need to giggle actinic bulbs

[rossb]

I have two 30 inch actinic T-8 bulbs in my lighting hood. They are in standard 30 inch home depot flourescent single bulb fixtures. (about 4 weeks old). when I initiall installed them they worked fine. I did some modifications on my lighting hood (kind of shook them all up) and now to get them to work I have to giggle them.

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?