Bob Purcell of Superior Threads has the answer for you:

http://www.superiorthreads.com/education/general-thread-information/how-much-thread-does-it-take-estimate-how-much-thread-you-will-need

If you aren't already on his email list, get on it. Each newsletter is a learning experience!

JoAnne

I use cones of thread so I have never been able to tell how much I use. It really depends on how heavy the quilting is as to how much thread you will need.

Barbara

I ran through 2-3 spools of 500yard thread to quilt my GS quilt. Is that typical usage .. it was a throw size quilt.

I am wondering as I want to do more machine quilting in the future ( without running out of my thread) and am wondering how much thread should I buy to machine quilt an average size quilt.

anna