thermal protection question

yousmellsfishy

New member
I have just completed the classroom/pool part of my open water class and will be going on a liveaboard dive boat Cat Ppalu in the Bahamas 3-28-09 for a week for my cert dives and first diving experience. Their website recommends a full 6 mm wetsuit for that time of year there, but my LDS, who's putting the trip together and has been there many times before are saying a shorty will be plenty (surprizing that they're not trying to sell me more protection). I'm 6'1" and #260 so I have a substantial amount of... uh.. built in insulation. On land I have a high tolerance for cold, and kind of a poor tolerance to hot. What would you advise? My plan for future diving is going to be mostly carribean in winter (Bonaire, Honduras, etc.)
 
I don't know why anyone in the dive industry would recommend a 6mm suit - generally, the majority of manufacturers offer suits in 3mm, 5mm, and 7mm thicknesses. Ocassionally you'll also find 1mm suits designed to be similar to a "skin," which is like a spandex body suit.

I hear a lot of divers who haven't dived in a long time refer to the "1/4 inch" wetsuit... Perhaps this is the way they used to be sold, but I have never seen a manufacturer refer to suit thickness in anything other than millimeters.

When asked, I always recommend against "shorty" wetsuits. Wetsuits do more than simply offer thermal protection - they also protect the diver from fire coral, jellyfish (which are sometimes too small to notice) and other marine nasties. Keep in mind that a diver is completely submerged underwater for the duration of the dive, and feels the effects of water cooling the body moreso than a surfer or swimmer does. He also breathes cold gas that's just been uncompressed... And remember, if the water temperature is below 98.6 degrees, you can become hypothermic in it - in fact, you will... It's just a matter of time. When the water is 86* and sunny, hypothermia seems far, far away... But after just a few hours of diving, even the most prepared diver can still get hypothermic.

For diving in waters above 75* or so, I would recommend a 3mm full suit. For anything less I would dive dry - although a 5mm wetsuit can also work well down to about 65* if the diver wears a hood. A 7mm full suit is a "not bad" solution for waters down into the mid 50's, at least for short durations. I ocassionally dive a 7mm full suit into the upper 40's - but I wouldn't recommend it.

Personally, my favorite wetsuits are those made by O'Neill - they have a "Sector" line with fully taped seams and stretch neoprene in key places that make the suit very comfortable. It's also lined with fleece, which can be really nice. O'Neill seems to have cornered the market on fit - fit can be so good sometimes that after the dive, the diver removes his wetsuit to find that it's only minimally wet on the inside... Meaning that water flow was kept at a minimum (the secret to making a warm wetsuit).

O'Neills can be tough to come by - they're not part of the standard dive shop regimen (not carried by the "manufacturer's rep" rapists), so finding them can be a tough thing to do. Thus, allow me to give a plug to Dennis at Austin's Diving Center in Miami, Florida... He's an O'Neill dealer that's really "on the ball."

When you get your O'Neill, you'll find that there's not a straight seam on the suit - they're all curved, which is a great thing... That's one of the secrets of their awesome fit. I don't know of another suit that is built quite like that.

I hear good things about Body Glove, but my experience is that O'Neill makes a higher quality suit. Pinnacle seems to have a good reputation, too, especially with their new Marino lining (wool). I have no experience with Pinnacle, but know that ScubaPro's suits seem to wear out quickly and that Henderson makes suits that are totally overpriced and are usually overly stretchy (good for fit, bad for wear and thermal protection) to compensate for the fact that their suits fit horribly in the first place. Harvey, Akona and Deep Sea all seem to have "generic" build quality at best, combined with a terrible fit.

Based on what I'm reading, I think I'd recommend a 3mm "Sector" full suit with an optional hood if the water temperature drops below 78* or so. Call Dennis.
 
i agree, i would never wear a shorty. If you are going to be doing 4 dives a day for a week i would get cold in a 3mm. go with either a 5mm or a 3mm with a core warmer.
 
I live close to there (Sunrise is about a 2-3 hour boat ride straight east), and also have some nice insulation, when I was collecting for a living we were in the water for 5+ hours a day, and even in the summer when temps were in the 80's it drains you and you don't want to dive while uncomfortable. As others have said, full suits do more then keep you warm, there are lost of things that sting and even a skin will protect you. What I do that time of year is wear a 3/2 with a hood, but you may want to go with a 5 mm only because you don't want to miss out on the experience by skipping dives. I can't stress how uncomfortable it is to be diving while cold and for a trip like that you want to be in the water every chance you get. Your other option is to have more then one wet suit, that is what I have, but I dive every day the weather allows, some years up tp 300 dives, so I have to be prepared.
 
