Considerations when selecting hobs

Considerations when selecting hobs

1, Bore Dia.: using standard table(caution: tolerance of inch and metric)

2,Outside Dia.: usually using the standard table, however Outside Dia. can be increased for increasing productivity and fewer interruptions of maching( for high auto motive volumes: for M2.5, bore Multi-Gash(17-20N)

3,OAL(overall length): Per Massive volume, OAL can be increeased for up to maximum of Machine shift amount.

4,No. of Thread, select threads depending on cut type finishing.

5,No. of Flutes: Use 1 thread for Finishing Cutting, and use multi thread for roughing, or semi-topping.(When the number of gear teeth is divisible by no: threads, a profile error may result.)

6,Rake angle: Normally don't need.

7, Hand: Same direction as gear's.

8,GL: If hob lead angle is over 5 degrees, use spiral gashes.

9,Class: Normally use DIN A(Gear: JIS4-5)

10, Material: If high speed of hardness is required, Powder Material is used. Otherwise, M35(SKH55) is used.