I have a block (supposed to be for the yellow and blue swap) that has a lot of seams and so it's not quite measuring up to it's supposed finish size.

For the first time I have drawn a square on the corkboard, wet the block, and pinned it to the square to make it the right size. There was definitely enough movement in the seams to get to the full size, it's not distorted at all and none of the seams look wavy or odd, so I'm really pleased so far.

My question is, what happens when I take the pins out when it's dry. Will it hold to the proper size quite happily, or will it shrink back?

Based on my experience with Mariners compass blocks it stays put quite happily. :D

Mariners compass almost demands blocking. It helps take out the waviness that occurs when peicing wedges into a full circle.

When I block a finished quilt, it stays put until the next time it gets wet. Like a sweater, you block it each time you wash it. For one unfinished block, once it's sewn into a quilt, it shouldn't need the special treatment.

ditto

you could always iron some freezer paper on the back to "hold it" until it's sewn into a quilt.

You ladies are genius! I made my first block for the DJ swap and it came out just a smidge small. I'm going to try this and see if I can get it the right size! I never knew you could do this!

Excellent! This has made my day. I knew you *could* block it to make it right, but I'd never done it.

Sharon Schamber has a Youtube video demonstrating how she "blocks" blocks. She uses spray starch to ensure the block holds its shape until quilted. Here is a link to her first video (I think she has others on blocking too):
http://www.youtube.com/watch?v=i6aplw_tVZc

Thanks. This is such useful information.

Thanks for the link! :-)

I did not know you could shrink a block too.