Originally Posted by Maia B
It DEPENDS ON THE THREAD!!! Sorry to shout, but you might quilt with super fine silk and a 70 needle, or thick thread and a 100. The Superior Threads site has excellent, thorough info on this. Using a needle that's too small for your thread will cause shreds and breaks, too big and you are putting big holes in your fabric for no reason. It's like asking, "what size pants should I buy?". It's going to depend on what you are trying to squeeze in there :).
I agree. I've rarely changed needle size just because I'm quilting as opposed to piecing.
I also make a practice sandwich EVERY TIME I begin to quilt. I practice with the same fabric, batting, thread, needle and to a certain degree the pattern that I'm quilting (or at least a small portion).
I've quilted and thread painted with a 70 using a high quality 50wt thread with no problems.
Another word. 50wt isn't always the same "thickness". A 50wt Superior, Aurifil, Mettler, or Gutterman is much thinner than a 50wt C&C or Connecting Threads. I believe it is dependant on the staple length used to make the thread (I'm referring only to cotton thread). So you can't just go by the weight ... feel it and use it.