I heard some of you use starch to stiffen your fabrics so they don't move as much while cutting and sewing. Have you ever had your fabric shrink while ironing it?
I put together several blocks and started ironing them only to find out that one color had shrunk!!!! I don't have anymore of that material to make more blocks. Am I doing something wrong? I made sure that the iron wasn't too hot, and that I did not iron too long. I don't know what to do. HELP!!!!!!

This tells me the fabric *probably* was not 100% cotton, is this a possibility?
If the fabric had a polyester blended into it, the poly will melt or shrink when overheated.

I got into this issue with my first quilt, because I did not even know about different fiber content of fabrics.

Just a thought.
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I'm a member of a BOM at a local LQS($9-$11pr yd stuff) and they only give you enough fabric to cut your blocks with very little left over (maybe a quarter inch now and then). Since the fabric isn't prewashed I had some shrink HORRIBLY and it was 100% cotton, the buyer had just purchased some cheap fabric to pass off as good stuff. I had to substitute fabric from my stash. SOoooo, what I'm trying to say is that if it wasn't prewashed even cottons can shrink up a lot if it's cheaply made fabric.

Yes I've had 100% cotton shrink while ironing too. I find it's more the darker colors that do this. Could be due to the dye they used.

I just washed about 40 pieces of fabric. Many of them were FQs. Several are no longer FQs. They shrunk so much that some measure at less than 17". I am so glad I washed them first, as now when the finished quilt is washed, there should not be any major puckering.

No kidding wow.
Well I will look more carefully now at my quilting cottons.
I have almost all of it washed, but not all, and I think I'll just go in there and serge all the raw edges and get that taken care of.
Thanks for the heads up all you guys.

Try blocking the blocks to size. Sharon Schamber has some videos on Youtube that show how to do this. Ironically, it involves spraying the block with starch until wet (then pinning to size).

that's exactly why I'm a FIRM believer in prewashing, you just never know what's gonna happen.

What happens to the stretched/blocked blocks the next time they are just washed? Do they revert back to size?

I think if the cloth is prewashed, then it will not change shape again.
That is to say, if the binding, for instance, is starched and ironed prior to applying to the quilt, but is torqued or twisted, looks good at first, but after washing it will show the warping.
But otherwise it should no longer shrink if washed again.

Hopefully.

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