It’s happened to all of us—we warp up a gorgeous yarn, so excited to weave a beautiful project for ourself or someone else, only to discover once finished it’s not at all the size we anticipated.
While few people love sampling (don’t we all just want to get right to the weaving?), it is an incredibly helpful tool that can save you a tremendous amount of time, money and heartache. Understanding how your project will change dimensionally from weaving to wet-finished will give you a far better result than just guessing and hoping – or as I call it, Pick and Pray.
Here is a quick lesson in how to calculate your take-up and shrinkage.
I always weave a 10x10” sample because it produces a large enough piece of cloth to give me a good sense of the hand of the fabric, and it makes the math easier! Here I wove plain weave measuring 10x10” under tension.
But after washing and drying it measured 9” wide and 8.5” long.
While there are different approaches to calculating shrinkage, I prefer to think of take-up and shrinkage as the relationshipof what I started with to what I ended with.
Dividing my beginning measurements by my ending measurements will give me aratio that will tell me how long and wide a warp needs to be for me to get the finished measurements I want.
So in this case, my 10” long fabric ended up 8.5” long. Dividing my starting measured length under tension (10”) by my finished length (8.5”) I get1.176 (10”/8.5”), orthe ratio of my beginning measurement to my ending measurement.
Therefore , if I want my finished woven fabric to be 10” long, I multiply my desired length by the ratio I just calculated to get the length I must weave. In this case, 10 inches x 1.176 = 11.76 inches. If I wanted a 15” long fabric, I would weave for 17.64” (15” x 1.176).
Similarly, for the width, dividing the 10” width at reed by the 9” I ended with, I get a ratio of 1.111. So my warped width, to achieve 10” finished, would be 11.11” at the reed (or 10” x 1.111). For a 15” wide fabric, I would warp 16.66” wide.
Not only do you now know how to calculate for take-up and shrinkage, you have become your own weaving yarn calculator!