Drysuit weighting

[rickc]

Had my first pool session last night, and woud like some advice on weighting. My instructor was not very helpful, perhaps one of you experienced drysuit divers can help?

I normally use 20 lbs with a full 7MM wetsuit rig (hood, gloves, etc.). Last night, in fresh water, I tried 28 lbs - no hood, no gloves. At the surface of the pool, doing a bouyancy check, I sunk a little below eye level, maybe the top of my head. But, I had problems submerging and had to kick down. At the bottom of the pool (10' ft) I had problems controlling my bouyancy.

What weight should I try for my first ocean drysuit dive? I will have both hood and gloves. It is also a beach dive, so, the less weight I have to carry on my poor old body, the better.

TNX for any advice.

 

[Arduous]

Hi rickc:

It is difficult for someone else to tell you how much weight to use for your dive. It’s one of those things you have to figure out through trial and error. It depends on your body composition and the type of insulation your using. As well as the type of dry suit you’re diving in. Funny the weight difference you mentioned 20 for wet 28 for dry. I have the same weight differential. I use 16lbs in my 7mm wet suit and 24lbs in my Trilaminate dry suit. 8 pounds difference just like you. Something to take note of, you should make sure your dry suit has been vented of all air and your BC is empty as well. If you have air in your BC or dry suit, you will find it hard to submerge at the start of your dive. It’s good that your planning a shore dive. You can take some extra weights with you and fine tune yourself before actually making the dive.

………………………..Arduous

 

[SubMariner]

The best way to see how much weight you will need is to do a buoyancy check EVERY time you change:

1) undergarments.

2) type of water (fresh vs. salt).

Both of these will affect how much weight you need to have in order to be neutrally buoyant.

Reminder: to do a buoyancy check, put on ALL the exposure protection you will be using PLUS your BCD. With a lungful of air you should be able to float at eye level; when you exhale you should sink. If you have to kick to get down after you have exhaled, you do not have enough weight.

Don't forget if you are diving with AL tanks to add about 3 pounds to compensate for the positive buoyancy of a near-empty tank (1000 psi).

Don't get hung up on how much weight you will be using. As with any new weighting situation, this will change with time. BTW, I found it helpful to note weighting in my logbook for different dives. That way I had a point of reference & didn't have to keep doing buoyancy checks. It also means you can be better prepared by having a weight belt already set up for salt vs fresh, etc.

Hope this helped,

~SubMariner~

 

[MXGratefulDiver]

You'll typically have to add a little weight when switching from a wetsuit to a drysuit ... how much depends on both the type of drysuit you purchased, and the type of undergarment you're wearing. A compressed neoprene suit will require more weight than a trilam, if you wear the same undergarment in both. However, because of the added warmth of a neoprene suit, most folks wear less undergarment, so it's a tradeoff.

The fit of the suit also makes a difference ... because a poor-fitting suit will not put the air where you need it, and you'll discover that you have to overweight in order to achieve proper trim.

As the previous poster suggested, every time you make a change, perform another weight check.

Also, keep in mind that to some degree you're relearning buoyancy skills going from a wetsuit to a drysuit. After a few dives, you'll be able to start dropping weight again as the feel of the suit becomes more natural and you relax more.

... Bob (Grateful Diver)