I know this has gone about a few times, but...here's proof. I pre wash EVERYTHING. Habit from years ago when you HAD to pre wash everything. I know these days, fabrics are a better quality and often don't need pre wash for shrinkage and bleeding issues, but some habits die hard and I pre wash as I dont' want to take the chance of something shrinking or bleeding and ruining something I just spent weeks working on!
Anyway, I bought some charms before I realized I didn't like using them.... some time ago. I was working on making placemats and needed squares, so I took this pack of MODA charms of rustic colors. They were 5" squares. As they hadn't been pre washed.. I placed them into a lingerie bag and pre washed them. 100% cotton shrinks, no matter what anyone thinks!
I take them out, press them and voila! Each charm shrunk about 1/2 inch one way and about 1/4 inch the other way. Here is the picture....the ones on the bottom are charms that have NOT been pre washed...straight out of the package. The solid on top is the pre washed charm.. and as you can see...shrunk.
So... this means....that if you dont' pre wash the charms, once you make your quilt and do a final wash...the quilt is going to shrink 1/2 inch per charm used. If you dont have a concern about the finished size, I guess, no problem. But if you want a specific size....you'd either better pre wash and go from there, or make sure you add at least 2 charms length both ways to accomodate this shrinkage. Plus...now these charms are not 5x5"...they are 4,1/2x4,1/2-ish"...so you now need to use that as you starting cut size if you are using other squares/fabric with the charms. And you would get a great crinkle look ...if that is what you like.
My question tho is this...if I use charms that are NOT pre washed, with charms or yardage the HAS been pre washed...what would the final washed quilt look like? Partly shrunk, partly not? Pre wash flat, not washed crinkled? OR would the crinkle pull the pre wash and make it wonky? What do you think... or know?
Just thought I'd share this.