Impossible to always be right
Unless and until someone has a chance to get used to the fundamental feeling of a latex gasket, short of turning red it’s difficult even for them to be sure if what they are feeling is too much tightness or the initial moment of getting used to that feeling. It’s even more impossible for someone to figure they have the right answer over cyber space. So a little time of acclimatization is good to protect the investment in the suit.
There is a logical disconnect here too. If stretching is argued to work, why cut the gasket right off the rip? The stretching should help enough to give it a try just with that.
Once someone has been thru a few dry tops etc it gets easy to figure this out faster and sooner. But it isn’t always so easy to make that decision when these garments are new to the user.
What with thicker gaskets, I’d suggest
stretching only if a gasket is just “mildly” too tight. If it is really tight, one might as well find some sharp scissors, because stretching will take many weeks.
I’m on my fourth
neck gasket…
I just cut right away now. I stretch the gasket out on 5" shell casing and cut about four rings, before I even glue it to the Kokatat. New sharp razor blade, cut smooth.
Neck gaskets last me about a season, easy to replace.
Another option
I was going through 2-3 neck gaskets a season about 6 years ago, and switched to using NRS gaskets. They come in 3 sizes instead of 2, so there’s less trimming. The rubber is also more supple, and they’re easier to install as a result (I do my own gasket replacements). They last about 2 seasons for me now.
Something about my body chemistry eats gaskets, and the NRS gaskets seem to resist it better. No knock on Kokatat – I think they make the best stuff on the market overall. They just buy their gaskets from a different source.
Before you cut!!
I have a football lineman neck, and the gasket WAS strangling me. I went to the suit manufacturer. They said if it was bad enough, they could go so far as to take it back and install a new neck. First, however, they wanted me to take a flower pot that would barely fit into the neck and work its tapered sides down into the neck and leave it there for a few days. It worked great, and eliminated the problems of cutting or sending it back for a new neck installation.
There’s a difference…
…between stretching a seal temporarily and stretching it until it yields, which is what is necessary in order to loosen it. I would have to stretch a seal over something considerably larger than my head in order to get it to yield enough to fit properly. For someone with a neck size that’s close to the seal size, perhaps stretching is worthwhile but if you need to change the size significantly, it’s a huge waste of time and it will damage the seal.
Sure, you can damage a seal when donning and doffing a dry suit, but if it’s done right, you won’t. The biggest killers of neck seals are skin oil and sunscreen, which cause the material to deteriorate over time and lose it’s elasticity. Eventually, it cracks, splits and tears.
That’s true of ANY seal…
…regardless of thickness.
OS Systems makes four sizes…
...of latex neck seals, though they all run a bit small. You can get them in regular or "commercial" grade, with the latter being thicker.
http://www.ossystems.com/repair/seals.html
They're also selling neoprene neck seals in the same sizes, though they are more expensive ($58 vs. $35) and I didn't see any details on the site. They don't appear on the seals page above, but they are an option on the ordering screen. Although the initial cost is higher, they should outlast latex by a wide margin and be cheaper in the long run, if one of the stock sizes fits you properly.
I emailed them about the neoprene seals and if I learn anything useful from them, I'll post it here.
That is simply not true. I stretch
gaskets with forms not much larger than my neck, and smaller than my head.
You keep pretending to knowledge about the effects of stretching that you have never demonstrated. Why not be satisfied that you have done a good job advocating trimming, and quit trying to prove the unprovable, that stretching “never works”?
You really have been totally blockheaded about this issue. I can tell you, that is no way to persuade people.
I never said “stretching never works”…
…and my previous post indicates that there are circumstances where it will, specifically if you don’t need to change the size much. Whether you can get away with a small stretching form and get a seal that fits YOU is irrelevant, as that DOES NOT work for ME. Period.Don’t try to tell me any different, as I’ve tried several different sizes of form and small ones DO NOT WORK for me. Get it? Perhaps it may work for some other people, but IME, if you have to change the size of a latex seal significantly, stretching is a waste of time.
How do you think latex changes size when you over-stretch it? It does so by tearing on a microscopic level. That damages the material and shortens it’s lifespan. If you don’t believe me, look it up yourself; it’s basic materials science.
Trimming the gasket
With all the discussion of point and counterpoint I’m really interested in using this suit when I get it(Tuesday). So trimming the gasket it will be. With that said what is the preferred method of trimming: razor blade or good sharp scissors? I’m sure this will open up a another can of worms.
Great discussion!
“IME, if you…” That’s the problem
right there. You talk to everyone else here as if your experience extends to them, and that what they can reasonably infer from their experience cannot be true.
There is no doubt that trimming works, that the rings on some gaskets mean they are meant to be trimmed, and that subsequently, trimmed gaskets have normal service life.
But my experience, and that reported by others on pnet and elsewhere, is that stretching can permanently affect a gasket so that it will be comfortable, and that such gaskets also have a normal service life afterwards.
Now, I can claim to be open-minded and flexible on this issue, because in this thread and others, I have told people that if a gasket is real tight, they should go ahead and trim, because it will take too long to stretch enough to be comfortable.
But everything you write on this subject has said that gaskets can’t be permanently stretched, or if they can, they won’t last. You have not qualified what you have said by “in my experience” and you have repeatedly talked as if people could not be having the experiences with stretching that they report.
I think you are entirely justified in having the opinion that trimming is the best course of action. There are reasons for saying that. But stretching works. That is my experience, and apparently others have had the same experience.
Occam’s Razor.
Either will work, but…
…the key in both cases is the sharpness of the tool used. When trimming with a blade, I use a plastic bottle in the seal, so the blade won’t be dulled during the cutting process. When using scissors, I use high-quality sewing scissors, as they will cut cleanly. Using dull scissors will be an exercise in frustration and you could end up ruining a seal.
FWIW, one of reasons I prefer to use a blade is that I find the “rubber bands” that I cut off to be quite useful. 
Can I suggest that you practice on the
outermost ring of gasket material before you cut at your target ring? That way you will get the feel for the blade or the scissors before you start your serious work.
one ring at a time and cut between
Cut one ring at a time and cut between the rings using the ring as a guideline. Try on the neck gasket between cuttings and cut only as much as you absolutely need. They always feel looser on the water once you start paddling. You face shouldn’t be red or change your voice when the gasket is on. You can always take off a bit more next trip out.
I prefer good scissors that I reserve for gaskets. don’t use scissors that you cut metal or paper with as they are too dull.
The key to cutting with scissors is to cut so that you don’t cut to the end of the scissor blade to prevent the blunt edge line - this is bad: ----| this is good: --------- If you have ever cut metal or good fabric you will know what I mean. It isn’t rocket science and a mistake or taking off too much is correctable by replacing the gasket so don’t fuss too much!
Suz
Thanks
Suz
For all your guidance and advice I was leaning towards a different suit till I tried on that GFER a couple weeks back at your presentation.
I would be very intersted
to hear what they have for neoprene gaskets. Neoprene can have so many advantages over latex.
Having both, I’m not so sure. List some
advantages if you want to.
There are two major advantages…
…of neoprene seals:
- Durability - Neoprene is much more durable than latex and less affected by sweat, skin oil, sunscreen, etc.
- Eliminates latex allergy issues for people that have them.
That said, they also have to fit properly, since they’re not generally designed for trimming or stretching. That’s why I’ll probably experiment with making my own, since I can custom-fit them.