Saturday, October 2, 2010

Help!!! A Quilting Query

Can somebody help me figure this out? The math involved is hurting my brain...

I need to make some blocks that are the finished size of a rectangle that is 9" x 8 1/4", and their size before sewing them into the quilt top is 9 1/2" x 8 3/4". Make sense so far???

I would like these blocks to be like windmill blocks made out of 4 triangle-squares, or 8 half square triangles. So what size do I make the four units or the triangles? I realize that these are not squares...but it seems like you should be able to make them anyway from rectangular pieces. I am just a little stumped on the measuring part.

Is there a math wiz out there to help me? I hope this makes sense.

Thanks!

4 comments:

~Michelle~ said...

don't forget the Pythagorean theorem... a^2 + b^2 = c^2... but you don't need that in this case, but sometimes it can be a handy thing to remember

also, i know the rule on half-square triangles is to add 7/8" to the finished size of the square you need, not sure if this would make sense for half-rectangle triangles... but I suppose you can try!

so... you want side a = 5.75" (unfinished, should finish to 4.75") and side b = 5 3/8" (unfinished, should finish to 4.375" within a block)... try a test block w/these measurements to see if that works out.

Judy said...

I had no clue, so I asked the professor. He said to try cutting a rectangle that is 2 7/8 x 10 3/8 then cut through the diagonal to get two triangles.

Julie said...

These look like great suggestions. I'll play around with it and see if I can make them work. I'll report my success... or failure.

Julie Fukuda said...

When I need a pattern for something like this, I draw it out on paper and cut templates from there. It isn't hard to add a quarter inch all around.