Wexmar provides custom gear blank machining for gear shops, gearbox builders and OEMs that need accurate blanks ready for tooth cutting. Our Canastota, New York shop produces CNC machined gear blanks on Mazak and Doosan lathes, with hubs, bolt holes and keyways added by live tooling or on horizontal machining centers. To be clear about scope: we supply turned gear blanks. Gear cutting, hobbing and shaping are not offered in-house, and when a customer wants finished gears we route tooth cutting through qualified outside processors.
What gear blanks do and who buys them
A gear blank is the turned and bored part that a gear shop hobs, shapes or grinds into a finished gear. Every tooth is cut relative to the blank's bore and face, so blank runout and face squareness carry directly into gear quality. Typical buyers include:
- Gear cutting shops that prefer to buy accurate blanks rather than turn them
- Gearbox, power transmission and pump OEMs managing their own gear supply chain
- Maintenance buyers sourcing blanks for replacement gears
- Defense and government programs with build-to-print gear blank requirements
How our custom gear blank machining works
Turning bore, faces and outside diameter
The bore, both faces and the outside diameter are finished with as few re-chuckings as possible. On our Mazak Multiplex 6300Y the part is transferred between spindles to finish both sides in one cycle, which holds face-to-face parallelism and bore squareness. Larger blanks run on the Mazak Nexus 450-II. See CNC turning.
Hub, web and bolt features
Hub profiles, web recesses and lightening pockets are turned to print. Bolt circles, set screw holes and keyways are cut with live tooling and Y-axis, or on our Mazak horizontal machining centers for larger or more complex blanks. Small pinion blanks up to 32 mm diameter can run on our Maier Swiss-type machines. See Swiss machining.
Shaft-type blanks
Pinion shafts and worm blanks are turned between centers or from a chucking with the tailstock, keeping journals and the gear diameter on a common axis.
Typical gear blank materials
- 4140, 4340 and 8620 alloy steel for through-hardened or carburized gears
- 1045 carbon steel for general-duty gears
- Bronze for worm wheels
- 303, 416 and 17-4 PH stainless for corrosion-resistant gears
- Aluminum and engineered plastics for light-duty and instrument gears
Critical blank features and how we hold them
- Bore size and fit: bored to the arbor or shaft fit, often with a tight size band so the gear cutter can locate on a mandrel.
- Face runout to bore: the locating face is cut with the bore so the blank seats square on the hobbing fixture.
- Outside diameter to bore runout: the tooth circle starts true to the bore.
- Face parallelism: both faces finished from one datum so stacked blanks cut consistently.
- Stock allowance: OD and face stock left to your gear shop's specification if they finish-turn after heat treat.
Typical tolerances and finishes
| Feature | Typical tolerance | Tighter on request |
|---|---|---|
| Bore diameter | +/-0.0005 in | +/-0.0002 in |
| Outside diameter | +/-0.001 in | +/-0.0005 in |
| OD radial runout to bore | 0.001 in TIR | 0.0005 in TIR |
| Face axial runout to bore | 0.0005 in TIR | 0.0003 in TIR |
| Face parallelism | 0.001 in | 0.0005 in |
| Bore and face finish | 63 Ra | 32 Ra |
Values are typical and depend on blank diameter, width and material. The quote confirms each callout.
Design notes
Blanks cut better when the drawing names the bore and one face as datums and states runout limits relative to them. If your gear shop cuts teeth on stacked blanks, say so, since face parallelism then matters as much as runout. For carburized gears, tell us whether stock should be left for grinding after heat treat. Forgings or bar are both workable, and forged blanks can be sourced through qualified outside processors.
Secondary operations
Normalizing, stress relief, through hardening, carburizing and nitriding are completed through qualified outside processors. Gear hobbing, shaping and gear grinding are also routed through qualified outside processors when finished gears are requested.
Quantity patterns
Gear blank orders range from single replacement blanks to production runs of several hundred per release for gearbox builders. Programs and soft jaws are retained for repeat blanks. Related parts include hubs and yokes.
Inspection
Bore, runout and parallelism are checked with bore gages, indicators on a mandrel and our Brown and Sharpe CMMs. FAI in AS9102 format, CMM reports, material certs and heat-lot traceability are available.
Getting a quote
Send the blank drawing, material, heat treat plan and quantity. You can upload a drawing for an instant estimate, and an estimator will confirm price and lead time. Call (315) 400-2654 to discuss gear blanks.