dry suit thermals or semi dry wetsuit

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when I was doing OW/AOW in Southern California I found I was consistently too cold in rental 7mm with a hood. Even putting a 2mm shorty under the 7mm I still was uncomfortable past the first thermoclines. These dives where all 60-90 Feet and 55-65 Fahrenheit for about an hour. The instructor wore a dry suit. I'm pretty broke right now so when it came time to purchase my own suit I didn't want to buy twice. I got lucky and my lds just happened to have a aqualung solafx for me to rent. I thought 'semi-dry' was a marketing gimmick, until I actually jumped in the water. My suit fits well, so I only feel the suit flush up too the wrist and ankle seals when jumping in. No more flush of cold death down the spine. During a dive I don't even think there is much if any water exchange. Really this suit has made SoCal waters an enjoyable experience rather than the hypothermic endurance test it used to be.

I have since bought my own aqualung solafx and have 5 dives on it: the coldest my computer recorded was 60. I was super warm and relaxed throughout the entire dive and feel like I can absolutely recommend it down to 55 F. Some might even be fine down too 50. Either way this suit makes me feel like a true dry suit is no longer neccesary for these waters to be fun.
 
for my open water i rented a 7 mm john with 7mm jacket .14 mm at the core.first question will a 1 piece semi dry wetsuit be warmer than the previous i rented second if i were to buy a dry suit is there a big difference in the thermal underwear you buy at a dive shop compared to thermals you can purchase for snowmobiling other than a "bare "name and a few hundred dollars more

I find a issue with modern wetsuits is that they are 'flexible' and 'easy to move in'. Inherently this means they have more air in the neoprene and compress significantly at depth and lose thermal capabilities. I have a 7mm and feel that it probably ends up about 4mm at 20m, this is evident though buoyancy, I have to add a lot of air to the BC and changes in depth require compensation. The 7mm is colder than an old 'stiff' 5mm. Free divers tend to use less flexible suits to minimise this.

So will a semi-dry be warmer than the two piece who knows! A key factor will be the fit. Any suit that does not fit well will be cold(er).

I have a range of suits, 3mm, 5mm, 7mm and dry. I also have some wet layers, Lava core with hood or just a hood, or no hood.

My wife moved to a dry suit a few years ago and bought the 'snow suit' one-piece layer. It was low cost and effective, but, does not have the wicking effect, when damp is cold and needs to loft up so needs air in the drysuit. We both recently bought Hollis 450 undies and she will not go back to the 'snow suit'.

...between dives on the surface that it felt chilly .so the big question would be will i get my moneys worth out of a drysuit because on top of the suit you need thermals and take a drysuit course or just go with a semidry ,decisions decisions ,thanks

A key advantage of the drysuit is out of the water. Typically we would use a spay jacket over the wetsuit to keep the wind chill out. With a dry suit we just add some air (inflate) and the suit protects us from the wind/rain... If to warm open the zip a bit (while on the boat!). I have seen divers go hypothermic between dives, the mental state deteriorates and they can only focus on trying to get warm. This is not a safe situation and one that leads to aborting dives.

There seam to be a lot of hardy divers here, being comfortable at 55f. I tend not to use the word comfortable, I like to be warm, I will use the dry suit at 20C (~70f). I know we all react differently to cold and feel cold differently. Those with a bit of weight tend to be warmer (we call it bio-prene). My wife and I do not have much bio-prene!

I have just come back from the Galapagos, and was with 15 other divers and 2 guides. Most divers were in 7mm one piece wet or semi-dry. When the water hit 17C (~63f) all were cold and many skipped dives. The guides dived dry as did my wife and I. When we hit 14C (~58) on a dive 30+meter deep, all were very cold some aborted the dive and only a few did a second dive. My wife, the guides and I were all warm. I dived over 40m deep (~130ft) and felt no cold.
 
You'll dive a lot more and enjoy it more in a drysuit.
 
