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Unread 03-10-2008, 08:21
ajlapp ajlapp is offline
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Re: Hex Shafts and Bearings

Quote:
method which involves broaching bushings to the size of your hex and then putting that on the shaft to go in the bearing
The method mentioned above is the cheapest and fastest way to pass a hex through a round bearing. Oversize your bearing id to accept a bronze bushing with suitable side wall. Then broach the bushing to use as a sleeve for carrying the hex.

You can also find something like this. Though I do not know of a source that stocks these.

Some notes about hex shaft from a former "hex only advocate." In applications where backlash and precision are a concern, say in an arm joint assembly, hex shafts can be less then desired. A broached hole is quite accurate, but hex stock has uncontrolled dimensions and may provide a loose fit.

Milling your own hex onto your shaft will allow you to control the fit precisely, but this requires more machining capability and diminishes the main 'ease of use' advantages.

For drivetrains, where lash is not a huge deal, hex is the way to go......

Also, precision ground keyed stock is readily available and keyway broaches are cheaper than hex broaches.

Good luck.
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