Pi Day Hats x 3 by Lynn Venghaus

Pi Day Hats x 3

January 2015
Worsted (9 wpi) ?
18 stitches = 4 inches
in stockinette
US 7 - 4.5 mm
65 - 210 yards (59 - 192 m)
Adult Medium and Large 21-22" and 23-24"
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These Pi hats - three versions in one pattern - Beanies and Stocking Hats - are designed to keep your head warm and add a bit of geek fun in the process. The beanies are also a great stash buster project!

People who love Math will love these!
The stripes are worked in rows that correspond to the digits in Pi (3.1415…) – the formula for calculating the diameter or circumference of a circle. Using this pattern, beanies can be constructed using the initial three rounds above the ribbing (shown here in yellow) to represent the 3, a contrasting stripe (shown in black) to mark the decimal and then working the number of rows for the first eleven digits that follow the decimal point. Or you can choose the stocking hat section of the pattern for knitting a longer hat like the orange and black one shown with 27 digits after the decimal. Or knit a much longer version with 45 digits after the decimal where the tail can be wrapped about your neck as a scarf. See the red and blue hat pictured.

Needles: size 7 US (4.5 mm) 16” circular and DPNs or 40” circular for magic loop construction.

The shaping is easy with the help of ring markers.– 1 to mark beginning of round. 10 more for decreasing assistance

GAUGE: 18 st = 4” on size 7 with stockinette stitch

TWO SIZES included: Measure the head just above the ears with a cloth tape. Instructions included for 21-22” as well as 23-24” circumference.

SKILLS NEEDED: Knit, purl, 1x1 ribbing, k2tog, adding a new color, working in the round

The hats are created using worsted weight yarn (level 4). I used Cascade 220 Superwash and Rowan 100% wool superwash. You can use any brand worsted weight yarn but I suggest you use two solid colors and make the round for the decimal in black, white or gold. Yarns that have been test-knitted are listed in the full pattern.
The beanies take two colors of 65 yards each. The stocking hat takes two colors of 100 yards each and the longest version takes two colors and 210 yards of each. All three require 7 ft of a contrasting color (black, white or gold) for the decimal stripe. The longest hat also requires a second 7 ft length for the ‘zero’ stripe.

Charts and written instructions are provided for each style along with several illustrations. I’ve also included the amount of yarn you’ll need for long-tail cast on and the contrasting decimal stripe. There’s also instructions on how to work in the round without having a ‘jog’ when changing colors and how to ‘carry’ the yarn to avoid having lots of ends to weave in.

Get started right away and make Pi hats for your nerdy friends: math teachers, engineering types, accountants, cookie and pie bakers, people who enjoy puns, kids who get good grades, the list is endless! Work them up in team colors to create Beaver Pi, Bronco Pi, Seahawk Pi, Viking Pi, Cardinal Pi, Wildcat Pi, Packer Pi, etc.

A friend suggested working the entire decimal stripe with yo, k2tog to create circles. I’m curious to see how that turns out!