Originally Posted by
PlanoDebbie
Here's the simple way to resize blocks:
Start with the size you WANT divided by the size you HAVE.
In your example, you WANT a 12" block, but you HAVE an 8" block.
Take 12" (WANT) divided by 8'' (HAVE) and you get 1.5 That would be 150% to increase on a copier.
If you WANT an 8" block, but you HAVE a 12" block, you do the same thing.
Take the 8" WANT and divide by the 12" HAVE to get .6667. On a copier, you would select reduce to 67% to get your new size.
This works only if you are dealing with the *finished* size of the pieces, and then you still need to add the 1/4" seam allowance to each edge. If you do this with the *cut* size of the pieces, the cutting sizes for the new pieces will be off.
Example: Start with a 9-patch that finishes at 6". Each finished patch is 2" square. Each cut patch is 2.5" square.
If you want to enlarge to 12" and simply double all the *cut* sizes (12/6 = 2), this results in cutting patches 5" square. However, if you sew the 5" patches together with 1/4" seams, the resulting finished 9-patch will measure 13.5" (because each 5" patch will finish to 4.5").
If you do the same and double all the *finished* sizes, you get 2*2" = 4"patches. Since this is finished size, you will need to add seam allowances, which means you need to cut patches 4.5". This results in a finished block of 12".
I think......
