compare that with the press rating and the expected press force.
Broaching keyways
Use a bushing and shims; push the broach through in one stroke per shim.
Arbor vs hydraulic
An arbor press gives feel; a hydraulic press gives much higher force.
Worked example: pressing a bronze bushing
A bushing with 1.0015 in OD into a 1.0000 in bore has 0.0015 in interference. Chamfer the bore edge about 0.020 × 45°, oil both parts, and support the housing on a plate with a clearance hole. Press with a stepped pilot so the bushing cannot cock. After pressing, the bushing bore shrinks by roughly the interference; check it with a bore gage and ream if it is under size.
Ratchet vs plain lever
Ratchet arbor presses let you reset the handle for more stroke at the same leverage. Plain lever presses give the most direct feel.
Push pins out
Use a pin punch or pilot slightly smaller than the pin, and support the part close to the hole.
Common problems
Cocked bushing: no chamfer. Galling: no lube. Broken broach: too big a bite.
Worked example: pressing a bushing
A bronze bushing with a 1.000 in nominal OD going into a housing bored 0.9990 in has 0.0010 in interference, in line with the common shop rule of thumb of roughly 0.0005–0.001 in per inch of diameter for light press fits (check the drawing or the bushing maker first). After pressing, the bushing bore closes by roughly the interference, so a 0.750 in bore can end up around 0.749 in; plan to ream or burnish if the shaft fit matters.
Pressing bearings: which ring to push
Push only on the ring that is being fitted. Pressing a bearing onto a shaft: push on the inner ring with a tube sized to the inner ring face. Pressing into a housing: push on the outer ring. Pushing through the balls brinells the races.
More common problems
Part goes in crooked: no lead chamfer or the ram is not square to the plate. Galling: dry fit; use press-fit lube. Plate slot too wide: support the part on a ring or parallels so it cannot tip.
Tips
- Broach: keyway broach.
- Hydraulic: hydraulic press.
- Bore: bore gage.
FAQ
What is an arbor press?
A manual lever press.
How is force calculated?
Handle length ÷ pinion radius × pull.
Can I broach with it?
Yes.
Arbor or hydraulic?
Arbor for feel and small parts.
Why lubricate?
To prevent galling.
Related guides and calculators
- Metric dowel pin chart (ISO 8734)
- How to Use a Keyway Broach
- How to Use a Hydraulic Press for Assembly
- How to Use a Dial Bore Gage
- How to Deburr and Break Edges
- How to Cut a Keyway
- How to Grind a Lathe Tool Bit
- How to Use a Center Gage (Fishtail)
- How to Use a Rotary Broach
- How to Calculate Press Fit Pressure and Pressing Force
- How to Shrink Fit a Part (Heating Temperature and Method)
- All free machinist calculators
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