3mm vs 5mm?

[sourdough]

5mm with or without hood in 70-80. Hood depends on depth or whether I was to tuck in beard.

I'm only doing 1hr dives but sometimes start to feel chilly towards the end. Dive buddy is 7mm and always hoodied up.

 

[broncobowsher]

Your premise is faulty. You can NOT buy one suit to handle the temperature extremes that the various seasons and the geographic variations will impose.

Correct. You are looking at too broad of a range of temperatures for a single suit to cover it.

63° water is pretty chilly. You will find me in a drysuit (with a light undergarment) in those temps. 3mm is good for me in 85° waters. Even then I can get a little chill on a long dive. Adding a hooded vest won't fix a 3mm into a good 63° suit. Maybe if I am only in the water for 10 minutes?

 

[BoltSnap]

Indeed, Clinton MA is home. Lived in Maine for a few years after college. Depending on when you left I was probably still a kid

I was there on and off until circa 2010.

 

[thomasj1107]

So if you have on the 5 and are too warm, and open up, you don’t cool down?

 

[tbone1004]

So if you have on the 5 and are too warm, and open up, you don’t cool down?

Most all wetsuits are back zip because it makes them infinitely easier to get into and out of. With a BCD on it's not really possible to "unzip". Sure you can pull the neck seal and "pump" water into the suit and I do it every time I pee since the solution to pollution is dilution but it's annoying to try to cool off that way. With a 5mm you also have the extra lead to sink it flexibility loss for arm/leg motion. 3mm+hooded vest is much more versatile than a 5mm and if the 3mm and hooded vest are high quality you can't tell a difference between a 3mm+hooded vest and a 5mm in the colder stuff, but you absolutely can in the warmer stuff.

 

[BoltSnap]

So if you have on the 5 and are too warm, and open up, you don’t cool down?

Not really especially since you can't really open the zipper with the BC on. You need a 5mm suit for when the temperatures call for a 5mm suit and a 3mm suit when the temperatures call for a 3mm suit.

 

[broncobowsher]

You can tug the neck opening and have the suit take a gulp of cold water and let that flush through the suit.
But you don't just run the zipper up and down a little as you would a jacket walking down the street. Remember a wetsuit works different. It doesn't actually keep you warm, it keep the layer of water between it and your skin warm, so you are swimming in a very small pool of water heated by your body. That is why a good fitting wetsuit is important as is minimizing water flushing through the suit at the openings (hands, feet, neck, zipper, seams...) Break the neck seal and change out the water in the pool, yes that will pulse cool you. The skin. Takes a lot of those if the core is cooking. It can be done. Don't stretch out the seal or tear it.

 

[dflaher]

I prefer 3mm+hooded vest to a 5mm.

What thickness is the hooded vest?

 

[buddhasummer]

So if you have on the 5 and are too warm, and open up, you don’t cool down?

As long as sea water isn't bath temp, yes, if you pull neck open and let "fresh" water flood in it will cool you down somewhat. I respectfully disagree with the it's "BS".

I wear a 5mm with hood in the tropics, usually I'm just right, occasionally I get a little warm so flood suit with water and it does cool me down for a bit.

Would I recommend using a 2 piece 7mm farmer John in tropical waters hoping a flush of fresh water would cool me down? No. But for me in a not extreme water temp the difference between a 3mm and 5mm is not big. YMMV.

 

[DiveFlag = Target]

If you dive often and deep enough you can turn your 5 into a 3 eventually?