Saturday, October 27, 2007

Remember high school geometry?



You know, that class you HAD to take to graduate and you spent hours doing proofs and wondering just WHAT you would EVER use any of this for?

May I present the answer (at long last) to that question!

I have been making a quilt for my daughter and her new husband. The center is a large monogram for their names, and the outside is a traditional double wedding ring.

Now a lot of the new wedding ring quilts I have seen have taken the easy way out, squaring off all of the blocks so there is a nice neat rectangle outside edge which makes calculating the required binding a snap.

I, however, opted for the more traditional edge, and since I had seriously adapted for the monogram block in the center, I was going to have to figure out just how much bias binding I needed (yes, it HAD to be bias binding --- all those curves afterall).

So, I measured one of the "corner" blocks and one of the regular blocks and calculated how many inches of binding I needed to go around the quilt -- rounding up at every turn to make sure I had enough.

And then is when I put that old geometry class to work -- remember the formula for figuring the length of the hypotenuse of a right triangle (you do remember what the hypotenuse is don't you?) ok, A squared plus B squared equals C squared

After measuring the fabric I had to make the binding out of, I knew that I had a right triangle with 42 inch sides when I started which meant the hypotenuse was about 59 inches -- on the FIRST cut, well, several calculations later, I knew that all I needed was that triangle to make my 400 inches of binding.

So, yesterday I did the machine stitching to the back of the edge. Then it took me about 2 hours to roll the edge, miter each inside point where the rings come together and pin it. Today I begin stitching.

Wow, who knew? We actually do use some of that high school math stuff!!

2 comments:

Nancy G said...

I've also used geometry to "size up" my pecan pie recipe. It was originally written to make an 8 inch pie, and I wanted to make it a 9 inch. Enter ye old formula for calculating the volume of a circle, V=(pi)r squared. (I know, pi r round, cornbread r squared...teehee!) It didn't take the depth of the pan into consideration, but it certainly was close enough, for baking or government work.

Laura Lynn said...

LOL Bev!!!! Yep, they really did know that this stuff was useful...who'd have thunk it? :)