When I wash a rag quilt, I run it through the dryer for 10 minutes first, to get the loose threads. then I wash it. In the washer, I open the lid often and scoop the threads off the top, in both the wash and rinse cycles. I get a lot of threads that would otherwise go down the drain. I also wash (and scoop threads) three times before I put it in the dryer. Then I check the dryer vent every ten minutes. Hope this helps someone.