<a href=showthread.php?s=&postid=14198329#post14198329 target=_blank>Originally posted</a> by SeaJayInSC
I don't know why anyone in the dive industry would recommend a 6mm suit - generally, the majority of manufacturers offer suits in 3mm, 5mm, and 7mm thicknesses. Ocassionally you'll also find 1mm suits designed to be similar to a "skin," which is like a spandex body suit.

I hear a lot of divers who haven't dived in a long time refer to the "1/4 inch" wetsuit... Perhaps this is the way they used to be sold, but I have never seen a manufacturer refer to suit thickness in anything other than millimeters.

When asked, I always recommend against "shorty" wetsuits. Wetsuits do more than simply offer thermal protection - they also protect the diver from fire coral, jellyfish (which are sometimes too small to notice) and other marine nasties. Keep in mind that a diver is completely submerged underwater for the duration of the dive, and feels the effects of water cooling the body moreso than a surfer or swimmer does. He also breathes cold gas that's just been uncompressed... And remember, if the water temperature is below 98.6 degrees, you can become hypothermic in it - in fact, you will... It's just a matter of time. When the water is 86* and sunny, hypothermia seems far, far away... But after just a few hours of diving, even the most prepared diver can still get hypothermic.

For diving in waters above 75* or so, I would recommend a 3mm full suit. For anything less I would dive dry - although a 5mm wetsuit can also work well down to about 65* if the diver wears a hood. A 7mm full suit is a "not bad" solution for waters down into the mid 50's, at least for short durations. I ocassionally dive a 7mm full suit into the upper 40's - but I wouldn't recommend it.

Personally, my favorite wetsuits are those made by O'Neill - they have a "Sector" line with fully taped seams and stretch neoprene in key places that make the suit very comfortable. It's also lined with fleece, which can be really nice. O'Neill seems to have cornered the market on fit - fit can be so good sometimes that after the dive, the diver removes his wetsuit to find that it's only minimally wet on the inside... Meaning that water flow was kept at a minimum (the secret to making a warm wetsuit).

O'Neills can be tough to come by - they're not part of the standard dive shop regimen (not carried by the "manufacturer's rep" rapists), so finding them can be a tough thing to do. Thus, allow me to give a plug to Dennis at Austin's Diving Center in Miami, Florida... He's an O'Neill dealer that's really "on the ball."

When you get your O'Neill, you'll find that there's not a straight seam on the suit - they're all curved, which is a great thing... That's one of the secrets of their awesome fit. I don't know of another suit that is built quite like that.

I hear good things about Body Glove, but my experience is that O'Neill makes a higher quality suit. Pinnacle seems to have a good reputation, too, especially with their new Marino lining (wool). I have no experience with Pinnacle, but know that ScubaPro's suits seem to wear out quickly and that Henderson makes suits that are totally overpriced and are usually overly stretchy (good for fit, bad for wear and thermal protection) to compensate for the fact that their suits fit horribly in the first place. Harvey, Akona and Deep Sea all seem to have "generic" build quality at best, combined with a terrible fit.

Based on what I'm reading, I think I'd recommend a 3mm "Sector" full suit with an optional hood if the water temperature drops below 78* or so. Call Dennis.
SeaJayInSC thank you for your thoughtful and knowledgeable answer. I will look in to the Oneill suits.

<a href=showthread.php?s=&postid=14201959#post14201959 target=_blank>Originally posted</a> by fishome25
i agree, i would never wear a shorty. If you are going to be doing 4 dives a day for a week i would get cold in a 3mm. go with either a 5mm or a 3mm with a core warmer.

<a href=showthread.php?s=&postid=14203040#post14203040 target=_blank>Originally posted</a> by snorvich
Agree with above. 4 dives per day can really drain your body heat.

