While watching the assembly of the raffle quilt a couple of meetings ago I overheard some discussion about how to figure out the size of the setting triangles needed to finish a quilt where the blocks are set ‘on point’. If you know how to figure it out, it is a breeze, but if you don’t (or like me, you sort of knew a while back but have forgotten the details) it can truly drive you crazy.
The formula for side setting triangles is:
Multiply the FINISHED size of the block that you want to set by 1.414. Round that number up to the nearest 1/8 of an inch. Add 1 1/4 inches to that measurement. Cut a square that size, then sub cut into four.
For corner setting triangles, you need to DIVIDE the finished size of the block by 1.414. Round up to nearest 1/8 inch. Add 7/8 inch and cut your setting squares to that size. Then cross cut in one direction to yield two half square triangles.
This handy chart has already worked out the measurements for the most common block sizes, but it is useful to know how to do it yourself, in case you have an odd size block.
And if you are a visual person and need pictures on how it all goes together, check out this tutorial.
Dalmeny Quilters 