If you are worried that the action of the washing machine is too much, I will 'wash' them in the bathtub. My mom and I used to do this alot with the quilts/fabrics/linens that she picked up at auctions. We used Orvus and tepid water. We would submerse them in the water, swoosh them around gently by hand, drain the tub, gently squeeze, fill tub to rinse (sometimes they needed to be rinsed several times) and then lay in the yard on top of a clean sheet and a clean sheet on top of it. If it was especially old or delicate, we would suspend a tarp about afoot over the quilt to completely block out the sun. We have only had one not survive - that was a velvet and satin crazy quilt that the dealer had 'thrown in' to the batch that we had bought.