<a href=showthread.php?s=&postid=14204070#post14204070 target=_blank>Originally posted</a> by philter4
I live close to there (Sunrise is about a 2-3 hour boat ride straight east), and also have some nice insulation, when I was collecting for a living we were in the water for 5+ hours a day, and even in the summer when temps were in the 80's it drains you and you don't want to dive while uncomfortable. As others have said, full suits do more then keep you warm, there are lost of things that sting and even a skin will protect you. What I do that time of year is wear a 3/2 with a hood, but you may want to go with a 5 mm only because you don't want to miss out on the experience by skipping dives. I can't stress how uncomfortable it is to be diving while cold and for a trip like that you want to be in the water every chance you get. Your other option is to have more then one wet suit, that is what I have, but I dive every day the weather allows, some years up tp 300 dives, so I have to be prepared.

fishome25, snorvich, Philter thanks for your replies. Good points to consider. To be honest, I've been a little overwhelmed with the cost of all the pieces of equipment. BC, reg, computer, suit, holy cow!! I know quality is important but I'm trying to go on this trip and still have a pot to pi$$ in. My LDS will rent everything I need, but I was thinking of purchasing the wetsuit before I go.
Lots to consider
 
Ha! Oh, we're with you on that... And I often see the new diver go out and blow more than a few thousand dollars the moment he gets certified. This tendency is what keeps the dive shops going - they really don't make a whole lot of money on classes and tank fills.

The problem with the concept of placing so much emphasis on profiting from the sale of gear is that it's not in the best interest of the new diver to spend a bunch of money the moment he or she is certified - firstly, the new diver isn't going to have enough experience yet to be able to make informed, educated decisions on the type of gear they're going to want (they haven't even established what sort of diving they're going to want to do yet). Secondly, bleeding the new diver of a bunch of funds certainly will curb diving - many divers get frustrated quickly with the cost and complications of diving, combined possibly with poor gear choices, and decide that it's not really something that they want to pursue passionately. The result often is a closet full of practically new gear that gets dived two or three times and then stuffed in a closet somewhere. When you ammortize the cost of that gear splurge over the cost of two or three dives, it's easy to see why a lot of people drop out of diving and don't return for years - or at all.

...So in reference to gear, I recommend purchasing your own suit, mask, fins, booties and hood. The rest of the gear, I believe, should be rented until you've fallen in love with something that you simply can't live without. It'll add to the cost of each individual dive initially, but it'll give you a lot of experience with various pieces of gear so that you can see what's good and what's not so good - and there is a lot of the latter in the scuba industry due to the fact that the manufacturers know that most sales are made to newbie divers who simply don't have enough experience to know any better.

There's also a problem with purchasing gear that you simply don't know about yet... We, at my commercial dive operation call it, "Surface Logic." Probably 90% of the things found in your average dive shop look like a really great idea when you're in the shop - but are a horrible idea underwater for reasons that are not obvious until you're actually diving with the item. Let me be clear on this: The manufacturers are fully aware of this, and do not build gear to work well underwater - they build gear that is appealing in the dive shop so that it will sell.

A good example of this is any BC that does not have a built-in crotch strap. Place one of these on in the store, and the fit and finish appear wonderful and it's easy to see why, with workmanship and quality, a certain BC can be priced at $600 or $700 for the best ones. Some even have "elevator buttons" or levers that are sexy and attractive and appear to be a great idea.

Underwater, the reality is that, depending on where your weight is kept, your BC is constantly pulling up on you, especially when you're near the surface. If there is no strap to keep the BC down on your back, it will bunch up and ride up and be uncomfortable - which has absolutely nothing to do with how much padding is in it (another "Surface Logic" item). But you wouldn't know it unless you've tried it, and of course, that won't be until after you've paid for it.

More examples of "Surface Logic":

Any fin with plastic on it.
Quick releases on your fins or BC.
Plastic anything.
Clear-skirted masks.
Masks with more than two pieces of glass in them.
Masks with curved glass in them.
Any BC with no hard internal structure in it.
"Farmer John" wetsuits.
Any BC that "wraps around the diver" and doesn't wrap around the tank.
Any underwater light with a pushbutton switch.
Any underwater light that occupies a hand and can not be stowed.
Split fins.
Spare Airs.
Regulators with "turrets."
Hose protectors.
Tank protectors.
Most of the things on the Trident accessory tree in the shop.

...And the list goes on.

Literally, you could walk into the dive shop and blow thousands of dollars and not buy one useful scuba item - in fact, I think it'd be more difficult to go in there and buy only useful things.

