Thread: 8 1/2" Nine Patch Block

Originally Posted by chickadeee55

Hi,

Can anyone tell me what size blocks I would need to make a finished 8 1/2" nine patch block. If possible I will try to use strips, but I can't figure out what the width of the strips need to be to get a finished 8 1/2" block after sewn together.

The closest I came up with was 3 inch strips, three sewn together would give me a finished 8" block, I am not sure that is correct.

3.333333333333333333333333333333333333333" which includes you seams. Why not go to 9"

Originally Posted by mucky

Just do 3.33333333 and sew a scant bigger seam

8.5 divided by 3 equals 2.83333333333333333333333 plus a half inch for two seam allowances makes 3.3333333333333. Which requires a 1/4" seam allowance all around. Any more or less and you won't get near 8.5"

Originally Posted by lfstamper

3 5/16 is what EQ7 says. Make a test one first to be sure.

You can't divide 8.5 by 3 and get any number that is a 16th of anything..5/16 is close to .333333333333 but it's not--it's 3.125

Originally Posted by Holice

If you are making a picnic blanket I am wondering why you need the 8.5" block. It appears to me that you would be easier to alter the large block cut from the fat quarter rather than all those very odd size smaller squares for your 9 patch. For me it would be too much aggrivation to deal with an odd size smaller square and more precision to get it exact. More flexibility in the larger squares and considering all fat quarter are not the same size.

Good point. What I've seen, FQ's are in the neighborhood of 18". Generally a bit less. I'd be tempted to cut 6 7" squares, add a bit of a sash and then make the 9 patch 9". Or even go to 6"

Or cut 3" strips to end up with 7.5 finished and then cut the FQ's to 8".

Formula: finished block size divided by 3 and add 1/2" for seam allowances = 8 1/2" nine patch blocks