Trimming a dry latex hood attached to a dry suit?

[schwerve]

Hi all,

I just bought a dry suit from Bob3 - a fellow ScubaBoard denizen - and I had the chance to take it for a spin in a pool last night. I must say that it is one of the best gear purchases I made. There were a couple issues with shipping, but I was dry as a bone during the dive. Well, mostly, anyway.

The hood is an attached latex dry hood. That is, no water (aside from sweat) is supposed to get into the hood. However, water was getting into the hood. The problem was apparently that my mask covered part of the face opening of the hood. Whenever I equalized the mask, air would sneak out of the mask and into the hood. As the hood expanded from the extra air, it would push the mask away from my face, causing water to leak in. Ascents were no fun either, as I would have to vent the hood, which would let water in.

It seems, then, that the best course of action would be to trim the opening so that the mask would sit completely on my face. Ideally, this would also preserve the integrity of the hood's face seal. I'm open to any suggestions or warnings that anyone may have about this. If you can think of any alternatives to trimming, too, I'm all ears. No, I'm not buying a full-face mask. :money:

 

[captndale]

I have never particularly liked laytex hoods for the reasons you site. Also you need some insulation under the hood to keep your head warm when it leaks. My advice would be to take the hood off and use a neoprene hood. If you can't see yourself doing that, trim the face opening to accomodate your mask, add a purge valve to the top of the hood and wear a short neoprene hood or cap underneath.

 

[Ber Rabbit]

My face is so small my Viking hood will not seal, there are two "pouches" near my eyes. The beanie that came with the suit keeps my head warm even when wet. I dove with a couple of people not too long ago who put the mask skirt over the hood edge around their face so I tried that (I had always put my mask skirt under the seal). The mask skirt now seals the hood to my face and I can keep my head dry most of the time. Like you said, the hood fills up with air and I burp it regularly but have to be careful not to burp it so hard that water comes in. I've only done 3 dives with the mask over the edge of the hood so I'm still working the kinks out. I understand there is a vent that can be put in the top of the hood to allow air to escape but have not done any research on that.
Good luck! Keep me posted on what you find out
Ber :lilbunny:

 

[Bob3]

I get the willies when I hear of folks whacking the hoods off their suits.
Having a drysuit while diving with a wet head is sort of like wearing a raincoat during a downpour with the hood down.
Some folks, due to the shape of the face, just don't have any other option though, but at least explore all the options first before taking the scissors to the suit.
The little button valves run $8 + postage for 2oz.
Here's the standard hood trimming directions; just take care there is enough latex left to seal around the tittle Thinsulate Snoopy hat that comes with the suit:

Face seal trimming:
Your face opening will sometimes need to be trimmed as well; the bad habit of
whacking hoods off was no doubt started by someone not knowing about this. Put
your beanie on, pull the hood up & put your mask on.
Have someone draw a line around the mask & across your chin right below your
bottom lip. Make SURE there's enough hood material to seal past the beanie.
Fair the lines in to make a nice rounded upside down pear shape & snip away.
If you absolutely HAVE to whack the hood, just pull it down inside of the suit &
trim to the same length as the neck seal.
Save whatever rubber you trim off, it can make good patching material. A blown
cuff or neck seal can be temporarily patched & hold up 'till your repair parts
arrive.

 

[schwerve]

Would you recommend trimming the face opening first, or trying out a button valve first? If a valve is the better option, how much air does it take to activate it? To install it, is it a simple matter of cutting an opening and gluing the valve in? Thanks.

 

[Bob3]

Go with the face opening trim, it may save you the $8. It seems like the face opening gets smaller & smaller every year.
The little button valves are easy to install, you just punch a 1/4" hole & install like a "button". They require very little pressure to let the air escape.
I have some pics around here someplace.
I did leave out another option; sometimes called the "German Style" where the folks wear a neoprene hood over the latex. Sometimes a thin hat underneath is needed if they have problems with the latex sealing on their ears.
The neoprene hood effectively keeps the hood squashed down pretty much as long as it fits well.
You can get a thin knit head covering from places that sell sandblasting supplies. They're easy enough to trim down to where they won't get in the way.

 

[airsix]

Once you get your hood fitted properly as Bob has indicated you'll probably love it. A properly fitted latex hood will keep you very dry, warm, and comfortable. I also have a small face, and following the Viking fitting instructions I dive with the mask skirt over the top of the latex. This keeps the hood sealed against the forehead and sides of the face very well. Initially I thought there would be sealing problems where the mask-skirt comes off the hood and into contact with the skin, or where the hood seals around the cheek-to-chin transition, but I've never had any problems (I use both conventional mask and FFM depending on conditions).

-Ben M.

 

[Ber Rabbit]

I was really surprised to find I didn't get much mask leakage with the latex under the skirt. I'm going to try the neoprene hood over the latex (a hood from terrapinwetsuits is on its way) and if that doesn't do what I need it to I'll give the button valve a shot and let y'all know how it worked for me, I'm the queen of drysuit problems :biggrin:
Ber :lilbunny:

 

[Bob3]

Here's a pic of the hood vent/button valve: