Monday, May 26, 2014

The invisible cure: Using UV activated glue for vent window catches

One of the problems many Dino owners struggle with is properly bonding the metal catches on the front vent windows. Knowing this to be a problem we investigated a number of adhesives that would offer a reliable bond. Sticking metal to glass is never something that is easy and on the vent windows things are further complicated as the glue join is under quite a bit of tension from the spring effects of the molding rubber that surrounds the vent window. In the end the solution came from our neighbor Joe who offered us a high strength adhesive made by Loctite and cured using the invisible powers of UV light. He supplied us with the glue, curing lamp, and requisite yellow safety glasses (that make our Dino disappear)


Before trusting the glue on the car we ran a test using a scrap piece of glass and an extra mount we had. The cool thing about the adhesive is that it cures in about 90 seconds.


Once dry we administered the most un-sophisticated durability test we could muster. With the glass held in a vise we hammered and hammered until the bond or the glass broke. In the end neither failed as we just could not grip the thick piece of glass we had tight enough to keep it from moving however with the metal mount deforming and starting to bend we were pretty sure we had the glue for the job.


Now for the real thing. We carefully located the mount on the vent window using a black piece of decal material with a perfect hole cut in it. The decal served 2 purposes. One is that it really helped locate the pin well and second because no light goes through it, all of the overflow glue stays fully liquid making for a perfect masking. When the light is turned off all you need to do is pull the decal away and there is no mess or leakage to clean up. To be honest we tripped over the second benefit totally by accident but it was very welcome and a tip worth sharing.


Lastly here is the finished assembly. Ignoring that everything is covered in fingerprints and could use a proper cleaning, another job is removed off of the list :)

4 comments:

  1. Did you replace your vent window rubber seals with new? Mine are quite hard from age and no way would the latches stay on if I tried to secure the vent windows. And the bad thing is that every time the latch comes off, typically it takes a little bit of vent window glass with it, creating a divot in the glass.

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    1. We did replace the vent window rubbers with new however the new rubbers are crazy expensive and then require DAYS of trimming and fitting to get them to work. If your original rubbers are ok leave them in or get ready to spend by the bucket loads to get the repros to work correctly. If you are at the stage where you have a divot in the glass it will be necessary to replace the glass in order to get a proper bond. Once the glass develops a divot the glue no longer works properly and will fail quickly.

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  2. I'm curious: what did the factory use for this? I don't think UV-cure epoxy existed at the time these cars were made but there is one other alternative: indium solder. Ford used it at one time for attachment of rear-view mirror mounts to the windshield and this goes back about 50 years. One property of indium solder is that it does stick to glass and metal. It should be strong enough for this type of service.

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  3. The indium solder route is very interesting and I cannot comment 100% as to what the factory used. The nice thing about the UV cure glue is that it gives a perfect and invisible bond. Attachment glues normally can be seen on the backside and the UV stuff is optically clear making for a much cleaner look.

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