On Mon, 24 Jun 2013 12:25:22 +0100, Muddymike wrote:

It would seem that the locating hole had originally been drilled in the
wrong place only allowing the first 5 mm of the spline to engage, hence
the wear.

Or a safety feature, spline strips if a tool seizes.

TBH I think your explanation or incorrect assembly (tube on
backwards?) is more likely. B-)


--
Cheers
Dave.