GD&T Hexagon Drive

[BulkHandler]

Hello all,

Looking for guidance regarding dimensioning a hexagon shaft connection for a rotary shaft. The shaft will be turned then will have the external hexagon profile milled out on one end.

The hexagon drive will fit a wire cut sprocket manufactured to suit the shaft.

I'm looking to maintain a clearance fit of approx. ~10-40um clearance, i.e. to accurately locate the parts during installation and operation.

In-progress drawing PDF's attached.

http://files.engineering.com/getfile.aspx?folder=df3a5543-9f3a-4978-8ea5-404aa415e92f&file=Shaft.pdf

http://files.engineering.com/getfil...e3e3-4552-9edd-2efd5141abed&file=Sprocket.PDF

I'd prefer to stick with the hexagon shaft connection as it's easy for our chinese fabricator to produce. Square drive isn't an option due to torque requirements and OD limitations.

Appreciate any input.

Thanks,

 

[AndrewTT]

Am I reading the drawing correctly that the total runout FCF is pointing at the inscribed circle of the hex hole on the sprocket?

 

[Nescius]

How about an all-around composite profile tolerance? Complete and separate control of the hex shape itself and its location.