Latex Gaskets - Trim or stretch??

I tried doing an archive search, but didn’t find what I was looking for to satisfy my concerns.



I have a Semi-Dry suit, with latex Wrist gaskets. As it was, the wrist latex gaskets were so tight, they hurt my wrist, and cut off my hand circulation. I heard of stretching them some, by putting a plastic bottle in them during storage. I also heard of trimming them too.



I tried a 20 oz Pepsi bottle stuck in the wrist gaskets during storage, but that wasn’t enough. I keep 303 on the gaskets, so I am doing that to protect them (as I had read here). After the last time I wore it, I stuffed a 1 Liter soda bottle in the wrist gaskets, but it was hard to get the bottle in the gasket. I am afraid of ripping it while struggling to get the bottle into the wrist latex gasket.



I had also read here that if they are not trimmed “just right” it can cause them to tear at a later date.



So to the Latex gasket experts, which is best? To trim them, or to stretch the gaskets? Am I taking a risk by stretching them as I am to accomodate my large wrists, or should I break down and carefully trim them. If trim is the word, what is the best way to do this?



Thanks to all who replies trying to help!

Trim them
As you’ve learned, latex has an excellent memory and stretching is ineffective. In order to stretch it permanently, you have stretch it to the point that you damage it. That shortens the life of the seals.



You can screw around with stretching for days or weeks, shortening the life of your seals and still end up trimmming them anyway, or you can just trim them and be comfortable immediately. What sounds more sensible to you?

trim

TRIM

Trim!
Insert a beer bottle or similar beverage container into the wrist gasket to hold it firm.

Use a new X-acto knife and a steady hand. Remove a ‘ring’ or 1/8" of material at a time. You can always trim more off if needed.

Carefully trim them

Nick the gasket?
If you do nick the gasket, try a dab of aqua-seal on the nick.

Thanks to all!
Thanks for your help!

I used sharp scizzors on my wrist
gaskets. If you use a razor on the gaskets while stretched over a bottle/can, be careful not to stretch them too much…that’s where the problems can occur with nicks spreading. Stretch them just enough to make them snug on the can/bottle.

don’t cut UNLESS
Jim,

Don’t trim the wrist gaskets unless they are conical and have rings. If you have the Kokatat suit (which is what I suspect), they are not conical and are straight. If they are straight, trimming them will only increase the pressure in one spot.



I too had the same issue with the standard wrist gaskets on the women’s medium. I’m told my wrists are large. I stretched my wrist gaskets to no avail for the whole off season. They are barely tolerable. I have been lazy though and not replaced yet. Finally took the time to order the wrist gaskets and will replace when they come in.





Different brand seals are treated differently. No one answer for all.



Suzanne

Don’t Trim
I’m in the don’t trim camp – I too have large wrists and every wrist seal I’ve tried off the shelf leaves veins popping out. I’ve had good results with stretching 'em – I found some plastic cups in the kitchen cupboard that work great (somewhere between your 20 oz and 1 liter pepsis, but with a nice taper).



And, I figure that manufacturers know what they are talking about – Here’s what Kokatat says:

“Latex gaskets are intended to fit snug – they will stretch a little with use. If they are too tight, stretch them overnight (or longer if necessary) onto some kind of form a couple inches larger than neck or wrists.” http://www.kokatat.com/documents/DrySuitStorage.pdf

And,

“The neck gasket on your Kokatat dry suit is designed to be trimmed (Kokatat wrist gaskets are not designed this way).” http://www.kokatat.com/customer_service_usage.asp



And this from the fine folks at NRS – “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."


Disagree
Trimming wrist gaskets (which I have done on both of my dry garments) does not increase the pressure in one spot. While you are definitely reducing the area of contact with the wrist, you are also greatly reducing the amount of pressure (skinny rubber bands are not as strong as fat ones.)



Since you’re convinced that you have to replace your wrist gaskets anyway, why don’t you try trimming them? I’ve found that reducing the width of contact to about 1/2 to 3/4 inches makes mine MUCH more comfortable.

