09/25/2026
Proper alignment is critical for maximized gear set performance. In preparation for assembly of the gear set, the housing should be inspected using the following guidelines.
The center distance, “A” dimension shown below, should be within ±0.001 inch per inch. (For example, a 3.000 inch center distance would have a tolerance of ±0.003 inch.)
The alignment of the bores, which will locate the pinion and gear, should also be checked. The shaft angle (usually 90˚) should be within ±5’. Deviation from the nominal shaft angle will cause a contact pattern shift between the assembled pinion and gear. Heavy localized contact toward the inner or outer band of gear teeth is not desirable.
Read more here: https://www.spiroidgearing.com/faq/assembly-mounting/