This is definitely just an introduction to the subject, but I've been playing around with using a Shetland knitting belt for a while now and get a lot of questions about it. There's a lot of misinformation about this tool and how it's used floating around on the internet, including this rather curious description from the maker of my belts:
"The belt, (in dialect “Maakin’” belt) is used to enable one-handed knitting... Whether doing croft work, carrying the peats home, or cooking; they knitted with one hand - the other free to do something else."
I have seen knitting belts recommended to people who are only able to knit one handed, and don't doubt that it is possible to use the belt to support one needle and manipulate the other needle and yarn with the hand on the opposite side. However, I've never seen any evidence that this is how the belts are usually used! It might be quite helpful as a place to quickly tuck your knitting when you need to attend to a pot boiling over or a crying baby (although I'm not sure I'd want to pick up a baby with a bunch of dpns sticking out from my waist!).
Everyone I've seen using a belt still holds the right needle (and the belt generally goes on the right), but having one end fixed means you can hold it more lightly and swing it back and forth on that pivot.
The leather knitting belt is distinctly Shetland but developed from the earlier use of knitting sheafs which were much more widely used. Kate Davies has an interesting post about these sheafs as objects, with some beautifully crafted examples. In shetland the sheafs — or wisps — were made from a bundle of feather quills with a knotted outer casing. The sheaf would be tucked into the wearer's belt and the needle inserted into the tube.
The leather belt is worn with the pad on the right and the number of holes allows the knitter to find the most comfortable one for that needle length. It also means that different holes can be used for different needle sizes, as Hazel Tindal writes:
"When using bigger needles (eg 4mm) I try to limit the holes used so that I don't stretch too many. The knitting needle shouldn't have room to wiggle about."
I love seeing Hazel's collection of well worn belts, I wish mine were so broken in!
3 or 4 long double pointed needles are used. I prefer 3, and find the really long ones to be a bit too long. I'm currently using these although I did have one bend and then break so the quality isn't wonderful. Much higher quality ones are made by Inox and are available to order from Jamieson and Smith but I do wish there was a 35cm length.
How to use it
The right needle is inserted into a hole in the belt at a level that puts the other end in a comfortable place. It's then held under hand and the yarn can be manipulated with either or both hands. I think video's more useful here!
Apologies for the audio quality, this is actually the second attempt — somehow no combination of recording equipment and location as working well for me today. Huskiness from a horrible cold doesn't help!
Learning (like any new style) mostly requires fussing — with position, needle length and number of needles — and lots of practice. The most difficult part of learning to knit with the belt for me was the realisation that I didn't need to change my knitting style that much — I spent a lot of time trying not to hold the right needle or attempting to keep it stiller than necessary.
Here's how I wrap the yarn on each hand when knitting English and Continental in case it's helpful.