Pattern writing is based on following a series of logical steps, and involves converting measurements to stitch and row numbers. Many pattern instructions do not include a schematic or drawing of the garment pieces with measurements. In the following example, we are going to use a pattern with no schematic and do the reverse: convert stitch numbers and row numbers to measurements. Converting stitch counts to final measurements is helpful in checking pattern instructions for errors, as well as providing measurements when pinning your pieces in preparation for blocking.
All you need is the gauge and basic math skills. If you prefer visuals, you can choose to create a schematic for your size, after doing the calculations. Note: In this example, I use only one size for the calculations. The process is the same for any size. I also tend to use inches vs centimeters; the choice is yours, but be consistent.
Example: Classic V-neck Cardigan (Size small-finished bust = 35in when buttoned)
- Gauge: 20 stitches and 33 rows = 4 in(10cm) over textured pattern stitch. What we want is the number per inch, 20/4 = 5 stitches per inch and 33/4 = 8.25 rows per inch.
- Back: 89 stitches – Calculation is 89 divided by 5 (number of stitches per inch) = 17.8 inches. In this pattern it is rounded down to 17.5 inches. The back piece measures 17.5 inches wide to the beginning of the armholes. Note: For all pieces count rows, checking the length, making sure you are working approximately the same number of rows per inch as stated in the instructions. For this pattern the back length to the armhole is 13 inches; you should work between 106 to 108 rows to armhole. This is calculated by multiplying 13 x 8.25 (number of rows per inch).
- After Armhole Shaping: 67 stitches are left. 67/5=13.4 or 13.5in. Armhole length is 7.75 in (7.75 x 8.25=63.9 or 64 rows).
- After Shoulder Shaping: Each shoulder has 16 stitches left – 16/5=3.25in. Neckline – centre 35 sts/5=7in.
- Left Front: 49 stitches – 49/5=9.8 (rounded to 9.5in). Length is the same as the back piece. Note: The front and back pieces should have approximately the same number of rows for the lower border, body to armhole, and armhole to shoulder; so they match row for row when seaming. Armhole shaping is the same as for one side of the back. After the armhole and V-neck shaping, there should be the same number of stitches for the shoulder.
- Right Front: same as the left front, but the shaping is reversed. The measurements will be the same.
- Sleeve: 41 stitches at lower edge – 41/5=8.25in. After the increases are completed there are 63 stitches at the armhole edge – 63/5=12.5in. The length of the sleeve is 17.75in to armhole.
- Cap shaping: cap length is 5.5in, and 9 stitches are left at the top of the cap. Row gauge is more important for the cap, as this section fits into the armhole when seaming together. Again, make sure you are obtaining the correct number of rows per inch.
- Most rib borders measure smaller than the body of the garment.
- Measurements are rounded up or down depending on the pattern stitch used. Multiples or pattern repeats have to be included in the calculations.
- The chest circumference of a cardigan is the measurement when buttoned. In the above example, if you add the fronts and the back measurements: 9.5 x 2 + 17.5 = 36.5 inches; not 35in as the border equals 1.5in.
Below is the schematic of the cardigan pieces.
I hope this helps to make you more confident when following pattern instructions with no schematic.