Quilter’s FabriCalc Quilting Calculator: How to Change to Fabric Width – Calculating Backing Yardage

Q: I purchased the 8400 quilter’s fabricalc, and I don’t understand how to change to fabric width for my project. I want to figure the backing using 108″ width material. My project is 113.50″w x 134.25″ long. Thank you.

A: If you only needs to know the backing yardage using 108 Inch fabric, enter 108 [Inch] [Conv] [-] then continue entering 113.5 [Inch] [Top Width] 134.25 [Inch] [Top Length]. Now press [Quilt Ydg] twice. You need to remember that I have it adding 4 extra inches to all four sides for the longarm.

If you have the very first version you will get an answer of 4-1/2 yards which is a pieced back.

If you are using the current version she will get an answer of 8 yards based on linear yardage not pieced.

If you want to piece your back, then add the 4 extra inches to each side (113.5″ + 8″=121.5″ and 134.25″ + 8″ = 142.25″) and multiply length x width 142.25 [Inch] [x] 121.5 [Inch] [=] 17283.38 square inches and convert to yards based on 108 inches by pressing [Conv] [Ydg] [Ydg] 4-1/2 yards.

If you need to figure binding, then change the fabric width back to 40 [Inch] [Conv] [-] before continuing or everything will be based on 108 inch fabric.