I had a 7mm Henderson semi-dry suit and that wasn't warm enough for me so I started wearing thermal fleece under the semi dry suit and it made a world of difference. I bought expensive kayaking Mysterioso heavy weight fleece that was mean for wet conditions. It took me to 49 bone chilling degrees. Turns out it was similar to dry suit fleece, so when I got my neoprene dry suit I stayed with the Mysterioso as an undergarment for temps between 55-65. Below that I use the onesie and when it is between 70 and 60 I just wear a wicking running shirt and bike tights underneath.
 
cool general census is go with dry now the next question is how difficult was the transaction from wetsuit to drysuit figuring out your buoyancy so far i have 4 open water dives obviously a new open water diver and with a 7 mm john and 7 mm jacket i found it a little difficult controlling buoyancy and i know its going to take practice ,willl a drysuit be easy transition
 
At this point I would expect you could reasonably expect to reach the same level of control fairly fast. The better you are the harder it is to reach that same level, so if you are sure you are going to do cold water diving I'd go DS sooner rather than later. But it's a lot of money, so be sure. Everyone who dives a drysuit has some interesting oopsies that they have experienced, so don't get too concerned if the first dive or two is a complete goat rope.
 
I'm doing dry suit with my OW. In some places, diving dry is the only thing people know.
 
At this point I would expect you could reasonably expect to reach the same level of control fairly fast. The better you are the harder it is to reach that same level, so if you are sure you are going to do cold water diving I'd go DS sooner rather than later. But it's a lot of money, so be sure. Everyone who dives a drysuit has some interesting oopsies that they have experienced, so don't get too concerned if the first dive or two is a complete goat rope.
well im up in sask canada and the dive shop here has some great deals on some gently used dry suits not nuch more than 2 piece 7 mm wets and i was told thermals that we use here for winter would do suffice for diving so i am definately leaning this way and love the goat rope lol
 
Dry suit for sure! My thermals that I use for snowmobiling are not good enough for keeping me warm in my drysuit. I normally am not doing much work while diving but sledding in the mountains makes me pretty sweaty. But it depends on what type of drysuit you get.. the top half of mine is trilaminate so I have the DUI XM 450. I wear my snowmobiling base layer under that for wicking. It has kept me comfortable at 36F water temp
 
cool general census is go with dry now the next question is how difficult was the transaction from wetsuit to drysuit figuring out your buoyancy so far i have 4 open water dives obviously a new open water diver and with a 7 mm john and 7 mm jacket i found it a little difficult controlling buoyancy and i know its going to take practice ,willl a drysuit be easy transition

You are at the learning stage and not yet gained the full set of skills to be at home underwater. Now is therefore a good time to gain the skills for drysuit diving. You have not yet learned any bad habits. Like virtually every new diver you are almost certainly overweighted - the training system tends to turn out divers that overweight.

There are a few people that think it is a bad idea to start drysuit early. The belief is that new divers like yourself cannot cope with two sources of buoyancy, the BCD and the drysuit. A lot of drysuit courses will therefore teach you (wrongly) to use only the drysuit and just use the BCD on the surface. If you do such a course you will find one of two things. If you have a good fitting neoprene suit the buoyancy will be easy - the "feel" of the air in the suit actually makes it more intuitive in my view - that was my experience doing the PADI Drysuit course immediately after my OW (also about dive #4). If you have a badly fitting suit your buoyancy will be all over the place.

The preferable method is to use the BCD for buoyancy as you have already been taught. Just take off the squeeze with the drysuit and use the auto-dump to exhaust the gas on the ascent. If you can find someone to teach you this and will also spend a bit of time on getting you correctly weighted you will quickly pick up the buoyancy control needed for pleasurable diving. A lot of the commercial drysuit courses will overweight you and want to use the drysuit as the bcd rather than the stab jacket as the bcd. For some reason overweighting becomes even more of a problem once divers start with a drysuit in my experience. Nearly everyone dives dry here and some people carry enough weight to sink a ship.

Getting comfortable in the water is as much about experience as it is training. You need the training and knowledge to understand what to do, but the experience is what you need to make that skill second nature. Much like learning to ride a bicycle, at some point your subconscious just "gets it" and you wonder why it took so long. Buoyancy is much like that. In the first instance you put in or dump too much gas - you overcompensate. Then you ascend or descend faster than you wanted so you adjust again, making it worse. Relax, take it easy - experiment a bit and ensure you both add and dump gas gradually, slowly. It will soon come together and be easy.

I would say therefore if you want to move to a drysuit go and get on with it. Sooner better than later. Start with the method that you will use going forward. I got so cold doing my OW that I knew I had to buy a drysuit. I bought a secondhand one from the dive shop and got the course for free. My first dive as a certified diver was my drysuit course. I have dived dry ever since. If my memory is correct the first "wet" dive was about 15 years later on holiday when I rented a wetsuit. It was cold. If that is scuba diving I would have given up a very very long time ago.
 
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