The yarn on left is an entire skein of the same Premier Home 85% cotton, 15% polyester, size 4 yarn, except, I boiled it, and dried it in the clothes dryer on hot, in order to preshrink it. The entire skein on the right is in its original, unshrunk condition.
I boiled this yarn in the pot for 15 minutes, and let it sit in the hot water for another 30 minutes, after which I squeezed it out, and placed it in the clothes dryer on a hot setting. (Its confining thread came off, resulting in the jumbled yarn that you can see above. I dried it about three more times on hot confining the yarn in a sock, and after this placed it in the sun for two more hours.
It took me an hour in front of the TV to untangle it, and make it into a ball of yarn. I wondered if rolling it into a ball would undo any shrinkage, because of a very slight residual dampness in the yarn.
I wanted to test at least two things:
- Did boiling the yarn make any difference in the crocheted outcome as seen in these coasters?
- How much difference did the crochet hook size have on the coaster size?
To test the shrunk yarn against the pre-shrunk yarn, I made six simple double crochet coasters, three with the preshrunk yarn, and three with the pre-shrunk yarn. For each treatment of yarn I crocheted one coaster, in order of increasing hook size, a G hook, an H hook, and an I hook. Two yarns times three hooks, gives the six coasters.
I measured and weighed the coasters, after which I washed them in hot water, and dried them several times on hot, until they were dry. The coasters ended up looking like this.
The top row of coasters is made with the pre-shrunk yarn, and the bottom row is made with the unshrunk yarn. The first column is made with the G (red) hook, the second column is made with the H (orange) hook, and the third column is made with the I (yellow) hook. It is clear that the hook size made more of a difference in diameter than did preshrinking. (Other observations and figures bore this out.)