Help again... with figuring out the math
 

Hello, it's me again!

Thanks to the wonderful members on this Board, I found tutorials etc on making a granny square block. I only want one block (for a sampler) not a quilt. I made the block in the photo below this afternoon.

[ATTACH=CONFIG]579153[/ATTACH]

I made up a a couple of blocks like this, but one finished way too small (6.5"). The next finished too big! Setting it on point makes it hard for me to do the math....

I need 41 squares and have no idea how big they should be. Sigh.

The block needs to finish at 12.5 inches (will be 12 inches when sewn into quilt). Can someone tell me how to figure this out?

Thanks (I have just purchased EQ7 but I am still working on the beginner tutorials....)

Trish

Trish, if you look at your picture, you will see that there are 4 squares on the diagonal. You want a finished square with a diagonal of 3". I went to my favorite site and it shows the square will be 2 1/8" finished. You will need to cut the squares 2 3/8". Be sure to check for 1/4" accuracy. Hope this is helpful.

http://www.mathopenref.com/squarediagonals.html

Just re-read what I wrote and don't think I made myself clear. You have 4 squares on the diagonal going across and 4 squares down that need to equal 12" finished. 12 divided by 4 = 3, the diagonal measurement.

Another link i like is Bonnie Hunters:
http://quiltville.com/onpointmath.shtml

Thanks so much! I think I can wrap my head around that!

But maybe not.... what about the white squares (which will become triangles when I trim them)?

If the finished size is 2 1/8", shouldn't the cut squares be 2 1/8" + 1/2"= 2 5/8"?

Nice block, Trisher. :thumbup:

Edit: Forgot to mention that you should cut your white squares
same as the rest of the squares just like you did before. Then
trim 1/4" from the points. Check the tutorial I posted earlier.

Maureen, you only added 1/4" for the seam allowances. You need 1/2" (1/4" on each side) so the squares should be cut at 2 5/8".

from Eq7 -

Thanks all... so Dunster... if I use triangles would that involve sewing a y seam? Thanks for your work on my behalf!

One day EQ7 will do that for me :rolleyes:.

No, you don't need any y seams. You assemble the block's diagonal rows with the setting triangles added in with each row, then sew the diagonal rows together. It's the same as with a quilt that's on point.