So what the heck is a semi dry suit?

[cmburch]

maybe I read that wrong. Did I offend you?

I am only trying to learn, sorry if that means I am posting for "self entertainment".

Some tend to associate learning with information exchange. Some SB forum members do it a little different by posting their opinions which may or may not contain useful information.

No offense.

It does look like you are posting your experience about wetsuits and would not have noticed any difference if you had not said differently in a separate post.

I was pointing it out. If it is for knowledge and not self entertainment:

There are certain applications where a wetsuit is used as the primary exposure suit and drysuits may not be considered. For freediving/SCUBA diving the California coast a wetsuit is good for most instances. Activity in the warm California sun from long surface intervals or long surface swims or strenuous activity can lead to overheating. A wetsuit can be cooled by letting water in. So on one hand can be freezing from 46-52F water and overheating from the sun depending on the situation. The extra material -seals around the ankles, wrists, face and zippers on the "semi-dry" adds more comfort and warmth. One may not consider a second exposure suit for cold water SCUBA such as a drysuit unless having problems with comfort. Kayak SCUBA diving can be hot even with a wetsuit, but a drysuit can also be used. Improper fitting wetsuits are not a good idea, as someone mentioned a suit is only as good as the fit and comfort levels and circumstances vary. So a wetsuit and drysuit have their uses depending on the circumstance. I would overheat hiking down cliffs and long surface swims, so a drysuit would have to be carried or the top zipped down while hiking and kayaking. I could not wear it zipped up to the shore or dive spot unless it was overcast or cool weather.

 

[fusioncruiser]

A semi dry is a wetsuit with a bigger marketing budget. You'll get just as wet and marginally less cold than a wetsuit.

Hate to disagree when I am not even Open Water Certified yet (one skill to go), but that hasn't been my experience so far....

I bought the Mares Isotherm semi-dry 6.5mm and of the 4 dives we did this weekend, my bathing suit remained dry on all but one of the dives (and in that dive it was my fault i got wet because I was playing with my neck seal when a boat wave caught me in the face and some went down the neck seal). So, i definitely could have worn a t-shirt without it getting wet at all if not for that one incident with me sticking my fingers down my neck seal. Next time I might even do the t-shirt thing. We dove in water that averaged 62F but a couple of times below the thermocline my gauge registered 52f and the isotherm kept me toasty warm through it all.

Gotta tell you I am impressed with it so far.

Just my 2 cents.

Shawn

 

[peterbj7]

It's actually intended that you get wet with a semi-dry. Otherwise it becomes a dry suit without any control over the air, and can subject you to great squeeze as you go deeper. But it sounds as if you have a particularly well-fitting one that should certainly serve you in good stead.

But I repeat my observation of several hundred dives around Britain - I have never known anyone wearing a semi-dry (properly, so they get wet) do more than one dive a day.

 

[BigFame]

It's actually intended that you get wet with a semi-dry. Otherwise it becomes a dry suit without any control over the air, and can subject you to great squeeze as you go deeper. But it sounds as if you have a particularly well-fitting one that should certainly serve you in good stead.

But I repeat my observation of several hundred dives around Britain - I have never known anyone wearing a semi-dry (properly, so they get wet) do more than one dive a day.

Well in that case I hope I can make it through my OW classes in two weeks in my 7mm.

;-)

 

[TSandM]

You'll make it through your classes, BF, in part because the dives are pretty short. 20 to 25 minutes is typical. When you actually go DIVING (rather than skills demonstrating), most people try to stay at least 45 minutes in the water, and there's a HUGE thermal difference.

 

[fusioncruiser]

It's actually intended that you get wet with a semi-dry. Otherwise it becomes a dry suit without any control over the air, and can subject you to great squeeze as you go deeper.
But I repeat my observation of several hundred dives around Britain - I have never known anyone wearing a semi-dry (properly, so they get wet) do more than one dive a day.

