The thread for hand quilting and the thread for machine piecing are actually wound differently, which is another reason you don't want to use hand quilting thread in your machine. I think that's what causes all the dust, though I am not 100% positive. I do know that using hand quilting thread in your machine will cause frayed threads and will result in a lot of breakage, which is highly frustrating!! I learned that many long years ago, before I knew any better. :roll:
Piece ~ Tiffany