Do thin warm undergarments exist?

[RandomGuy1]

I currently dive a fusion and I use two different undergarments depending on the dive. For dives in 60 degree and warmer water I have been using a base layer of icebreakers merino wool and this Immersion research k2 union suit over top. In this combo I have no dexterity issues. My issue is when I switch to my much warmer fusion thermal suit, which also happens to be much bulkier. I can't seem to reach my valves very well, reaching across my body to the dump valve is a chore. With that said, I love the warmth of the fusion thermal, but would like something a little less bulky. Suggestions?

 

[207diver]

I dive a forth element Arctic it is very warm and not very bulky.

 

[Jack Hammer]

There are a few. 4th Element Arctics are nice and the Santi BZ200 is nice (I own both). I primary use my Santi undergarments as I prefer the way they fit me.

Another thing to consider is suit positioning when you get in the water. I adjust the arms as I get in the water so when the suit "shrink wraps" onto me ill have better mobility. I also stretch out just below the surface before I descend for the same reason.

 

[Jonn]

Thin but warm? Electric heat. Motorcycle gear tends to be cheaper then scuba-specific stuff.

 

[lermontov]

try merino wool from outdoorsy type place

 

[Storker]

It's tricky to have good insulation and little bulk, as the medium which insulates is air. Less bulk = less air = less insulation. There is some variation, but generally warmer = more bulk.

Thin but warm? Electric heat. Motorcycle gear tends to be cheaper then scuba-specific stuff.

Can you turn on and off a heated motorcycle vest without opening the suit? YMMV, but I would never wear an electrically heated garment that couldn't be disconnected without opening my suit. That could be nasty...

 

[ajduplessis]

You have to adjust your harness (shoulders, waist and crotch) when using thicker thermals. For this reason alone I use the halcyon cinch on my plate.

 

[tbone1004]

It's tricky to have good insulation and little bulk, as the medium which insulates is air. Less bulk = less air = less insulation. There is some variation, but generally warmer = more bulk.


Can you turn on and off a heated motorcycle vest without opening the suit? YMMV, but I would never wear an electrically heated garment that couldn't be disconnected without opening my suit. That could be nasty...

Textile engineer, and currently actively working on some heated vest development but have also done some work professionally with passive thermal garments.

Yes to being able to cycle power on a motorcycle vest, scuba heated garments are not any different than their motorcycle counterparts as long as said motorcycle vest has some sort of barrel type power connection. That goes through a bulkhead of somesort and you can turn on and off via the battery pack or heat controller etc. Before companies starting producing scuba heated vests people just bought motorcycle vests and used them. With the exception of those made by Exo2, they are all just woven carbon fiber panels. If you want a durable much higher quality product, buy the Exo2 vests. MUCH better design because they can't short.

Thin and warm doesn't exist for passive insulation unfortunately. Air needs to be used as the buffer, and to have air you have to have something to keep the suit away from your skin necessitating thicker undergarments. Some fibers work better than others, and wool is by far the best insulating fiber on the planet. Some wools better than others, and Merino is one of the better available commercial fibers. Qiviut is actually the best, but you don't want to see the price of Musk Ox wool.... It's terrifying *read you can buy UWLD 160wh canister, with heat controller, with a heated vest, AND the new snazzy double swivel bulkhead for your drysuit for the cost of union suit made out of this stuff*.

You can also try diving with some more air in your suit with the lighter undergarments to see if that helps, but realistically if you want to stay with thin undergarments and stay warm you have to go to active heating. Chemical heating is super dangerous so don't use hand warmers, and electric heating isn't that expensive.

 

[Storker]

Some fibers work better than others, and wool is by far the best insulating fiber on the planet.

I've been claiming this over and over again, ad nauseam. I'm sure there are people here who are fed up with my rantings about how superior wool is compared to other fibers, particularly if there's going to be some moisture/condensation and the garment is inside a waterproof barrier which hinders diffusion of water vapor away from your body. IOW exactly the conditions you find inside a drysuit...

Whatever my thermal layer is, I always wear a wool wicking layer.

 

[tbone1004]

also remember that wool is slightly exothermic when it gets wet, so it gives off a little bit of heat...