Now certainly I'll get blasted for saying this on a public forum, but nonetheless that's the truth.

For now, focus on your mask, fins and suit. You've seen my recommendation for a suit - for a mask, consider only those that are available in a black skirt - clear skirts are for snorkeling, "ghost" while at the surface, and yellow in a matter of months unless they're stored in a closet and not actually used. Look for a mask that only has one or two pieces of glass in it - anything more is "Surface Logic" and will only serve to give you odd, distorted images underwater - something that you won't find until you're actually using the mask underwater. The viewing port of the mask should be as close to your eyes as possible, and as close as is comfortable (if your eyelashes hit the glass, it's too close - everything else is fine).

Fins - Plastic sucks because it fades and becomes brittle and weak with both cold and sun. Avoid split fins - beware of the Surface Logic that says that you want the "fastest fin possible" with the "least effort possible." The important thing underwater is precision, and your ability to use a variety of kicks very precisely. Big, floppy fins don't do that, even if it were true that they were faster.

...Which they're not. Beware of the "Surface Logic" that says that "these fins are great, but don't do well in current." The fins have no idea whether they're in current or not - either they're good at propelling or not. Someone who tells you that "these fins aren't any good in current" is telling you that these fins suck and that they don't have any idea what they're talking about.

Divers who have thousands of dives under their belts wear ScubaPro Jet fins. They are short, stiff and heavy - none of that is sexy in the dive shop, but underwater they're awesomely precise, heavy enough to not require ankle weights (another "Surface Logic"), and have no plastic parts to wear out or fade. They'll literally give you decades of service without failure, and can be had on eBay for pennies.

Don't worry about your BC, regs, tanks, or assorted crap just yet - you'll have plenty of time to amass all that junk later.
 
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My pleasure - there's not much I'd rather talk about than scuba. :)

It looks like you're getting a ton of great advice from everybody.

With real estate, they say it's "location, location, location." When it comes to masks, it's "fit, fit, fit." :)

If I were new in the industry and didn't know which masks fit me already, I would hit a few big dive shops and find one that really fit nicely. Remember the black skirt thing (just the fact that they don't yellow over time is a great thing) and that the best masks are those that are single and dual lens masks. From there, it's fit - if you find two that fit the same, choose the one that holds the glass closer to your face, for it will be less buoyant (smaller volume) and therefore pull up on the bottom of your nose less... Making it more comfortable, especially on long dives. The best masks that come to mind for me are two or three models made by ScubaPro, two or three made by Halcyon, a mask or two made by Mares, and two or three made by Atomics. You'll find that many of these masks are virtual clones of each other with only a few small differences - plus a considerable difference in fit.

Once you find the mask that you fall in love with, search for price. I've seen prices on Leisurepro.com and DiversDirect.com that are 1/3rd the price of your local dive shop... Even less on eBay. Yes, it's true that if you buy on eBay, it's probably used, and therefore won't fall under manufacturer's warranty. Leisurepro has an in-house warranty that's probably better than the manufacturer's, and many other online stores DO have the manufacturer's warranty attached... Be prepared to be BS'd by the local dive shop about warranties, and why you need to pay twice the price to buy the same item from them. Support your local dive shop if they don't BS you, give you completely false information, or charge twice the price for the exact same item online.

For fins, I - and many other professional scuba divers - are totally sold on ScubaPro's "old fashioned" Jet Fin (not the "twin jets") because of their stiffness and precision - which gives awesome control and as much speed and/or torque as your legs can possibly generate, when the need actually arises to swim-like-hell. You'll really appreciate the short, stiff blade when hovering over fragile coral reefs, around wrecks and in caverns, which can all be very sensitive to a misplaced kick. If you find the Jets too military-esque, consider Mares Quattros - they're also very good, although there's a lot of plastic on them, they're considerably longer and more flexible (thus harder to control the tips) and have quick release buckles, which are unnecessary and prone to breaking after a year or two. Avoid split fins - they're like swimming in sneakers, and about as efficient. Yes, it may be true that with the right kick you may be able to get speeds out of them similar to a paddle fin, but with four fin tips to think about, it's very easy to kill a decade of coral growth in one dive... And feel totally out of control while doing it. There is no magic when it comes to fins - they all dive exactly like it looks like they'd dive. And yes, splits are a lot easier to kick, largely because they flop over and do nothing when you kick them, rather than moving water and propelling the diver. Don't let some dive shop nubbie tell you that there's some sort of scientific magic and that suddenly you'll be both faster and more efficient. That's "Surface Logic."
 
