Considering the MMSG ground spiral family? It is listed separately from MMSGQ and SMSG.

Customer: What distinguishes this family?
KAYO: MMSG is listed as ground spiral miter gears in the KHK range. The manufacturer identifies the material as SCM415. Miter gears are used where a change in shaft direction is needed with a 1:1 tooth-count ratio.
Customer: Which sizes are listed?
KAYO: The current Japanese selection table shows 30 model codes. Modules: 2, 2.5, 3, 3.5, 4. Tooth counts: 20, 25, 30. Representative dimensions are shown below, followed by the complete model list. Mass is stated in kilograms.
| Model | Module | Teeth | Outside diameter (mm) | Mass (kg) |
|---|---|---|---|---|
| MMSG2-20R | 2 | 20 | 42.7 | 0.14 |
| MMSG3.5-20L | 3.5 | 20 | 74.53 | 0.51 |
| MMSG3-25L | 3 | 25 | 78.78 | 0.65 |
| MMSG2.5-30R | 2.5 | 30 | 78.04 | 0.66 |
| MMSG4-30L | 4 | 30 | 124.7 | 2.49 |
Customer: How should I select the mating gear?
KAYO: Specify an MMSG mating model with the correct opposite spiral hand; do not choose a different family by module alone. Module and tooth count are only part of the selection; the tooth system and assembly geometry must also agree. Use the manufacturer mating guidance for the exact family.
Customer: What are the exact model numbers?
KAYO: MMSG2-20R, MMSG2-20L, MMSG2.5-20R, MMSG2.5-20L, MMSG3-20R, MMSG3-20L, MMSG3.5-20R, MMSG3.5-20L, MMSG4-20R, MMSG4-20L, MMSG2-25R, MMSG2-25L, MMSG2.5-25R, MMSG2.5-25L, MMSG3-25R, MMSG3-25L, MMSG3.5-25R, MMSG3.5-25L, MMSG4-25R, MMSG4-25L, MMSG2-30R, MMSG2-30L, MMSG2.5-30R, MMSG2.5-30L, MMSG3-30R, MMSG3-30L, MMSG3.5-30R, MMSG3.5-30L, MMSG4-30R, MMSG4-30L.
Customer: What should I check before installation?
KAYO: Confirm mounting distance, shaft alignment, bearing support and backlash. Check the contact pattern during assembly and choose lubrication suited to the selected material and operating conditions. Evaluate the load rating against the actual speed and duty.
Customer: What should I send for an enquiry?
KAYO: Please share the complete model code, quantity, mating gear, shaft angle, bore and keyway requirements, operating speed and load. We can discuss the specification and availability for your application.
References: MMSG official model selection table | KHK miter range. Confirm final dimensions and suitability against the latest manufacturer drawing.










