Bob Jude wrote:

<The first few hours of flight after the mod., I saw some grease/oil
streaking but attributed that to residual grease.>

I'm not certain about your experience, but have seen many instances where
corrosion products of the aluminum hinge washes out on the control surfaces.
It's unsightly and looks like grease'; in reality it is black aluminum oxide
powder. More importantly it is evidence that from the get-go the hinge is
getting more and more loose.

A hinge that would not corrode or get looser over time would be a benefit.
In fact a hinge that had a snug fit initially and always would be better
than the aluminum hinges available.

I suggest a solution to overcome the  problem - Carbinge.

Shameless commercial note, but a helpful response to your posting as well.

Regards,

John Barrett, CEO
Barrett/Garrett Enterprises, Inc.
PO Box 428
Port Hadlock, WA 98339
www.carbinge.com