What is a sock machine cylinder?
The cylinder is the rotating drum of a sock machine that holds the needles. Its diameter and needle count set the sock's width and density.
What the cylinder controls
Socks are knitted as a tube on circular machines. The needles sit in grooves around the cylinder, which turns while cams raise and lower each needle to form stitches. Two numbers describe it: the diameter, measured in inches, and the number of needles.
The diameter sets the circumference of the knitted tube before the sock relaxes and stretches. A larger cylinder suits wider legs and bigger sizes; a smaller one suits children’s socks. The needle count on that cylinder sets how fine the fabric is.
A common adult size
Every machine at the production site we use in Istanbul has a 3 3/4 inch cylinder, a standard diameter for adult socks. Different adult sizes on the same cylinder come from stitch length and yarn tension, then boarding sets the final shape.
For a size range, ask the factory which sizes run on which cylinder, because it affects fit consistency across a crew or quarter program.