need to giggle actinic bulbs

[Bob I]

I have had tubes that have had to be rubbed a bit but these have to be turned to "just the right spot" and they will come on. Has anyone had this problem..and equally important does anyone know how to fix it?

I read in an old textbook of mine (Applications of Electrical Construction) That some of those bulbs require a metallic shield above them to work properly. It has to do with picking up a required ground. I had the same problem many years ago with 30" bulbs. They always needed rubbing.