illinois

Well, this topic sure got off the question, didn't it? Hey, I remember the 70s and 80s. That was an era of poly blends and before quilters thought they didn't need to be purists in what they used in their quilts. They used what they had and some of those poly blends were nice. Unless you find the plates to be unacceptable to be handled (dirty or too smelly), I'd look at them for what was used and, if they are not something totally out there, I'd put them on a background of a size that is pleasant to you and quilt it before washing. Once that is secure on the background and quilted, it probably isn't going to shrink appreciably. As to background size, I agree with those who have mentioned what you want to do with the "blank" space and sashing, considering the size you hope the quilt to be. Congratulations on the rescue of these and wanting to finish your mother's work. She will be pleased to be looking over your shoulder! Wow--60 of them!! (Again, I recommend not washing until those plates are stabilized. You may end up with them falling apart.)