Hi Ed

Sorry to hear about the delaminations or I think more properly, disbondings.  How was the joint originally prepared?  I'm always concerened abouyt contamination and like Boeing, I don't allow lubricants into my bonding shop. This is particularly true of silicone.  But what adhesive was used?  There are a number of bonding adhesives that are much better than the Jeffco (if that's what you used).  Also sanding and cleaning is critical just prior to bonding.  I know they say to use industrial grade solvent for cleaning but that has about 3% impurities as I remember.  Reagent grade would be better and a lab towel like a Kimwipe is better than paper towels.

Good luck on the repair!

Dan Newland