I'm not a prewasher so I can't comment on shrinkage.
I've enclosed a couple of pictures to show you the threads I'm talking about. The bed of my sewing machine is from sewing 2.5 inch squares for about an hour today. It's all over the bed and extension table. The squares were starched before cutting.
It's messy, but to me, the fabric is still worth it.
my ironing board cover
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sewing machine bed
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fabric squares
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