45° SHAFT ANGLE

For 1:1 ratio at 45° shaft angle: δ₁ = δ₂ = 22.5°. Used in: some paper handling machine deflectors, angle iron processing machinery. Less common commercially — most bevel gearbox designs avoid 45° because the tooth geometry becomes less efficient at acute shaft angles. Korea Ever-Power produces 45° bevel pairs M2–M6 on order.

60° SHAFT ANGLE

For 1:1 ratio at 60° shaft angle: δ₁ = δ₂ = 30°. Applications: marine steering gear, some agricultural seeder drive arrangements, special machine tool auxiliary drives. The 60° bevel gear has a compact configuration compared to 90° in some machine layouts. Korea Ever-Power stocks M3 and M4 at 60° shaft angle in C45 and 20CrMnTi.

120° SHAFT ANGLE

For 1:1 ratio at 120° shaft angle: δ₁ = δ₂ = 60°. Applications: direction reversal in confined spaces where co-planar shafts intersect at an obtuse angle. The 120° bevel gear pair reverses shaft direction while maintaining a compact crossing geometry. Custom manufacture M2–M8 from Korea Ever-Power in 15–22 days from drawing confirmation.

Can I replace one gear in a worn miter pair without replacing both? The pinion is more worn than the wheel.

Replacing only one gear in a worn miter pair is not recommended for miter gears at any significant duty level, even though both gears are identical and replacement of either is geometrically possible. The reason: a new gear engaging with an old, worn gear partner will not achieve the designed contact pattern from the first operating cycle. The worn gear’s tooth surfaces are not the smooth, accurately profiled surfaces that the new gear was designed to mesh with — the worn tooth flanks have irregular surface profiles from micro-pitting and abrasive wear, and the new gear’s teeth will make contact with the worn surface at different points along the tooth profile than the theoretical contact ellipse. The result: the new gear will wear at a significantly accelerated rate against the worn partner, exhausting its fatigue life in approximately 40–60% of the time it would achieve against a new partner. For miter gear applications up to M3 module and low duty (under 2 hours/day): replacing the more worn gear alone is a reasonable short-term decision if cost constraints prevent full pair replacement. For M4 and above, or at duty above 4 hours/day: always replace both gears simultaneously. Because miter gears are identical, the cost of replacing both is only double the single gear cost — not the higher cost premium that applies when replacing a large and small gear in a non-unity-ratio bevel pair.

What is the correct backlash setting for a miter gear pair and how do I measure it at installation?

Miter gear backlash is controlled by the axial mounting distance of both gears on their shafts — moving either gear axially toward or away from the apex of the pitch cone changes the tooth contact and the backlash simultaneously. The recommended backlash range for miter gears by module: M1–M2: 0.04–0.07 mm; M2–M4: 0.07–0.12 mm; M4–M6: 0.10–0.16 mm; M6–M10: 0.14–0.22 mm. These ranges are the circumferential (tangential) backlash measured at the back cone — not the normal backlash on the tooth face. To measure backlash at installation: lock one shaft and mount a dial indicator tangentially against a tooth on the other shaft’s gear at the back cone radius. Rotate the unlocked shaft through the backlash dead band and read the dial indicator displacement — compare to the module-appropriate range above. Adjustment: move one gear axially toward the apex (reduces backlash) or away from the apex (increases backlash) by adjusting the shim thickness behind the gear hub or adjusting the shaft-to-housing register. Re-check contact pattern after any backlash adjustment — the contact pattern and backlash cannot be optimised completely independently, so iterate between pattern checking and backlash measurement until both are within specification.

What is Korea Ever-Power’s availability and lead time for standard miter gear pairs, and what is the minimum order quantity for catalogue sizes?

Korea Ever-Power miter gear availability by category: (1) Stock items (immediate dispatch): straight bevel miter gears in M2, M2.5, M3, M4 with 16T, 20T, 24T tooth counts in C45 induction hardened and 20CrMnTi carburized, bore 8–50 mm. Standard stock bores are 8, 10, 12, 14, 16, 20, 25, 30 mm — most orders can be shipped within 3–5 working days without minimum order quantity. (2) Made-to-order standard sizes (M1–M1.5, M5–M6, non-standard tooth counts, custom bores): lead time 10–16 days from order confirmation, minimum order 2 pairs (4 gears). (3) Custom miter gears (M6–M12, spiral bevel, non-standard materials including 316L stainless, brass, and MC nylon, non-90° shaft angles): lead time 15–25 days from drawing confirmation, minimum order 1 pair for M6 and above, 3 pairs for M1–M5 custom. Spiral miter gears at M2–M5 are available as made-to-order items in 12–18 days — these are the most common upgrade path from straight miter for customers experiencing noise or load capacity issues with their existing straight bevel miter installation. Korea Ever-Power also provides a free gear selection service for customers replacing worn miter gears of unknown specification — provide the worn gear for measurement (or submit tooth count, OD, bore, and face width measurements) and Korea Ever-Power will identify the module, calculate the pitch cone angle, and quote a matched replacement pair within 24 hours.

Spur Gears

M1–M20 · in-line · industrial drive

Helical Gears

Low noise · compact gearbox · industrial

베벨 기어

Miter 1:1 · 90° · straight & spiral

Worm Gears

High ratio right-angle · self-locking

Ring Gears

Internal · planetary · indexing table

Planetary Gears

Compact · high ratio · servo

Plastic Gears

Nylon miter · dry-run · food safe