Hi Scott,
I think that although the endmill gear cutter is a brilliant device it is in many ways very impractical to market. A supplier could, for example, hold a thousand in stock and yet it is unlikely than any one would be suitable for the particular gear a manufacturer is intending to make. This is because the gear tooth profile and, more importantly, the shape of the gap between the teeth (and therefore the final shape of the endmill cutter) will be different for any given diameter / number of teeth and the contact angle of the gear (the portion of the involute curve forming the tooth profile is always linked to the pitch circle diameter of the gear). The picture below, perhaps rather extreme, shows to illustrate the difference in teeth profile between two gears which both have the same D.P. but differing number of teeth and therefore diameter. The endmill gear cutter could, I think, only really be a product ‘made to order’ once the size and parameters of the gear has been established and then another endmill gear cutter would have to be ordered for the meshing gear (if it was not identical to the first) and so on.
If you are up for a challenge and plan to try making one of these endmills then just as a suggestion:- An online gear profile generator can be found here
http://woodgears.ca/gear_cutting/template.html once you have entered your parameters download the gear in HPGL. From the resulting file delete the first part (up to the second instance of SP1) it can then be opened into LazyCam. By deleting the unwanted chains and entities you will be left with the profile of ½ a tooth – from which you could produce the GCode toolpath for the exact shape of the endmill cutter. Milling it is another task (but not impossible) then cutting the flutes and creating the clearances from the cutting face could then be accomplished (4th axis would be nice here) followed by a hardening process. Sounds like quite a major project but it would not be beyond the grounds of possibility.
Incidentally I am no expert on gears, my only experience comes from profile cutting countless gears and escapement wheels for a friend of mine who has an insatiable appetite for designing and building wooden clocks and mechanisms.
Best of luck with the project.
Tweakie.
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