By Marian Lewis
If you have been frustrated in the past trying to figure out how much bias you need and how much fabric you need for it, here is a simple formula to help you determine just how much bias you can cut from a square of fabric no matter what width of bias you want.
Keep this handy in your sewing notebook for future reference.
Bias Formula To Determine How Much Bias You Can Cut From A Square Of Fabric
Multiply the length by the width of the fabric square.
Divide this number by the width of bias needed. This will tell you the number of inches of bias that you will get.
To find the number of yards, divide the number of inches by 36 (the number of inches in one yard).
Here is an example of how to do your calculations for a sewing project:
Determine how much bias you need for your project.
Let's assume that you are sewing a set of placemats and you want to sew a half inch binding around them.
This placemat measures 18 inches by 12 inches. (18 + 18 + 12 + 12) = 60 inches around one placement.
Eight placemats (8 x 60) = 480 inches plus a little extra to overlap the ends of the bias on each placemat.
For this example, we will add an extra 2 inches for each placemat or 16 inches. 480 + 16 = 496 inches is the total length of bias that you need for this project.
To get the number of yards of bias that you need, divide 496 by 36 (the number of inches in one yard).
That gives you 13.7 or about 14 yards that you need to bind all 8 placemats.
Determine the width of the binding that you will cut.
You must cut the binding 4 times the finished width.
So, for a one half inch finished binding, you must cut the binding 4 x 1/2 inch or 2 inches wide.
Now you know how many yards of binding you need and how wide you must cut it.
The next question is how many yards of 2 inch wide bias can you cut from a 36 inch square of fabric.
Use the above formula to determine the yardage in a 36 inch square:
36 inches x 36 inches = 1296 inches
1296 inches divided by 2 inches (the desired width of the bias) = 648 inches
648 inches divided by 36 inches = 18 yards
So, if a 36 inch square will give you 18 yards of 2 inch wide bias, you will need an extra yard of fabric to make the half inch bias binding for 8 placemats.
A 45 inch square makes about 28 yards of 2 inch bias (for one half inch finished bias binding).
With this information, you can easily calculate all your bias requirements. No more guessing!
It just makes sense!
©2009 Marian Lewis - All Rights Reserved 1st Step To Sewing Success
Marian Lewis is a sewing instructor and the creator of an amazing new fitting method for hard-to-fit sewing folks. In her ebook, "Common Sense Fitting Method For Hard-To-Fit Sewing Folks Who Want Great Fitting Skirts And Pants", find out step-by-step WHAT you really need, WHERE you really need it and HOW to apply that to a commercial sewing pattern. It just makes sense!