Semi Dry? (advice for a beginner)

[Stu1969]

Hello All.

Before going any further I need to say I go in the sea a few times a year when on holiday so I am not experienced buying any type of gear, I don't know which are good brands, bad brands, what to look for etc.

I would like to ask for advice regarding suits for summer use in the UK. I am pretty nesh, and “think” I enquire a semi dry suit. I have a wet suit with detachable arms which I think is made for kayaking etc, this is just about ok for 20 minutes but water gets it round the neck/zip straight away.
Is a semi dry the way to go? And can anybody recommend a value suit for occasional use?

I look forward to any replies


Regards

Stu

[Ron MacRae]

Stu,
Am I right in thinking you are not going to be diving, just swimming or some other surface activity?

For diving, to any great depth where it is colder, you really need a dry suit.

For messing about on the surface a semi-dry would be fine.
The only difference between a semi-dry and a wetsuit is tighter cuffs and hood so that when the water gets inside, which it will, it stays in and warms up, In the case of a wet suit the water is flushing in and out and so is always cold.

Can't comment on specific good/bad suits as I use a dry suit.

Ron.

[paul_c]

ahh in befor the horeds jump in and say buy a drysuit

i dive in a full wetsuit. and have been doing 70 minute dives in it quite happily. and in winter i do 40 minutes

a semi dry suit is a bit of marketing,

what it actualy is is a wetsuit with tighter wrist, neck and ankel seals which stops the water in the suit from flushing out so it remains warm next to your skin. instead of beeing continualy beingw ashed away and replaced by cold stuff


may i ask if you wear a hood and gloves?

as to brands. personaly i havent got a clue. i am in the midst of trying to finds a suit maker to make me a 4mm semidry witha few of my own specifications rather than off the peg.

bugger to slow.

to counter rons you need a drysuit argument.

at 50m on a long deco dive yes even i would look to a drysuit. but for no stop, 20m max dives which is what i suspect youa re looking at for a maxinum a semi dry is perfectly acceptable es[ecialy in the summer.

[Stu1969]

Stu,
Am I right in thinking you are not going to be diving, just swimming or some other surface activity?

For diving, to any great depth where it is colder, you really need a dry suit.

For messing about on the surface a semi-dry would be fine.
The only difference between a semi-dry and a wetsuit is tighter cuffs and hood so that when the water gets inside, which it will, it stays in and warms up, In the case of a wet suit the water is flushing in and out and so is always cold.

Can't comment on specific good/bad suits as I use a dry suit.

Ron.


Hi mate,

No I don't dive, just mooch around the shore/ rocks and only on holiday with family.

[Stu1969]

ahh in befor the horeds jump in and say buy a drysuit

i dive in a full wetsuit. and have been doing 70 minute dives in it quite happily. and in winter i do 40 minutes

a semi dry suit is a bit of marketing,

what it actualy is is a wetsuit with tighter wrist, neck and ankel seals which stops the water in the suit from flushing out so it remains warm next to your skin. instead of beeing continualy beingw ashed away and replaced by cold stuff


may i ask if you wear a hood and gloves?

as to brands. personaly i havent got a clue. i am in the midst of trying to finds a suit maker to make me a 4mm semidry witha few of my own specifications rather than off the peg.

bugger to slow.

to counter rons you need a drysuit argument.

at 50m on a long deco dive yes even i would look to a drysuit. but for no stop, 20m max dives which is what i suspect youa re looking at for a maxinum a semi dry is perfectly acceptable es[ecialy in the summer.


Thanks for your advice, I know that I defiantly don't want a dry suit. I do have a hood but it does not prevent water entering via the zip/neck area and I don't have gloves and I think I would prefer not to I think.

Stu

[Ron MacRae]

ahh in befor the horeds jump in and say buy a drysuit

Nop. Beat you by 3 mins.:)

Ron.

[Eddie Clamp]

Hi mate,

No I don't dive, just mooch around the shore/ rocks and only on holiday with family.

Then I expect you do not wish to go to too much expense.

I snorkelled off Selsey the other day in a 5 mil shortie that I bought on the internet off the peg for a good price. :) Also bought a 5 mil semi dry in the same manner.

HTH

[Ron MacRae]

Thanks for your advice, I know that I defiantly don't want a dry suit. I do have a hood but it does not prevent water entering via the zip/neck area and I don't have gloves and I think I would prefer not to I think.

If you're not under the water much you don't need a hood.
If you are then it might be a good idea to prevent heat loss.
I think a seperate hood is better anyway as it's less restricting.