Dealing with nicks
If you happen to nick the edge of a seal, it’s best to simply trim off a sliver of latex and remove the nick. Seals don’t need to have perfectly even edges to seal properly.

Agreed
I have yet to find a seal that doesn’t respond to trimming, regardless of shape. While rings on the seal make it easier to trim it evenly, they’re not important.

I stretched…
the neck seal of my dry top. It was the recommended method from a sales rep at MEC.



The unstretched seal was tight enough to change my voice and a week wrapped around a large bowl did the trick. I’ve had almost 3 years of fairly heavy use and it’s still going strong.



Ian

And other manufacturers…
…such as Stohlquist and OS Systems - who MAKES latex seals - recommend trimming them. Scuba drysuit makers - who’ve been making drysuits a lot longer than any kayak clothing company - universally recommend trimming.



I know from experience that stretching wrist seals over something 2" larger in circumference than your wrist will do little or nothing. Stretching over something 2" larger in diameter will damage the seal. What are you supposed to do when stretching fails (it WILL fail if you have large wrists)? You either trim the seals or you don’t wear the dry suit.



BTW, here’s the entire text regarding neck seals from Kokatat’s site:



“TRIMMING IS NOT TABOO!

The neck gasket on your Kokatat dry suit is designed to be trimmed (Kokatat wrist gaskets are not designed this way). The neck gasket should fit tightly without being too constricting. If stretching the gasket over a form does not increase the comfort, trim the gasket one ring at a time until it is comfortable but does not allow water in when you are swimming (see gasket trimming instructions). Consult your dealer or Kokatat customer service if you have any questions, and remember, cut once and test before cutting again!”



Obviously, they have no problem with trimming.

wrists are different than neck
As stated previously, Kokatat wrist gaskets are not made to be cut. I was referencing wrist gaskets as that is what the original poster was asking about.



The rings make it easier to trim - agreed. BUT the main difference is that the ones with rings are usually conical. Conical wrist gaskets and conical neck gaskets are made to be trimmed.



Straight gaskets are not.

Actually,
OS Systems recommends that you stretch before you do anything else (and only refers you back to the dealer for re-sizing or trimming):



“New neck or wrist seals may feel tight or a little restrictive at first but will relax with use. It is possible to pre stretch your seals by inserting a soda bottle into the neck and/or wrists while soaking the rubber with liquid silicone. This should make the seals feel more comfortable. Contact your dealer if you still need any additional sizing or trimming.” http://www.ossystems.com/repair/congr.htm#seal



Remember, the original question was regarding Wrist Seals. Kokatat’s info regarding trimming was concerning the neck seal – Kokatat clearly says their wrist gaskets are NOT designed to be trimmed.



Obviously, you and other folks have gotten good results in trimming their wrists. I was merely pointing out that it isn’t the only way, and that in fact the major manufacturers recommend that you stretch the wrists. I have large wrists and have not needed to resort to trimming ‘em. (However, I did follow Kokatat’s recommendations and did trim the neck gasket). And, regarding the comment that stretching shortens the life of the seal – this has not been my experience. I’ve heard that if you get 5 years out of a set of drysuit seals you are doing OK. I finally had to replace the seals on my first drysuit after over 15 years of use, and I just blew out the wrist seals on a semi-dry top after over 7 years of very heavy use.


I could see
where this would be a bigger issue with folks that wear a small or medium sized suit but have bigger than average necks and/or wrists. Don’t overlook the fact that gaskets come in various sizes. One could easily have large sized gaskets installed on smaller suits. This prevents the need to stretch or trim altogether.



Don’t overlook dive shops when looking at gasket replacement- they tend to offer a greater range of gasket sizes and offer heavier-duty gaskets than the paddlesport market.

“Designed” for it or not…
…it’s necessary to trim wrist seals for many, if not not most people. It works just fine, too. Whether the seal is conical or not is basically irrelevent.



As for your seal life, if you’re getting that much time out of seals, it must be due to lack of use, not to whether you trimmed or stretched. There’s no way that seals on a suit that’s used regulary will last that long no matter how you treat them.