How can I cut a large spur gear with a prime number of teeth?
As you probably already know, prime spur gears on most gear cutting equipment require a change gear with the same prime number of teeth. For small prime numbers (less than or slightly larger than 100 teeth), you likely have a change gear. If you have such a change gear for your hob machine, then the index change gears are in the ratio INDEX / PRIME NO. OF TEETH. If you have a differential machine, and the machine uses feed change gears, it is not necessary to have the same teeth in an index change gear. Once again, the machine cannot use a dial-set hydraulic feed table drive. You can superimpose two setups on a differential machine. (CPC-HOB Vers. 2.4 does this in its DUAL setup option.) The first is a set of differential change gears that will generate any helical angle on the gear, say 15 Degrees Right Hand. The second setup treats the same machine as “non” differential, which will require synchronized index and feed gears calculated to yield a 15 Degree Left Hand gear. When you put
As you probably already know, prime spur gears on most gear cutting equipment require a change gear with the same prime number of teeth. For small prime numbers (less than or slightly larger than 100 teeth), you likely have a change gear. If you have such a change gear for your hob machine, then the index change gears are in the ratio INDEX / PRIME NO. OF TEETH. If you have a differential machine, and the machine uses feed change gears, it is not necessary to have the same teeth in an index change gear. Once again, the machine cannot use a dial-set hydraulic feed table drive. You can superimpose two setups on a differential machine. (CPC-HOB Vers. 2.4 and later have the DUAL setup option.) The first is a set of differential change gears that will generate any helical angle on the gear, say 15 Degrees Right Hand. The second setup treats the same machine as “non” differential, which will require synchronized index and feed gears calculated to yield a 15 Degree Left Hand gear. When you pu
