I’ve never had a problem painting glass. My biggest problem with glass has always been trying to keep paint off of glass.

About guitars and Old World French Polish. This is probably not something you would want to do, but there is a web site that can tell you a lot of details about it. I don’t care for some of the techniques they use, but this is an art and everyone has their own way to doing things. These people had the same problem that I had while learning , and no amount of reading will teach you how. I use a similar method on some of my radios of the 1920’s.
http://www.milburnguitars.com/frenchpolish.html

I talk a lot about radios, but don’t usually give advice. However, there is one piece of advice that I have given to many people that are learning to restore radios. You have redone the finish on two of your radios. If you are proud of what you did, then to hell with what anyone else thinks about it. It’s your radio and you can do anything you want to with it. If you are not proud of what you did, then you will learn to do better.

I can’t really tell you what kind of spray gun to use for small projects. I have used Binks equipment since 1955, including pot guns and heated pot guns, but have learned to use their regular hand held gun for most small projects. They make guns that are smaller, but all their equipment is expensive, and I have not been able to justify that expense for no more than I would use it. I bought a cheap imitation of a small one several years ago, but threw that thing away.

I have a 2hp portable compressor at home where I do most of my radio work, and it is more than enough to take care of a spray gun. But like I said in an earlier post, I often use a Preval for small projects, especially anything that would be a little too clumsy to use a Binks. But then, I have been using point and shoot spray bombs since they first became available, and can usually do a pretty good job with them too.