Sometimes it can be tricky deciding when to start decreases on a hat. I know some patterns tell you to work some such number of inches and then begin decreases or so many repeats then begin, but sometimes they just don’t fit well. I am going to show you what I do to custom size my hats in order to get the perfect fit no matter what pattern you are working. Depending on stitch pattern you may have to do a bit of tweaking, but it still can be done.
First of all the pattern; check your row gauge, then look at how many rows are given for decreasing. You will need to do a tiny bit of math, but I promise it is not too hard and a calculator makes it even easier. First check if your row gauge is given in 1in(2.5cm) or 4in(10cm) increments, you will want to work with 1in(2.5cm) so if given 4in(10cm) simply divide by 4 to get your needed number. Write this number down, else it will disappear! Now if you look at the decrease rows and there are 18 of them and your row gauge is given as 24 rows per 4in(10cm), you would then take 24/4=6 to figure out that you are getting 6 rows to each inch. Then take your number of decrease rows, 18 in this example, and divide that by 6 to find how many inches the decrease rows are: 18/6=3, your decrease section will take place over 3 inches (7.5cm) (just convert this number to centimeters if you are used to working in metric). Now you know that you can knit away on your hat until you are 3in (7.5cm) from your desired height.
Now for the knitting, knit your hat til you feel like it is getting close to size. For me, this starts not too long after I start knitting.. Not because I am fast, but because I like to start trying it on as soon as I have any progress going at all! I like to feel the knitting in place (where it will be worn) as I am working on it, maybe it is an incentive to keep going.. or some crazy thing I do, no idea. I do this with sleeves too, by the way.. All I have done are the ribbed cuffs, and on my wrists they go! Ahem! Back to hats..
You will want to put your hat on your head and pull it down to where you plan to wear it, and then feel how much space is still open at the top. To feel how much space is left place your hands up on top of your head and center your fingers over the opening. To center simply touch your fingertips together and let you hands rest on the hat. You will be able to tell if you are centered by where the hat edge (where your cord or DPNs are at) is under your hands, just make sure it is feeling the same on both sides.
Using a ruler, measure your fingers from where you felt the hat under your fingers/hand to the very tip of your finger. This tells you how far away from the finish you are.
Use the formulas above to figure out how many more rows to knit before decreasing or if you are ready to start now.
The hat shown in the pictures above is my ZigZag pattern. I will use it in the example below:
Gauge for ZigZag is given as: Gauge: 19 sts & 28 rows in 4x4in square (10cm square) stocking stitch; 21 sts & 35 rows in 4x4in ZigZag pattern
I can use either gauge to determine the decrease size; for this example I will use the 28rows/4in gauge given. Also, note in ZigZag you are given options for where to start your decreases to remain in pattern, by using this 3 step process you would be able to easily determine which one works best for you.
As you can see on my card I found, after doing the steps, that this hat only has around 1.29 inches in the decrease row. Knowing this, with the measurement I get above of 2.5in I know I still need to knit a few more rows before starting my decreases. Actually, having this number in mind I can determine that I need to knit around 7 more rows before decreasing. (7 rows per inch, and I am about two and a half inches away from my desired height, the decreases will use up about half of that.)
For this example, I am using my Friendship Hat. The gauge given is 5 stitches and 6 rows = 1 inch in Stockinette Stitch. By looking in the decrease section of the pattern I find that it has 21 rows for the decreases. So filling in my chart I find..
For this example I get around 3.5 inches for the decrease section.
Also note that I did not have to do any math in the first step because the Row Gauge is already given per 1 inch measurements.
If you are knitting a slouchy hat then you can check this by pulling it down lower than you would normally wear it, up to an inch or so more depending how slouchy you want it to look and the pattern. Be sure to read the pattern completely before starting and it should tell you the needed information for determining when to start your decreases. Don’t be afraid to experiment and customize either!