I am learning all the time..... Could you please point me to some online referrence to the fact that you are supposed to be wet in a semidry if you are using it correctly. I would greatly appreciate it. Also anything you may have explaining how lack of water in the suit would contribute to a squeeze if water is incompressible and you burp all the air out at the beginning of the dive.

I appreciate the help on my learning curve.
Shawn


k

 

[almitywife]

ive been diving in a semidry for almost 10yrs now

you are suppose to get wet in a semidry, after - its still a wetsuit just has different seals/construction

the plus to a semidry is water is trapped inside the suit so once my body warms it up it isnt wasting energy constantly trying to heat up cold water being flushed thru the suit (like you do with a standard 2 piece suit). what i usually do is when i get in the water i crack open the seal and let some water in and thats it during my dive. other divers (ie hubby) just go diving and small amounts of water gets into suit but the when taking the suit off the water is usually quite warm

down here, seatec is where you go to get a good suit; Predator & Predator Pro Semi-Dry Suit

as you can see by the pic (the site wont let me put the pic up here), the "cone seal" on the feet and wrists are what seals the suit against constant water flow. the neck is a seal but not so firm that it squeezes you and here is where any water gets in

cheers

 

[String]

t that hasn't been my experience so far....

I bought the Mares Isotherm semi-dry 6.5mm and of the 4 dives we did this weekend, my bathing suit remained dry on all but one of the dives (and in that dive it was my fault i got wet because I was playing with my neck seal when a boat wave caught me in the face and some went down the neck seal). So, i definitely could have worn a t-shirt without it getting wet at all

The number of times ive heard that and its incorrect. A drysuit is sealed. Because of that it has to have valves to allow air in and out to prevent squeeze. If this wetsuit was "dry" you'd be suffering from squeeze, reduced mobility, bruising and discomfort just as you would in a drysuit. There is a gap so water gets in - there has to be to avoid that - the air has to be replaced by water. Clothes dry fairly quickly especially when next to a body but they still get wet.

But I repeat my observation of several hundred dives around Britain - I have never known anyone wearing a semi-dry (properly, so they get wet) do more than one dive a day.

Similar experiences here. On lots of trips/charters which are standard 2 dives a day for 2 days in a row you typically see the wetsuit people doing the first dive of the day and sit out the 2nd. They then do the 1st dive of the day on the 2nd tday and not the 2nd. So in reality they are paying twice as much per dive as everyone else as they only get half the number. When a weekend trip with fuel, accommodation, boats, gas can cost £300 its a hell of a per dive price!

Ive seen many students trained in wetsuits in quarries who hate it so much they vow never to dive again. Ive seen people so cold they're unresponsive and in a dangerous state. This time of year you MIGHT get away with wet students as sea is about 15c and quarries 18-16c in the shallows. However thats only about a 2 month window in the entire year and even then assumes its not cold or wet during the SI so they can warm up (so that rules this year out then!).

Also anything you may have explaining how lack of water in the suit would contribute to a squeeze if water is incompressible and you burp all the air out at the beginning of the dive.

Firstly you dont/cant remove all the air short of plugging yourself into a vacuum machine. There will always be a gap between the suit and your skin unless you glue the thing on. On the surface that gap is air. If that was then a perfect seal you go underwater, the pressure squeezes the air causing all the suit squeeze problems that drysuits have. However, they aren't a perfect seal so that small air gap is replaced by water which cant be compressed therefore is not affected by the external pressure so therefore cannot squeeze.

It'd be great if you didnt have to do anything about air trapped in a suit - drysuit diving would be a lot easier!

 

[old gaffer]

Beg to differ on the 1 dive a day semi-dry wetsuit thing. I went diving on Lake Superior with water temp at 41 degrees. 3 of us had wetsuits and 2 had dry suits. we did 3 dives that day of 35 to 45 minutes each and the 3 of us using wetsuits did get cold and It took us awhile to warm back up between dives but it did not stop us from diving. I guess it is just what you get used to.

Gaffer

 

[String]

Some people are more tolerant to cold than others. Well over 90% of wetsuit people i see do 1 dive then stop per day. In winter its nearer 100%.