Quoted from mark532011:Got my first EM a little while ago. The backglass looks like mint, I am amazed by it. My question - should I spray triple-thick on it just to preserve it or is that only needed sometimes amd I am just asking for trouble?
Depends. Is this "Krylon" Thriple Thick? Recently we had a post about a bad experience from someone using what he said was Rustolium Thriple Thick. And none of us knew that it existed.
I still have a few cans or the original Krylon from a case I bought 15 years ago. You never know when they will change the recipe.
To the original question, I would say yes. Unless you have this pin in a nice climate controlled area the will never experience temperature or humidity change.
Read up on putting a few business cards on the score window and shooting a few thin coats on the back.