A semi-dry will not prevent water getting in.
It will only keep it there long enough to warm up.
It is only a wet suit with better cuffs & neck seal.

There are some excellent thin gloves that keep the dexterity at the expense of warmth. Depends how cold your hands are getting.

Depending on how cold you get will determine what thickness of suit and how many layers you go for, i.e. a one piece or jacket and trousers. The jacket and trousers normally both cover the main torso for extra warmth.

Being a larger person with plenty of bioprene I don't feel the cold too much.
As they say your mileage may vary.

Ron.

[Drew MacIver]

Hello All.

Before going any further I need to say I go in the sea a few times a year when on holiday so I am not experienced buying any type of gear, I don't know which are good brands, bad brands, what to look for etc.

I would like to ask for advice regarding suits for summer use in the UK. I am pretty nesh, and “think” I enquire a semi dry suit. I have a wet suit with detachable arms which I think is made for kayaking etc, this is just about ok for 20 minutes but water gets it round the neck/zip straight away.
Is a semi dry the way to go? And can anybody recommend a value suit for occasional use?

I look forward to any replies


Regards

Stu

I snorkel 9 months of the year in a 5mm 1 piece semi-dry, definatly the way to go imho, for the other 3, i use a 2 peice 7mm semi dry, never had any issues with either, and i go in the north sea (lol).

As for makes, from personal experience i recommend Beaver (makes my winter suit and the wifes summer and winter suits, check http://www.beaversports.co.uk to find stockists local) or Otter ( my summer suit, check http://www.drysuits.co.uk/Wetsuit%20Systems.htm), both available in most good dive shops.

hope this helps,

Drew.


Ps, Paul C, Beaver also do custom made suits quite reasonably priced as well, the wife's summer suit is a custom.

[DRW]

I snorkel in the North Sea off the North East coast of England wearing an inexpensive 1950s-style dry suit that can be worn with undergarments of varying densities to match seasonal changes. The thin covering not only keeps me warm and dry most of the year round but also enables me to swim freely without binding my limbs. I am not encouraging you to follow my lead, just letting you know that snorkelling is a pastime that can be enjoyed with many different kinds of equipment and doesn't necessitate a large financial outlay. However, selecting a suit for snorkelling purposes can be every bit of a personal odyssey as purchasing fins can be. Nobody's response to cold water temperatures is the same. A suit may be too hot for one person, yet provide too little warmth for another. You can't expect to get the best exposure suit for your requirements the first time round. Experience will be a great teacher.

[Toblerone]

You've had some great advice on this thread. I'm particularly intrigued by DRW's '50s style' drysuit (presumably 2 piece 'totes' type) but I fear that type wouldn't last long up here in Orkney as we tend to bump into barnacle covered reefs and barrier blocks a lot. What I use is a 2 piece custom made italian 7mm spearfishing suit, lined on the outside with an unlined inner which means you have to lube it to put it on (ooh err missus!). It is a steal at £220 though (spearo.co.uk do them). It's OK right through the winter if you keep moving around and a joy to swim and duck dive in. Unfortunately we do tend to float in one place attempting to photograph fish and inverts etc. so I have ordered yet another drysuit - a 7mm diagonal front zip jobby from Scapa Scuba. Drysuits aren't really very practical to duck or freedive in due to physics, but you can do it.

[Ding]

If you dont want to spend cash on a drysuit IMHO a good fitting wetsuit is what you want. Good fitting is main point, water wont go in and out of a good fitting wetsuit.

[ChristianG]

water wont go in and out of a good fitting wetsuit.
Are you absolutely certain of that? Really? :D

[Ding]

A good fitting suit should touch you all over like a second skin. If it doesn't it wont work.

[Toblerone]

A good fitting suit should touch you all over like a second skin. If it doesn't it wont work.

Seconded. An open cell inner spearfishing/apnea suit doesn't let water move around at all after a small initial ingress up your back.

[ChristianG]

Seconded. An open cell inner spearfishing/apnea suit doesn't let water move around at all after a small initial ingress up your back.
That latter is the entire point.

A wetsuit, is a wetsuit, is a wetsuit. A semidry falls into the same category.

[Spirit_of_Guernsey]

A proper semi-dry lets in no water whatsoever, the seals are the same as used in a dry suit. The difference is that it does not have an inflater or dump valve and relies on its own insulation to keep you warm rather than a fleecy undersuit.

