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Unread 05-11-2014, 00:31
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asid61 asid61 is offline
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Re: pic: 4143 offseason motor in wheel swerve

Quote:
Originally Posted by RyanShoff View Post
You are correct the wheel is an assembly in the cad. This is really one piece. We have parameterized Creo involute gear files. It was being lazy that the wheel was modeled separately and 'glued' to the gear. It is designed to be made as one piece out of 4" OD .5" wall 6061 pipe.

There is a machining process called gear shaping. It is not too common any more but is still about the only way to form a gear up against a shoulder. This article describes the history of process. Here is the first random video I found.
There are in fact many different ways to shape gears, as well as hob them. For internal gears it is advisable to shape instead of hob, and their profile makes it very difficult to shape them properly (espcially in your usage context). The style of shaping you linked to is difficult for gears that go up to a shoulder. I would only be comfortable using an internal gear rotary broach to broach up to a shoulder, and you would have to make that tool yourself.

Your sponsors may not have the correct technologies to produce internal gears. Any mill can make external gears, but internal gears are far more difficult to create, and even more difficult if they have shoulders. Make sure your sponsor can make these gears before going any further. If they cannot, just bolt a pre-bought internal gear to the end of the assembly instead.

I do like how it's designed to be made out of 4" stock tubing though. Very clever.
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