SeaJayInSC has a lot of good advice there. But keep in mind everyone is different. I would never use jet fins again. I love my appollo bio fins (split fins). They are no gimmick.
 
Expect water tems in the 68 to 74 degree range. For me, that's a Dry Suit or 7 mil, but everyone is different. Usually newer divers have more adrenaline and spend more energy swimming around, thus generating heat.

Good luck and enjoy the trip
 
I have a 1mm skin that I use when cleaning aquariums, but I'm now needing to buy a suit for regular diving...

Would you guys suggest a 5mm or a 7mm as a best "all-around" wetsuit, and why..?

I'm kinda leaning towards the 5, and I could always wear the 1mm under it if absolutely necessary. I also have a full set of Capilene long underwear that I used to wear under a Farmer John when I worked as a raft guide.

-Tim
 
<a href=showthread.php?s=&postid=14198329#post14198329 target=_blank>Originally posted</a> by SeaJayInSC
I hear a lot of divers who haven't dived in a long time refer to the "1/4 inch" wetsuit... Perhaps this is the way they used to be sold, but I have never seen a manufacturer refer to suit thickness in anything other than millimeters.

Indeed that is how they were sold back in the day. My first wetsuit was a 1/4" farmer john :D Now days I have a 7mm full suit and a 7mm hooded vest that I add on when the water dips into the mid 50's. That combo keeps me toasty down into the low 40's :) For the tropics this time of year I wouldn't use anything more than a skin, but I'm also acclimated to northeast Atlantic waters.
 
<a href=showthread.php?s=&postid=14230355#post14230355 target=_blank>Originally posted</a> by tgreene
I have a 1mm skin that I use when cleaning aquariums, but I'm now needing to buy a suit for regular diving...

Would you guys suggest a 5mm or a 7mm as a best "all-around" wetsuit, and why..?

I'm kinda leaning towards the 5, and I could always wear the 1mm under it if absolutely necessary. I also have a full set of Capilene long underwear that I used to wear under a Farmer John when I worked as a raft guide.

-Tim

A lot depends on where you plan to do most of your diving. For me a 7mm full suit is the choice. In the summer I don't wear a hood or neoprene gloves. When the water starts dipping into the 50's I add on the earlier mentioned 7mm vest. Typically my local water temperatures peak around 68-70 late in the summer, with most of my diving season spent in water around high 50's and low 60's. If your water temps range warmer than that, the 5mm is probably a good choice. Vests/core warmers can also be added on top of a full suite to extend the comfort range.
 
I agree that a "good, all-around wetsuit" depends largely on where you're diving. I always felt that really great 3mm suit was a basic staple, and that other thicknesses were for colder waters - but our water temps here in SC run from 50* to 86* on average, with the upper 70's being most of the Spring and Fall.

If this is your average water temp (or higher), then I'd go with the 3mm as a basic staple, and add a hood or hooded vest for lower temps down into the low 70's or upper 60's, depending on how warm your suit is. Anything averaging lower temps should be a 5mm suit, IMHO.

Before you think, "Hey, I'll just go thicker just in case," keep in mind that there's a lot of value in minimizing how much suit you're wearing... A suit that's less thick is easier to dive and requires less weght, because it's less buoyant. It's also easier to get in and out of, and is less costly as well... So minimize your suit, but getting cold during the dive sucks. :)
 
We have mostly freshwater lakes and springs up here, so I'm thinking the 5mm will most likely be the best way to go...

-Tim
 
I think most of the advise that you have been given thus far is spot on.

From one not so skinny man to another, I would definitely suggest buying a suit before you go. In my experience, the suits that dive shops have on hand for large guys tend to be old, are often torn, and are generally just worn out. The comfort of a suit that you picked out is definitely worth it. Nothing is worse than having a suit that pulls in the wrong areas. You could end up coming off your trip with some chafing in areas that shouldn't be chafed.

I would also follow SeaJay's advice and purchase your own mask. Essentially he has hit it all right on the head and I don't have anything to add on that subject.

A great mask and comfortable suit go a huge way towards one great dive, let alone four per day.
 
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