It seems to vary quite a bit, not sure that I’ve lost a full 1/4 but could be, I didn’t measure after. I will next time and I’ll let you know what I find out.

Are you sure they were a full 10" when you bought them? I have found that the few pre cuts I've purchased were almost always smaller than stated size, so I don't buy them unless on deep discount.

I lost 5/8" when I washed my layer cake. Only on one side. They are 9 3/8" by 10" now.

That's one reason why I don't care for pre-cuts, shrinkage. They're going to shrink either before you use them when you wash and/or starch them or after you've put them into a quilt. So which would you prefer........they shrink now or later? I've found my pre-cuts more times than not to be mis-cut even beforehand so rather go for yardage and do my cutting after I've starched them. Most of my 5" and 10" are usually off by .25" anyway so I just cut as much out of them as possible and call it good. Trying to use all that I have on hand to get rid of them.

Fabric shrinks when wetness is applied; it doesn't matter what form that wetness is, water, steam, starch or Best Press. Personally, I prefer the shrinkage to happen when I wash the quilt after construction. The batting also shrinks. However, if unwashed fabric is used the crinkly look is somewhat minimized which I like. I also dry the finished item flat on the floor using a painters drop cloth (plastic sheet) to protect the floor. There are so many variables to deal

I think it is anything with moisture in them, I have had it happen with just a steam iron. You might avoid it with just a hot iron, no steam or starch. I learned this the hard way when I used unwashed fabrics, cut them to size then starched the pieces before sewing—-nothing was the original size.

About all I buy are pre cuts. I rarely use the 10 inch squares as it but cut them down to the size I want. I starch and steam the pieces before cutting. It's so much easier to store the big stacks of layer cakes then yardage. The solid color layer cakes are my basics. The beautiful prints all from one design are in one package. I get motivated walking in my sewing room and seeing the baskets and shelves full of pre cuts. Layer cakes, jelly rolls, charm packs, fat eights, fat quarters, mini charms, and all the rest. So nice.

THanks for all the great advice! I just wish I had know that the shrinkage occurs on one side only so I could have matched the pieces up better. I will try some of the great ideas you all have given me! Thank you!

So I'm wondering , if I'm OK with the shrinkage from steam or ironing, does that mess up more intricate patterns since you no longer have a,perfect square? I've only done simple patterns so far, like diamonds or easy stars.

No, it is a starch. Calling it a "starch alternative" doesn't mean it's not starch, it means it's an alternative to the traditional starches such as Sta-Flo and Niagra. It is simply a marketing ploy. They do clarify it so it's clear, add surfactants that help it sink into the fabric clearer, and make it smell pretty. The bottle that I have states very clearly it is starch, and if you do a Google search for Best Press MSDS, you will see that it is listed as a starch.

MSDS = Material Safety Data Sheet. Required of manufacturers by the federal government for any solution, solvent, etc.