Question regarding trilam drysuit and weighting

[Derelict]

So I dive twin 12L steel tanks with a 300 bar manifold, a steel backplate and hollis f1 fins.

My drysuit is a bare hdc tech dry. My undergarments for 12°c water are a base layer of compression gear, a layer of basic thermals and then a Bare CT200 polarwear extreme thinsulate jumpsuit.

Now with all of this, I've been diving with 9kgs extra for <5m deep shore dives, and 7kg for deeper boat dives.

Does this seem right? I feel as if I'm having to add way too much weight. I usually have my drysuit valve all the way open to allow easy venting, so I'm not sure if I've got too much air in my drysuit.

Is it just because these thinsulate undergarments trap so much extra air?

Anybody with experience using this product, or something similar able to give me an idea?

 

[Storker]

Weighting for a trilam drysuit depends on the undergarments. And undergarments provide insulation primarily by trapping air. So, the thicker the undergarments, the more weight is needed.

Whether you're overweighted or not can only be determined by a proper weight check.

 

[Derelict]

Weighting for a trilam drysuit depends on the undergarments. And undergarments provide insulation primarily by trapping air. So, the thicker the undergarments, the more weight is needed.

Whether you're overweighted or not can only be determined by a proper weight check.

But of course. I've done the above. The weight just seems to be extreme, hence asking if anybody has experience with similar equipment.

 

[Storker]

The weight just seems to be extreme, hence asking if anybody has experience with similar equipment.

My undersuit is a 200gsm Thinsulate thing with a polarfleece lining. I'm diving a single tank BP/W rig with 16# (7.5kg) non-dumpable weight. With a single 10L 300 bar tank - which is pretty negative even when empty - I have 12# + 2kg (7.5) on my belt. In total (dumpable plus non-dumpable weight) that's almost 15kg. I've been told several times that I must be heavily overweighted, but I still do my safety stop with an empty wing and if I don't inflate my suit a little before doffing the rig, I'm uncomfortably shrink-wrapped during the boat ride back to port.

Does this help?

 

[Derelict]

My undersuit is a 200gsm Thinsulate thing with a polarfleece lining. I'm diving a single tank BP/W rig with 16# (7.5kg) non-dumpable weight. With a single 10L 300 bar tank - which is pretty negative even when empty - I have 12# + 2kg (7.5) on my belt. In total (dumpable plus non-dumpable weight) that's almost 15kg. I've been told several times that I must be heavily overweighted, but I still do my safety stop with an empty wing and if I don't inflate my suit a little before doffing the rig, I'm uncomfortably shrink-wrapped during the boat ride back to port.

Does this help?

That helps a lot, cheers! Seems about right then with my gear. I guess it is what it is.

Probably changing undergarments anyway because these ones being single piece restrict my shoulder mobility giving me a hard time reaching my posts.

 

[VR78]

I am diving a very similar combination: same tanks, Santi trilam suit, 4th Element Arctic undersuit, thin wool base layer - with a 2.7 kg steel back plate and 3 kg V-weight. I am neutral at 1 msw with completely empty wing (I do go vertical to dump every little bit in the end of the dive), completely empty suit (nothing coming out with full body rotation), and about 40 bars in the tanks. I think the differences between properly weighted divers are mostly due to the body fat percentage really.

 

[KevinNM]

I dove with the Bare tech dry suit, using the SB base and mid layer. I had a single tank, a SS back plate and 18 pounds of weight when I was properly weighted. Shocked the heck out of a GUE instructor that I needed that much lead. The SB mid layer traps a lot of air.

 

[Neilwood]

I might be wrong but I think weighting for drysuits in particular is very much an individual thing. Two individuals with exactly the same gear will probably want differing amounts of loft in the undersuit therefore two different weightings.

 

[Derelict]

I am diving a very similar combination: same tanks, Santi trilam suit, 4th Element Arctic undersuit, thin wool base layer - with a 2.7 kg steel back plate and 3 kg V-weight. I am neutral at 1 msw with completely empty wing (I do go vertical to dump every little bit in the end of the dive), completely empty suit (nothing coming out with full body rotation), and about 40 bars in the tanks. I think the differences between properly weighted divers are mostly due to the body fat percentage really.

Considering I'm only 68kg with <15% body fat I wouldn't expect it to be an issue for me haha

I'm actually going to look at a set of second hand fourth element attics tomorrow. The two piece should give me more mobility around my shoulders, and less weight required as you said.

 

[KevinNM]

Arctics are great, I just use them with the thin Bare SB base layer.. Xerotherms with a thin base layer are almost as warm.