I Never Thought I'd Use Algebra in Real Life

While googling to find out how to calculate the size of fabric I would need for the exterior and interior pieces of a handbag with boxed corners 2.5" deep, I came across something that initially made me cringe, but in the end proved to be very useful and dare I say it... fun??!!

A + (B x 2) + C = D
(C/2) + E + F = G

- A = finished width of bag
- B = seam allowance
- C = depth of bag
- D = width of fabric to cut
- E = finished height of bag
- F = bottom seam allowance
- G = height of fabric to cut

C'mon, I know I'm not the only one who just felt their stomach turn at the sight of that algebraic equation and that long list of variables (I think that's what they're called)!! These are the formulas for finding the fabric-to-cut's height and width. I usually just make the bag the size I think it should be, and then box the corners by about 1.5" (I make my own sewing patterns). But this time I wanted to do them a bit deeper and was scared I would mess it up, especially since I only have a limited amount of this certain fabric I am using.

When I first read the instructions, I immediately dismissed the project all together because I thought it would be too hard. But then I went back timidly and tried the formula. A short while of chickenscratch later, and presto! I had the dimensions of the bag and they were close to what I had assumed I would need to cut!

Math is not that bad! I hated math in school. I always passed with the lowest score you could get. I guess I needed the right motivation...sewing! :)

The next time you are going to create a custom bag, give the formula a try! It is kind of fun.

Example of a boxed-corner makeup bag from my store (2010)