Unfortunately, a lot of wetsuit manufacturers have called their best wetsuits 'Semi-dry' when they are nothing but a wetsuit with a high peg price.

There is a lot of BS around on the British websites about semi-dries as some people cannot understand how they work, but they do work, and work well. I have done more that 50 dives with my Waterproof Taurus without water entering, including the middle of winter. The downside is that a proper semi-dry is getting into the drysuit price bracket.

[Toblerone]

A proper semi-dry lets in no water whatsoever, the seals are the same as used in a dry suit. The difference is that it does not have an inflater or dump valve and relies on its own insulation to keep you warm rather than a fleecy undersuit.

If it doesn't let in water, how do you get on with squeeze at depth? Presumably people dive semi-drys to the same depths as people dive drysuits to in somewhat warmer climes. I've experienced suit squeeze freediving in a drysuit at comparatively shallow depths. I imagine that could be unkind to those of us with Y chromosomes and external plumbing at greater depths. :confused:

[MattS]

A proper semi-dry lets in no water whatsoever, the seals are the same as used in a dry suit.The materials used to make a drysuit are water impermeable. The materials used for wetsuits and semi-dry suits are water permeable. So yes, you will still get wet in a semi-dry however waterproof the seals are, it is just a matter of time.

The difference is that it does not have an inflater or dump valve and relies on its own insulation to keep you warm rather than a fleecy undersuit.You don't need a fleecy under suit under all drysuits. A 7mm Neoprene dry-suit, for instance, has more than enough insulation for most people to comfortably dive, otherwise starkers, at this time of year. A drysuit is impermeable to gas and water though. The inflate and dump are needed to allow the pressure inside the suit to be equalised with the surrounding water. Wet suits and semi-dry are gas and water permeable, equalising 'automatically' by water penetrating the material, compressing any gas still remaining, until there is no gas remaining.

There is a lot of BS around on the British websites about semi-dries as some people cannot understand how they work, but they do work, and work well.You might want to be more careful with the BS accusations. A drysuit is water impermeable, a wet or semi is not. That IS the difference.

Wets 'work' due to water being a better insulator than air. Water retains heat better than air but it takes more energy to heat up the water in the first place. Semi's 'work' by preventing the energy that was needed to warm the water being 'flushed' away - I.e. A semi is more 'efficient' than a wet. The number of degrees C the water needs to be raised (calories) to prevent the body losing heat faster than it can comfortably replenish it, roughly determines the effective limits between wets, semis and drys. I.e. When heating the water consumes so much energy that it causes body core chilling (hypothermia) within the duration of the dive. These limits are not cut and dry (ha), as the duration of the dive can be adjusted to an extent.

I have done more that 50 dives with my Waterproof Taurus without water entering, including the middle of winter. The downside is that a proper semi-dry is getting into the drysuit price bracket.Permeability is the measure of how fast a material, say water, penetrates another material, say a diving suit. A thick semi with low water permeability may completely resist water penetrating the material within the time it takes to carry out a dive. That is quite different from the water impermeability of dry suit materials, which will prevent water ever penetrating the material within the useful lifetime. Note the penetration times for wet and semi materials are under a few hours at best, while for dry suit materials it is years at worse.

As anyone that has worked with materials exposed to water will tell you, 'Waterproof' is rarely a meaningful measure of anything much and virtually useless within diving. The difference in time and depth between being allowed to describe something as 'Waterproof' as opposed to 'Water-resistant' is not that great.

Dry suit materials are water impermeable. Wet suits and Semis are water permeable. That is, quite simply, the difference between them.

[Toblerone]

Dry suit materials are water impermeable. Wet suits and Semis are water permeable. That is, quite simply, the difference between them.

I must admit this is confusing me. Surely neoprene is impermeable - period. It's the care taken sealing the seams, providing seals and a dry zip etc. that makes the neoprene drysuit dry? A semi dry, if fitted with seals and a dryzip would have to have some of the seams deliberately left unsealed or some other mechanism for water ingress rather than relying on the permeability(?) of neoprene or you'd end up with squeeze at depth. I confess I'm baffled now.

[ChristianG]

I must admit this is confusing me. Surely neoprene is impermeable - period. It's the care taken sealing the seams, providing seals and a dry zip etc. that makes the neoprene drysuit dry? A semi dry, if fitted with seals and a dryzip would have to have some of the seams deliberately left unsealed or some other mechanism for water ingress rather than relying on the permeability(?) of neoprene or you'd end up with squeeze at depth. I confess I'm baffled now.
Well, you've never had to hang a neoprene drysuit up to dry? Takes an awful long time, especially when compared to a trilam suit.

