Hex Nut Chamfer

[chris54]

This has absolutly nothing to do with Inventor, but I have found no answers elsewhere...

What is the purpose of the 30 degree chamfer on hex nuts?  I've been told it's to help a wrench drop on.  I've also been told that if the chamfer is not machined on the the side contacting the metal/washer, the nut will tend to loosen faster then if it had the chamfer.

Any of this make sense?  Is there a source out there for this inane kind of data???

[blair]

The top side wrench/socket drop sounds plausible. The underside I was told reduces any galling when the nut is tightened. The same with flat washers, there is a correct mating side with the bolt.

If you look carefully, the top side of a flat washer has a small radius from the stamping process. This should mate with the bolt head to help reduce any scoring of the root of the bolt shaft and bolt head.