How the rib in a sock leg is knitted
Short answer: The shaft is knitted in rib with an inlaid elastic thread. The rib gives folds that can stretch, and the thread gives the force that pulls the sock back toward the leg. Together the two parts let the shaft give and still hold on.
Rib is folded fabric
A rib stands like small hills and valleys. When the leg is thicker than the sock, the folds straighten out instead of pulling on the yarn. That is why the shaft can stretch without turning thin. When the foot is pulled out of the sock, the folds go back into place.
The elastic thread does the work
Without an inlaid thread, the rib would be flexible but would not hold on. The thread is laid in every row or every second row and pulls the folds together again. It is what keeps the sock up. Over time the thread tires, and the shaft loses its grip. See all bamboo socks for men.
Why the shaft should not squeeze hard
A shaft that squeezes leaves a mark and can feel unpleasant. The aim is an even grip across the whole shaft, not a tight ring at the top. If you have a medical reason for support stockings, talk to your doctor about what suits you. See bamboo compression stockings.
A wide cuff or a narrow one
A wide cuff spreads pressure over several centimetres, so it feels lighter. A narrow cuff concentrates pressure in a thin line and can leave a mark. That is why many prefer a wide rib at the top. It also depends on the shape of the leg and how high the shaft reaches.
When the shaft slides down
If a sock slides down, it is usually because the elastic thread is tired or the shaft is too short for the calf. It has nothing to do with your legs being too thick. Try another size or a taller sock, and wash at a low temperature to spare the thread.
Shaft length and calf muscle
The calf muscle is the widest point of the lower leg, and a shaft that is too short does not hold there. A longer shaft covers the whole calf and spreads the grip over a larger area. If you are unsure, try the sock and walk around. If it slides, the shaft is too short or the sock too big.
How to see the thread
Turn the sock inside out and stretch the shaft, and the elastic thread shows as a thin line along the rib. A strong thread holds the sock better. A thin one lets the shaft give more and presses less. Neither is wrong, they just suit different needs.
Support stockings are something else
A support stocking is built to give deliberate pressure, while an ordinary sock should only sit calmly. The shaft of an ordinary sock should therefore not feel like a support stocking. If you have special needs for support, ask your doctor, then choose a sock made for the purpose.
Caring for the shaft
Wash socks at a low temperature and avoid fabric softener, which can leave a film on the yarn and weaken the elastic thread. Do not pull hard on the shaft when you take the socks off. Let them dry calmly and rotate between pairs, so the thread has time to recover. See bamboo socks for men.
Frequently asked questions
Why do some socks slide down
Because the elastic thread is tired or the shaft is too short for the calf muscle. Try another size or a longer sock, and spare the thread by washing at a low temperature.
Can you see the elastic thread
Turn the sock inside out and stretch the shaft, and it shows as a thin line along the rib. It usually runs in every row or every second row and pulls the folds together.
Is a wide cuff better than a narrow one
Most often yes. A wide cuff spreads pressure over several centimetres, so it feels lighter and leaves fewer marks. The right width does depend on leg shape and shaft height.
You can find the full range at Bamboo-Clothing.com.