I have a trilam suit. I generally stick myself, in the trilam, under the shower on the beach when back on land, then take it off. Usually the suit is dry by the time I get home (minutes away but there's probably a cup of coffee etc that takes some time). A neoprene suit similarly? Forget it.

[MattS]

Surely neoprene is impermeable - period.Well there is Neoprene and there is foam rubber and there are Neoprene and foam rubber sheet materials that are laminated with various other materials.

Traditional foamed Neoprene, is quoted at about 60% to 70% water impermeable. More recently, technology has allowed the figure to be pushed up to about 95%, by introducing various alternative or additive materials to the foam rubber manufacturing process.

The technology to laminate a thin water impermeable membrane onto a foam Neoprene sheet, during sheet material manufacture, has been around about as long as the Neoprene drysuit.

[Toblerone]

That was either a highly informative post or one of the best leg-pulls I've had in ages (and I've had a few!) :)

[ChristianG]

That was either a highly informative post or one of the best leg-pulls I've had in ages (and I've had a few!) :)
You're talking about Matt's post? Last time I looked he doesn't do leg-pulling all that well.

If you were referring to my post, the same applies. :D

[Toblerone]

Well, you've never had to hang a neoprene drysuit up to dry? Takes an awful long time, especially when compared to a trilam suit.

Yes it does (I've had two neoprene drysuits, one trilam and a breathable surface jobby) - but I'd always assumed that was because the nylon outer lining was wet. This thread has really opened my eyes. Thank you Christian.

[Spirit_of_Guernsey]

I am no physicist, but I don't get any squeeze, probably because it is tight fitting so little air to compress and is made from a thicker material so does not fold.

I used it right through last winter down to 35m in the English Channel, including being on the boat for an hour or two before and after the dives. The only bits that became at all chilled were my hands and feet but that is because of having wet boots and gloves.

[Spirit_of_Guernsey]

So to clarify, you are saying that my neoprene semi-dry is not as waterproof as a drysuit as a small amount of water can permeate the material, which is the same material that a lot of drysuits are made out of, therefore neoprene drysuits are really wetsuits fitted with an inflater and dump valve?

Also neoprene suits take much longer than a dive for the water to permeate them so the user can be completely dry at the end of a dive?

So if a diver can remain totally 100% dry after a three dive day, how can the suit be called a wetsuit?

[Richard Whitcombe]

A good fitting suit should touch you all over like a second skin. If it doesn't it wont work.

Water still gets in. A small layer of it but its still water. That's why its a wetsuit. Stitching lets in water, zips let in water, the seals let in water. Nothing in a wetsuit (and a so called semi dry is a wetsuit) is designed to completely block water.

You can't cheat physics, you cannot physically remove every single bit of air no matter what the fit. You WILL get squeeze.

[Spirit_of_Guernsey]

Water still gets in. A small layer of it but its still water. That's why its a wetsuit. Stitching lets in water,so the seams on a drysuit let in water? zips let in water, So the zips on a drysuit let in water? the seals let in water. So the seals on a drysuit let in water? Nothing in a wetsuit (and a so called semi dry is a wetsuit) is designed to completely block water.

You can't cheat physics, you cannot physically remove every single bit of air no matter what the fit. You WILL get squeeze.

Sorry Richard, your understanding of physics must be wrong. I have plenty of witnesses who have seen that I am bone dry after dives, many are shocked as they are certain that it is impossible, because that is what they have always been told.

John 20:19-29

[Mark]

Sorry Richard, your understanding of physics must be wrong. I have plenty of witnesses who have seen that I am bone dry after dives, many are shocked as they are certain that it is impossible, because that is what they have always been told.


Maybe not wrong, but badly applied.
Air in your wetsuit/semi will compress.
But that isn't suit squeeze.
Suit squeeze (or the perception of squeeze) is due to the inflexible nature of most drysuit materials. You need the air to allow the suit to move with your body. Remove (or compress) the air and you can't move.
However, a very flexible stretchy material won't need the air, and you then feel no effect of the squeeze.

Well, that's my thought anyway...

[Nigel Hewitt]

Maybe not wrong, but badly applied.
I have a freediving 'wet suit' that doesn't let in water.
Admittedly I have to put it on with lube (cheap Asda hair conditioner so I foam up in the shower afterwards).
It's spectacularly good in cold water although it needs 7Kgs of lead on the belt to dive it so that it goes neutral at 10 meters as it compresses.

