Neck gasket adjustments

I just purchased a new drysuit,an NRS Inversion and of course the neck gasket is too tight.

I had always heard it was better to trim the gasket instead of stetching it as excess stretching could crack or weaken it.I trimmed a couple of rings on my old suit’s gasket with no problems but NRS recommends stretching as the preferred method.

Their instructions are:

"New drysuit gaskets may not be comfortable initially but will stretch over time. We recommend stretching new gaskets around something slightly larger than the gasket opening overnight. Trimming the gaskets is not recommended and may cause gasket failure. If a gasket is trimmed, that gasket will no longer be covered under the garment’s warranty. "

The gasket does have guide rings for trimming so I’m wondering why NRS prefers the stretch method.

Any ideas?



Trim It…

– Last Updated: Nov-04-07 4:14 AM EST –

a ring at a time until snug but tolerable. If do the stretch method, half the winter will be gone before you can wear the drysuit without being choked out. If have a "pencil neck", then stretching over a day or two may do it.

The method that provides the route to the most immediate use -- should cut through the endless debate about "cutting vs stretching."


Don’t Know Why NRS Prefers That

– Last Updated: Nov-04-07 6:34 AM EST –

but my dry jacket would be worthless to me if I hadn't trimmed it a couple of times. It's still a little too snug. I might trim it again.

I would guess that NRS had too many warranty claims from folks who trimmed too much.

Notch sensitivity
Here is an experiment that you can do at home:

Take a plastic grocery bag. Find a factory edge at the top, and try to tear the bag. The plastic will stretch a considerable amount before the bag tears, and the tear will be jagged.

Now, cut just a tiny slit in the edge of a second bag and try to tear at the slit. The bag will tear very easily, and the edges of the tear will be much cleaner.

This is called “notch sensitivity”, and it applies to rubber neck gaskets the same as grocery bags.

If you trim, and leave even a small notch in the trimmed edge, there is a very good chance that the gasket will tear.

If you have a steady hand, and can leave a good clean edge all the way around then this is much less likely.

The point is, if you are going to trim, you need to take you time, be careful, and make sure that you don’t leave a notch at the start/end of the cut.

I have had no results
stretching latex gaskets and found that trimming them works great. I suppose that NRS doesn’t suggest trimming because it has to be done very carefully so that there are no cuts left on the edge of the gasket that could start a rip. I have had good results by placing an empty 2 liter plastic soda container inside the gasket and carefully cut around the circumference of the gasket with a razor blade in one continuous cut.

Yes,I can see them having customers butchering a neck gasket and screaming warranty so that explains their reluctance to recommend trimming so I’ll remove one ring and see what happens.

I can’t imagine sending it back for gasket replacement anyway. Much quicker and easier to just install a new one if I screw it up.



in my experience
blood flow to your head will be cut off

long before the gasket begins to stretch

Have a carpenter trim your neck…
…on a lathe.

S’what I did.

Cutting Gaskets

– Last Updated: Nov-04-07 11:16 PM EST –

I've cut my last two neck gaskets. I stretched them for more than 72 hours, and it didn't make a bit of difference. I wore them with their original tightness day after day, and it made no difference. Cutting them extremely carefully is the only thing I've been able to do to make them tolerable. If I don't, it feels like my head is going to explode. But it doesn't take much at all to notch it, and screw it up.

Traffic cone
I’ll stretch it over a traffic cone and with a fresh sharp blade I’ll carefully circumsize the neck gasket one ring at a time.

do it right
I took my suit to a scuba shop. Or a seamstress who can really use good shears.

neck gasket
stretching doesn’t work, cutting ramps up risk for tears but cutting works. my next drysuit will be s Stohlquist B-POD for exactly this reason. Send yours back to NRS!

You really have to screw up badly…

– Last Updated: Nov-06-07 6:19 AM EST – make a notch in a seal when you're trimming it. In fact, I don't see how you could make a notch in a seal unless you intentionally tried to. If you use a SHARP blade or SHARP scissors, trimming a seal is easy and it's pretty hard to screw up. I've trimmed a lot of seals and have never put a notch in one.

Cutting does NOT increase tear risk…
…and returning a dry suit because the neck seal is too tight is just plain silly. Latex seals are meant to be trimmed to fit the user. It’s amazing to me that kayakers are so paranoid about this when trimming is standard practice among divers, for whom reliable seals are literally a life and death matter.

Hi Brian
I’ve always trimmed my neck gaskets–just did a Kokatat drytop a few weeks ago and used it rolling this weekend. I’ve had to replace neck gaskets that tore at a nick site. Once on a long trip in exposed conditions I ended up with a gasket repaired with duct tape. I have never had a wrist gasket tear but then I never had to trim one either. I think that you’re correct, we obsess to much about these things, making the perfect the enemy of the merely good enough. The key point is that stretching doesn’t work and trimming does. OTOH, seems to me that if the BPOD works as advertised, i.e. more comfortable and tear free, then it just may be a better technology for kayaking anyway. Always appreciate your posts, and love your book on carving GPs. John

I love it !! I’m a long-time successful
gasket stretcher, but I’m the first to admit that gasket trimming is fast, effective, and almost always without down-the-road consequences.

The suburban myth about stretching causing damage can be seen as suspect if you consider what uneven, marked stress you put on a neck gasket when you put it on or take it off. That these stresses are transient does not mean they are inconsequential. They are surely the major reason that gaskets eventually fail.

As for stretching, the quoted NRS approach is too mild and will not achieve much. You need a stretching form that is just a little larger than your neck. I use a 3 liter plastic soda bottle. The gasket pulls over it easily, without any of the unavoidable violence needed to get it over your head. The gasket may need to be left to stretch for over a month to achieve the desired level of relief.

I have never had a premature gasket failure after stretching. My gaskets have always held up at least several years.

That’s cool g2d
I’ve used a gallon pretzel jug, but only for a couple of days. Maybe longer would work. In medicine, we’d say at this point, OK, lots of opinions means no clear winner, time for a randomized controlled trial .

Don’t sweat it
Latex gaskets will be obsolete in a couple years and you’ll never have to worry about them again.

I did it anyway
I removed two rings and it fits perfectly now,still fairly snug but my face doesn’t turn red anymore.

Brian N is right,we probably get way too worried about a simple mod to simple part.


latex to be replaced by what?
they are used by every manufacturer on every kind of dry suit, do you know an inside secret as to a miracle material that will soon be found on all these dry suits?