Sierra Glass

Originally posted July 12, 2007. Now with pictures.

Took a couple of window screens in for repair this morning. While I was there I asked them to fix the side view mirror on the van. They had replaced it several years ago when the original had fallen off. It took them about fifteen minutes, but the next day the silver backing in the center of the mirror became discolored. It looked like the glue had reacted with the mirror coating.

It was ugly, but it still worked, so I didn't bother to get it fixed. But when I was there this morning I thought I might as well get it fixed. When the old mirror was pulled off we were surprised to see that the glue had been applied all around the outside of the mirror, but that the center where the silver backing had been damaged was completely clear of glue. Matter of fact, the glue defined the boundary around the damaged area.

However, the glue did not go all the way to the edge of the mirror, and the uncovered area around the outside was undamaged. Best we could figure was that the fumes from the glue were trapped by the glue all around it and the fumes are what caused the damage. Around the outside the fumes were free to escape, so there was no damage. How about where the glue actually contacted the mirror? Well, that is a puzzle. They used silicon glue, which is the wrong kind of glue to use for this application. This time they used glass mastic, whatever that is. Still only took about fifteen minutes, and there was no charge. Very nice.

Update December 2016 replaced missing pictures.