Ammonia Dangerous to Stained Glass?
I read in your article on Copper Patina to use Ammonia to clean the glass. My glass teacher told us NEVER to use ammonia based cleaners on our stained glass (though I don't remember why). Do you know what harm ammonia could possibly do? Can it possibly be overdrying to the adhesive in the foil? Also, your technique calls for pouring the patina onto the glass - my teacher taught us to apply it with a Q-tip and to never let it sit on the glass itself very long because it could permanently remove irridescence or stain the glass. Have you ever found this to be true?
There may well be a reason for not using ammonia on glass, but I believe that is in referrence to ammonia based glass cleaners (like Windex) that don't get rinsed off. The sudsy ammonia is rinsed off immediately after use. It is not left on the glass. I have never seen any evidence of problems after using it.
As for pouring the patina on the glass, you will notice that I don't use an excessive amount, and it gets wiped off as soon as it has reacted with the solder. It isn't left to dry on the glass. If it were, then you would have problems with it staining the glass, plus you'd then have to wash it off which puts water on the patina and causes more problems further down the road.
My tutorials are all based on my tried and true techniques that I have taught to 100's of students over the years. They are techniques that I know work, but they are not the only way to accomplish the same end results. If you went to 10 different instructors, you'd find 10 variations of any technique and each instructor would feel that their way is the best way.
I certainly don't want anyone to do something they think is totally wrong. That is not the intent of this web site. So, if you are not in agreement with anything you read here, please don't do it. Follow what your instructor tells you.