How to enlarge a neck rubber seal on a drysuit

Already in the store, I knew that I had to do something about the neck rubber seal. When my drysuit arrived, I read the information written by the vendor (Kokatat) regarding how to handle the neck. I then read more on the Internet about it. The two options that I found were:

• Enlarge the neck by cutting of a piece of the rubber.
  • To make this easier, the rubber seal has a lot of rings marked on it. If you make a very even cut, of the right size, you have a larger rubber seal that will be as trustable as the original one, only larger.
• Enlarge the neck rubber seal by forcing it around something larger than your throat for a longer time (like half a day or more).

I did not like the idea of making cuts in my brand new and way to expensive drysuit. Thus, I went for the idea of threading it over something larger than my neck.

Enlarging a drysuit rubber seal by threading it over a bucket

We looked in the kitchen for suitable bowls and pots. The best thing we could find seemed to be a rather hard plastic bucket from the washroom. By turning it upside down and thread the rubber neck over it, the neck would be quite well extended. In the information material was information about how much the neck was allowed to be extended. The bucket exceeded that with only a slight margin. But the bucket was having some edges. So we took a towel and placed it over the bucket, which was then placed upside down. Then we threaded the drysuit rubber neck over the combination of towel and bucket.

Threading the rubber neck over the bucket was a little daunting. It can stretch well, but it had to be pressed quite hard to stretch it far enough to fit over the bucket. It was very good to do this together. With four hands, and spreading the rubber with the hands pulling from inside the neck, the job was done in a way that did not carry any large risk of tearing the rubber seal.

The drysuit material is Gore-Tex and is not expandable. So the way to get the seal over the bucket is to turn the drysuit outside in, and then first thread the top of the neck seal over the bucket. The part of the rubber seal closest to the gore-tex material is thus not threaded over the bucket at all, but it is so much larger than the neck that it does not matter.

Enlarging had to be repeated a number of times

After the first night, the neck still felt way too snug when testing it. So the neck went back over the bucket also the next night. After that, the size of the rubber neck felt ok, but we could not do any kayak paddling for a couple of days. The day before we were planning to get our kayaks out to paddle, I tested the drysuit again, and again it had shrunk back a little. Thus, the rubber neck spent yet another day over the bucket.

After these first three nights, the neck felt comfortable, and I wore the drysuit during a paddle tour of a couple of hours. It did not feel comfortable, but I could breathe and transfer oxygen through the veins, so it was not too tight.

After yet another night over the bucket, and a couple of more paddling sessions, the neck felt very comfortable. I have used it many times since then, and never again had the need to place it over the bucket. It still fits tight enough around the neck, but there is very little pressure. The rubber just fits, it does not press.