The percentage method of creating a sweater pattern uses the chest
measurement plus an allowance for ease of fit as a basis for all other measurements.
The chest measurement is treated as the 100%; all other measurements are some portion
of that measurement. You may prefer (or need) the body or arms of the sweater to be a differnt length than
that which is calculated by this method. It is acceptable to work a few extra rows or a few less rows into the
body or the arm length.
And before you go any further, obssessed in the quest of a free pattern,
be aware that this pattern is a percentage approximation. If you are accustomed to
having a pattern that spells everything out to the letter
or if you are a beginner this pattern may not meet all your needs.
The pattern you will get from this process will be a guideline to making a
sweater, but you need to know something about what you are doing. Or be a bit
adventurous.
Important: Make a test square in the pattern stitch in
which most of your sweater will be done. The test square should be made by
casting on about 25 stitches and working about 25 rows. Ideally the test
square should be 15 x 15 cm. This size allows you to get a good measurement
of the gauge without the interference of the selvage. Knowing your gauge is
critical to the proper fit of any sweater pattern.
The pattern is proportioned for an adult. If you use it for a small child you will need to make the neck larger to
accommodate the proportions of a child's head.
The best feature of this method is that you don't need to change your needle size or yarn to
try to match someone else's gauge. This method makes the pattern fit your gauge.
The pattern is written as if the pattern stitch is stockinette stitch. If you use some other
stitch for your test piece, you will have to mentally substitute the name of your pattern stitch
wherever the pattern say stockinette stitch.
About the type of fit. It is not a sophisticated method. I add a factor to the chest measurement.
The factors are Snug = 5 cm; Comfortable = 10 cm; and Loose = 15 cm.
About the needle size. It can be US or mm sizes. The needle size does not enter into calculation of the garment pattern.
It is used to suggest a smaller needle size for the ribbing.