At 30 meters I have so little air left in my lungs that my mask is beginning to squeeze because I can't relieve it any more but no squeeze in the vitals because it is already as snug as it can get. I think the problem with dry suits is that when they squeeze they crease up and it's the creases digging in that causes the angst.:eek:

The bonus with a tight suit like that is not just staying warm but after a week of that I might still be a bit thin on top but I have luxuriously silky body hair.:rolleyes:

[AndyOz]

I had a very bad case of suit squeeze on my back and legs when wearing a neoprene drysuit with an undersuit. I think it's as Nigel says that the areas where the creases/ridges form that dig in or pinch the skin, felt more like the latter. It was rather painful.

[AndyOz]

I never tried dry gloves but have seen them about, specifically the varied that lock into the drysuit cuff but the dry suit still has a suit seal. Users I've spoken too swear by them.
Presumably the wearer has to get most of the air out when putting them on, removing all of it would seem difficult. Are they not affected by suit squeeze?

[Nigel Hewitt]

I never tried dry gloves but have seen them about, specifically the varied that lock into the drysuit cuff but the dry suit still has a suit seal. Users I've spoken too swear by them.
Presumably the wearer has to get most of the air out when putting them on, removing all of it would seem difficult. Are they not affected by suit squeeze?
Exactly wrong. Dry gloves need to connect to your suit and stay equalised. You wear warm under-gloves.

Even Ice diving I've never seen the need and I get cold easily.

[Toblerone]

Exactly wrong. Dry gloves need to connect to your suit and stay equalised. You wear warm under-gloves.

Even Ice diving I've never seen the need and I get cold easily.

Dry gloves with wrist seals (as opposed to those used with ring systems) are made though (I have some that your wear fleece gloves underneath). They are advertised for diving use. I wonder how you get on with those at greate depths. Do you wear clothing that goes under your wrist seal to enable air to pass back and forth from the gloves?

[PeteM]

Do you wear clothing that goes under your wrist seal to enable air to pass back and forth from the gloves?

Normally a thin tube between suit and glove

[AndyOz]

Thanks guys.

Nigel, I've never felt the need for dry gloves either, unless contamination is an issue. I brought this up in case there was some arcane method being used to avoid the squeeze.

Maybe the 1-2 divers I've seen with the set up I described had them installed incorrectly or weren't clear describing what they actually did. They were going to the 30-40m range so squeeze surely would have been noticable. They definitely had the wrist seal on as well. PeteM's answer seems to be the logical one in this case.
I have seen other divers using dry gloves but I didn't see them putting them on so I don't know how they were set up.

PeteM, I suppose a small diameter tube wouldn't let much water into them suit if the glove was lost/punctured.

I have met divers you use "semi-dry" suits all year round in UK waters and swear they have never had water in the suit. I am sceptical as I've always had some moisture in my drysuit, be it neoprene/membrane etc, it's never been a problem though. My spearfishing suit definitely lets water in but is warm enough for purpose. To me whether you get wet or not is moot, are you warm enough on the dive and on the rib?
That's the fundemental question and at the end of the day we all differ, I seem to be more cold tolerant now than 20 years ago.

Hot water suit for the win! :)

[PeteM]

PeteM, I suppose a small diameter tube wouldn't let much water into them suit if the glove was lost/punctured.

The tubes I've seen used are like the tubes you get on a can of WD40. If the glove were lost you could just pull the tube out. If punctured I don't think significant water would get in as in a normal diving position your hands tend to be one of the lowest points on your body

[AndyOz]

Hi mate,

No I don't dive, just mooch around the shore/ rocks and only on holiday with family.

Actually probably the cheapest solution for that use might be to get a basic kayak cag or spray top. This will keep the wind off and they have neoprene/latex wrist and neck seals with an adjustable (often neoprene) waist.
If you aren't diving they should be fine. I've worn one over a wetsuit or farmer john pretty often when white water river swimming. Not as warm as a dedicated kayaking drysuit but more flexible and cheap.

[Richard Whitcombe]

There is no way in hell i could do any UK winter diving without my dry gloves. Without them id be in 20 minutes maximum than having to get out due to completely useless hands and be in burning agony from the cold.
Tried all the so called semi dry gloves, the 3 finger mitts and nothing stopped me being in pain after more than 25 mins.

With dry gloves im good for an hour or slightly more. To equalise i just use a bit of 5mm bungee that runs from inside the arm, under the latex seal and into the glove.