I designed the Argus Hat for an averaged-sized adult head, which is around 22 or 23”/56-58.5cm, and if you are using worsted-weight yarn, you should cast on 96 stitches (or 88 if you like it a bit tighter). But what if you want to use a different weight yarn (fingering, sport, DK, and aran/bulky are all possible), or what if you want to custom-fit the hat to someone with a bigger head (like for my husband who has a 24" noggin) or a child?
If using a yarn weigh other than worsted, you will need to get a nice firm fabric (but not as tight/dense as you'd try to get with socks) with your SMALLER needles. This is the stitch gauge that you will use for the cast on.
If you are using a weight other than worsted, or if you want to custom-fit the hat, use the following table:
(Head circumference - negative ease) = hat circumference.
Hat circumference x stitch gauge = CO number. Adjust up or down to the nearest number divisible by 8.
Minus 4” or 7.6cm
Stitch gauge per
1 inch or centimeter
CO Actual: Adjust up/down to nearest number divisible by 8:
* Note: Negative ease means that the item is smaller around than the item being covered, so that the knitted item must stretch to fit. Things like hat bands, cuffs and waist bands on sweaters, and the tops of socks are typically made with negative ease. Conversely, positive ease means it's bigger around than the body part, and fits loosely. And zero ease means that it fits exactly without being loose, or having to stretch.
Adjusting the HEIGHT of the hat:
As designed, the hat is a slouchy hat. If you want a fitted beanie, not a slouchy hat, OR if you want change the size (a child-sized hat won't need to be as tall as an adult hat), then you'll use the table below.
To fit anyone regardless of size or age, measure from eyebrows over the top of the head to the base of the skull, and divide in half. If fully covering the ears is a priority, then measure from the bottom of one earlobe, over the top of the head, to the base of the other earlobe, and then divide THAT measurement in half. This is the height of a fitted hat from the bottom of the cuff to the top of the crown.
But ... the hat height = cuff+rise+crown decreases. So, in order to make a fitted hat, you need to figure out how tall the crown decrease section is, and subtract that from the total, and that's how tall you make the hat, before starting the decreases.
Figuring out the height of the crown decrease section can be tricky. Basically, you have to figure out exactly how many rounds are in the crown decrease section (counting both decrease rounds AND the rounds between them, as for this hat you decrease every other round). I usually have to work it in a spreadsheet. But, for the Argus Hat, I've done the work for you. :-)
Just plug in your values into the table, and do the math, and it will give you your hat height.
So, to fit the hat height, do one of the measurements described above, and determine your ROW gauge. If you are making an adult hat, knit until the hat is right about 4" (10 cm) tall from the cast on edge and then determine your row gauge. Row gauge in this hat is tricky, because the number of rounds varies due to the short rows. So, take several measurements, and average them.
If you are making a child's hat, determine your row gauge when it's about 3" (7.5 cm) tall from the cast on edge, and if making a baby hat, determine your row gauge when it's about 2" (5 cm) tall.
Number of CO stitches
Divided by number of decreases per decrease round
(because you only decrease until 32 sts remain). This is the number of regular decrease rounds.
Multiply by 2 (because you are only decreasing every OTHER round)
Add one (because there’s an additional k2tog all the way around). This is the number of rounds in crown.
Determine your ROW gauge (per 4”/10cm)
Convert to rounds per 1”/1 cm
Divide number of rounds in crown by row gauge per 1 inch/cm. This is the height of the crown.
Eyebrow-to-base of skull measurement divided in half:
Subtract crown height from measurement above.
Add additional height for slouch (optional).
Knit to this height before starting the crown decreases.
Here's the pattern page on Ravelry. You can purchase it there, or by clicking on this link if you prefer: buy now.