Posted by Sp on August 18, 2009 at 07:22:47:
In Reply to: Re: Hob Tip Radius posted by Colin on August 17, 2009 at 11:03:44:
As far as I know: the transition curve, located between the root radius and the involute flank, would change its shape when the tip radius of a hob is changed. The point where the transition curve meets the involute flank is located very close to the form diameter. So if you have the required form diameter you can enlarge the hob tip radius until the the required form dia. is reached (with some margin left of course) and therefore get a stronger gear.
The tools are usually made to standards, so no need to discuss the hob radius. If you optimise a tool the way described above, it will not be universal and you will have to check every new gear to see if it fits. A standard is a balance.