Originally Posted by quiltinggrandmaca
When using the spray for basting do you still have to tape down the backing before you put the batting and the top together?
I don't.
I smooth the batting out on a large flat sheet on the floor (to catch any overspray), then smooth the backing fabric out on top of the batting. When it is the way I want it, I fold back the fabric so the top half of the batting is exposed, spray the batting, then smooth the fabric back in place. Then I fold up the bottom half of the fabric and repeat the process. I flip the quilt sandwich over so the other side of the batting is up and repeat the whole process with the top. That's it, except for tossing the large flat sheet into the laundry basket.
I would not use a 5-year-old can of basting spray. You don't know what chemical changes may have taken place over time. I recommend buying a new can of 505 basting spray.
What kind of batting are you planning to use? Nobody has problems with cotton batting, or 80/20 batting. Some people have problems getting polyester batting to adhere; however, that may be due to the brand of basting spray being used. I don't think anyone has reported a problem with polyester batting when they use 505.