Repair of Copilot side Front Cap Bracket

[RWDMLD18]

2008 Winnebago Vectra FD
38500 Miles

The adhesive that holds the right front cap bracket next to the head light came loose. Made a bad noise going down the road. The adhesive that Winnebago use back then was Plexus. My nephew does body repairs on antique cars. He recommended Fusor. I called the LORD Mfg. and talked to an engineer and told her that I need to bond painted steel to fiberglass. LORD engineer recommended Fusor T21. T21 has a 45 minute working time. This will allow time to apply the T21 to the attaching areas and install the bracket and clamp. To prepare the area for the T21, I use a air power drill with course sanding disks. Removed the old Plexus down to the fiberglass. This made a acceptable bonding surface for the T21. I do not know is the T21 would bond the the Plexus. Cleaned all dust from surface area to be bonded. I used rubbing alcohol. Note, the picture were taken prior to dusting and cleaning with alcohol.

Side note, My Nephew does body repairs and uses the Fusor adhesives. He told me the it is the best adhesives for bonding metal and fiberglass and composite.

The pictures are from start to finish

[Teamfoxy]

Plexus is a methacrylate adhesive often used because the bond is good and the working time is usually pretty quick so that joints don't need a lot of clamping time. Fusor T21 is an epoxy. Epoxies are very good adhesives and usually have longer working times and need to be clamped (or fastened) in place for longer periods. Neither needs a lot of clamping pressure and both will tolerate a fairly large gap.

The failure in most adhesive bonds to fiberglass is not the adhesive used, but the fiberglass you are bonding to. Fiberglass itself will pull apart at about 900 psi. Usually the failure occurs due to fatigue over a long period of time.
There is also a difference in the rate of thermal expansion between the metal, the adhesive, and the fiberglass which breaks down the joint over time. The best adhesive is one that is somewhat flexible and allows the materials to expand and contract without breaking down. Some amount of gap (usually 3 to 5 mm) is actually desirable.
It is interesting to note that in some of your pictures, the metal parts have holes that allow the adhesive to flow through the metal part which diminishes the reliance on actually adhering to the metal itself.
Basically, the joint has to be designed with consideration for all the factors involved and have enough contact area to allow for fatigue. If you don't, the even the best adhesive will fail.

[rgvtexan]

Some info in this old post, and a clamping idea.

http://www.winnieowners.com/forums/f...ad-315842.html

[RWDMLD18]

Photo 5 and 6 with the oozing is the completion of the repair. I used bunny straps to hold the Cap aganst the bracket.