This your first and only post? Well, welcome to Scuba Board! :hi: Hope you enjoy it here. I do, I've learned much, and I've only incurred a few insults.
( By the way, you're also welcome to introduce yourself in the Intro Forum, where we can welcome you more completely?! )
But to your question: That's about the way I approached it. Now, my personal chill factor varies somewhat at my age, but I knew these basics from my years of tending cattle on open pasture in winter storms and such:
(1) Layering works well; 2 + 2 is approximately 4, even though not identical;
(2) As much heat can be lost out of the head as from the body trunk, making good head gear as important as a jacket - which is why you very seldom see any outdoorsman bareheaded; and
(3) If I just get chilled, I feel it in my shoulders first*, which is why a vest is so popular with outdoorsmen.
Most of my diving is done in waters from 72 to 82 F, with rare exposures to 52 to 72 F, so I keep a variety of combinations on hand:
(a) Warmer waters and warmer SI air temps, I'll wear a long "rash guard" skin and beanie;
(b) If either is cooler, I'll substitute a 1 mil equivalent skin with velour lining - especially with multiple dives over multiple days.
(c) Any colder, and I'll add light weight gloves and a 3 mil long over the 1 mil, giving me 4 mil over all, plus substitute a neoprene beanie for better head protection.
(d) When I go to California, I'll substitute neoprene gloves and add a 3 mil short on top of the 4 mil long combo above, giving me 4 mil on the extremeties but 7 mil on the trunck - even though I may dive with a native Californian wearing 3 or 4 mil, as he's just used to it.
* I considered the Farmer John (which this country boy would describe to a non-diver as suspender coveralls with a long coat), but saw that I'd have half as much protection on my shoulders as my trunck and butt and rejected that totally. I understand that this apporach is popular with many, but based on my logic - I just don't get it, and I've never seen any studies. I don't know the origin of the FJ, so while it's commonly accepted, I question its utility.
Quoting you here:
"5mm jumpsuit, and have been considering buying a 3mm (eg Henderson Hyperstretch) to put over it rather than buying a 7."
If you have a 5 mil long, and added a 3 mil short, you'd have about 8 mil on the trunck with 5 mil in the extremities, and bein gused to cold water anyway - be ready for pretty much anything a 7 mil might do. I'd
not add a 3 mil long to accomplish more on the legs and arms, as you might loose some mobility.
What about
"...scorn of my diving buddies?" Two choices:
I. Pity them for not recognizing the creativity; or
II. Blame it "some crazy Texan who convinced you it'd work."
SueMermaid once bubbled...
Yecch. I get all oogey thinking about it, but you can if you want, nobody's gonna laugh at you. Much.
When you wear a 7 mil, you have 7 mm on your arms and shoulders and legs, and 14 mm on your torso. If you doubled up as I understand it, you'd have 8 mil on arms and legs and 17 on your torso. Might not be too bad, really, and layering might actually add an extra point of insulation. Any more than that, though, and you won't be able to bend your arms and legs. Try it out. It makes me tired just thinking about wrestling with that much neoprene.
I have visions of Ralphie's little brother in that Christmas movie, when his mother dresses him so warmly that he can't get up when the town bully knocks him down.
5615mike once bubbled...
I don't follow your math. If you combine a 5mm and 3mm you get.......well 8.
Since when do 7mm suits have 14mm on the torso? What brand of wetsuit is this? Don't know this mfg?!?! LOL
If your wearing 2 jumpsuits as poster indicated, why are you upcharging the torso, actually doubling it.
I think SueM was thinking double FJs, which would really be to much, while you and I were thinking about double Jumpsuits.
Hope I've helped some here, and not talked you to death...
don
