Does fine line masking tape have a shelf life?? I have some that might be 5-6 years old in my shop and the temperature varies from 100 to 25 degrees depending upon the time of year.
 Would this have a bearing on the line not being as crisp as when it was new?  (The paint is bleeding under the tape)

         Thanks for your answers..

 As an in expensive alternative, I use the green masking tape that can be bought at the local auto parts stores. I buy it in different widths and trim it to 1/4 or less to make tight bends. I do lay it down on a bare piece of balsa before laying it out on the model. It makes it less sticky and not as easy to lift underlaying paint. I use this stuff a lot ( on dope finishes) and it makes crisp edges and (knock on wood ) I have not had any bleed unders to date. I have had the same problem storeing my expensive trim tape with heat making a mess out of it.....Gene