How to Know What Size You Want
I often get asked questions about perm rods and what sizes are appropriate for different lengths of hair. People often want to have really simple “Tab A/Slot B” answers to their questions, when unfortunately this isn’t always possible.
“Choosing Perm rods” is one of those subjects that requires a little “finesse” when it comes to choosing the right one. The size of the perm rod you need to use depends largely on the length of the hair being permed and the amount of curl you want to have in the finished style.
Curl vs. Wave vs. Body
We’ve all heard the terms “Body Wave” and “Body Perm” and “Curly Perm”, and in fact, a lot of the time the use of such terms is confusing. Most people don’t understand what is meant by these terms and how the use of certain perm rods factors in creating these effects. The principle is simple: the more times the hair is wound around the perm rod, the more bends are created in the hair.
The longer the hair is the more times it will need to wrap around a rod of a given size. In order to create a wave that looks natural and balanced to the hair’s texture and length, we generally use larger rods on longer hair lengths. This depends on the desired outcome.
Say we have a client who has neck-length, layered hair and she wants a lot of volume and curl in the hair. Her hair is an average of 5 inches long in its shortest areas. Depending on how tight a curl was desired we’d probably use a gray or white perm rod to wrap the hair. If she wanted less curl and just “body” we’d probably use a purple rod to create the largest and softest wave pattern.
With shorter lengths, using large rods can give large, soft curls and add wave instead of curl. The shorter the hair is, the smaller the range of rod diameters that we would be likely to use would be.
The Rods Themselves
Perm rods are designed on a universal standard. The various sizes are color-coded, even though the manufacturers may use shades of the same color that vary from other manufacturer’s rods of equivalent size. The key is to learn what basic colors mean, since some of the rods may not be readily visible as being different in size.
It should also be noted that perm rods come in both concave and “straight” versions. The concave rods get slightly thinner toward the center and flare at the ends. This has two benefits. One, it allows the rod to sit snugly against the scalp with hair wound around it – to a point at least. And two, it gives a slight variance in the curl making it looser to the outside of the segment for a more natural look. The straight rods have the benefit of creating a uniformly shaped curl.