Thursday, August 14, 2008

Knitting Math 101

Every once in a while Bert decides to play a rousing game of "Where's Bert?" This week was no different. I decided to organize some of my knitting magazines and bought some holders at Target. Once a few magazines were taken off the shelf of the bookcase Bert saw his chance. Good try Bert but this round has to go to Chief. It took him less than 2 minutes to find Bert. Better luck next time!

Speaking of Bert - today is his birthday. My baby boy is 4 years old today. Bert joined the family on Nov 14th so we'll celebrate that day as well. For his birthday we had stinky cat food (the boys rarely get wet food so its a special treat) and we had lots of little pieces of paper being thrown around the house so he could chase after them. Hey - he's easy to please!

Geometry and Knitting

20 years ago I knit a sweater. Well, actually I knit many sweaters but - the one that's been on my mind lately is a stash sweater. I knit this one from all the leftover balls of a yarn that we had at the shop. There wasn't enough of any color to make anything so I played around. This sweater starts at the neck and works in the round in four sections with the increases in the middle of the front and back and middle of the sleeves. Every other row adds a stitch at the beginning and end of the section and there's random stripes. At one point you stop working in the round and knit the corners of each part - the front, then the back, then the sleeves. This whole thing ends up looking like a cross and is folded in half and the seams are sewn up. (Bloglines/my computer isn't behaving right so I can't get a picture of the old one posted right now).

I had a bunch of leftover yarn so decided to make a new version of this sweater. I gathered all the similar gauge yarn and cast on the neck. The neckline was fine. I started around, added stitches every other row and got about 6 inches into this and wondered how long I needed to knit before I started the corners. You can't measure the width because you're knitting at an angle. As you come around you're actually knitting from the belly button to the shoulder. So I had to figure out how long that distance had to be to know when to quit knitting in the round. CRAP! How did I figure this out 20 years ago. Then I remembered - The Pythagorean Theorem. That would give me the answer.

How the heck did I remember something from high school geometry from over 35 years ago!?! Better yet - what was this theorem? I knew it would give me my answer somehow; but, couldn't remember what it was. The Internet is great. I did a search and got the answer. If you have a right angle triangle- the sum of the square roots of the 2 sides equals the square root of the long side (the hypotenuse). Now, the fact that I remember any of this really impresses me. There's obviously some gray matter in my head still cranking away at old math facts.

There's still a problem. I have to figure out which right angle triangle in the sweater will give me the needed figures to get me the answer to - when do I switch the area I knit on. Better yet - why don't I just measure the old sweater and call it a day! Maybe if I use Elizabeth Zimmermann's percentage's and figure out how long the neck to armhole needs to be then I could use that to figure out when to switch. Maybe if I figure out the rotation of the earth and the lunar schedule I'll know when to switch. Maybe if Michael Phelps wins His next gold it will be time to switch. HELP!!!

My brain hurts - I'll think about this tomorrow.

4 comments:

Guinifer said...

Hah - the girls just won Silver & Gold in the All 'Round in Gymnastics - time to change again!

Wye Sue said...

you wont believe it but it was the boys' birthday as well !!!
They are meant to be old men of 12 but you wouldn't know it ;-)

Miss 376 said...

Knew I should've paid more attention to maths! Hope you work it out

nitzie said...

I was following you until you got to the word "geometry"! Good luck on that. (Has Bert not learned the transporting-into-closed-closets hiding trick?)