How much weight to drop

[ystrout]

Hi Everyone,

Since I got back into diving a year ago, all of my dives have been between San Diego and Ventura in cold water. I obviously use a 7mm wetsuit, booties, 5mm gloves, and a hood.

I use 24 pounds of weight locally.

I'm going to Key Largo next week. I'll dump the 7mm wetsuit and probably use a thin Spring Suit that my Dad has had in his garage forever. I think it's a 2mm and is above the elbows and knees. I'll keep using my booties so my fins fit and probably use gloves for protection from the reef/wrecks as well.

About how much weight should I use? I'm doing mainly unguided boat dives.

I'll obviously start slightly heavy and adjust on the second dive of the trip as necessary, but how much should I use on the first dive?

Thanks

 

[Aviyes]

12-14 lbs? I think the rule-of-thumb or starting point is about 2 lbs per mm of wetsuit thickness. The shorty wetsuit might let you get down to 12 lbs.

 

[Johnoly]

... but how much should I use on the first dive?...

I track my weight depending on gear configs. Just my own notes,,,I have a 7 lb difference in a full 7mm with hood and moving down to a 2mm shorty no hood in salt and all other gear configurations being the exact same. Your mileage may vary, but I'd adjust 7 pounds.

 

[scubadada]

Personally, I have a 6 pound difference between a full 3mm and a full 5mm, and another 6 pound difference up to a full 7mm. With an AL 80, I use 8, 14, and 20 lbs.That includes a 5/3mm hooded vest, booties and gloves.

 

[TMHeimer]

With my shorty I use 18 pounds.
Body suit (no thermal protection/rash guard some may call it)--10-12 pounds (can't recall exactly).
7 mil farmer john--42 pounds. Was 37 pounds in my old farmer john, but not with the newer one.
Take extra weight and do a weight check when you get there.
I would use reef (very thin) gloves.

 

[Hoag]

If possible, try to coordinate with your LDS to go to the pool with them when they are doing a pool session. Use the gear that you will be using on your trip and that will give you a very good starting point. Keep in mind that the pool will be fresh water so you will have to add a few pounds to account for the difference between the pool and the Keys (fresh vs salt water), but it will get you close enough that you will be fine tuning on your trip, not sorting out different weights.

 

[CT Sean]

I personally have around 16 lb weight difference for VERY similar exposure protection differences. My wife has a 14 lb difference, again with very similar exposure protection changes.

 

[tursiops]

Much of this information is not very helpful unless you also know the size and weight of the diver, and the newness/oldness of the wetsuit. Using "2 lbs per mm of wetsuit thickness" is a nice rule of thumb, for example, but totally depends on how much wetsuit the person has on. Imagine a very tiny person who has very little wetsuit; changing from 3 to 5mm doesn't add much more buoyancy, whereas a very large person might add a lot of buoyancy going from 3 to 5mm, just because there is more wetsuit needed to cover the larger person. Old wetsuits are thinner and have less buoyancy than new suits of the same nominal thickness. For example, I find going from an old 5mm to a new 5mm, same brand/model, I need to add at least 2 lbs. When someone tells you they use 18 lbs with a shorty, they are also telling you either they like to dive very heavy, or they have an enormous amount of body fat, or maybe both. One person said they add 6 lbs to go from 3 to 5, and another 6 to go from 5 to 7. Good info, but how big are they? That is, how much more buoyancy is being added with the extra 2mm?

If you were to follow the guidance provided by the posts above, you would subtract anywhere from 7 to 24 lbs. Not very helpful.

Your best bets are (1) the pool tests, but don't worry about your total weight, just the weight shift from shortie to 7mm.
Or (2), put the 7mm into a big tub of water and see how much weight it takes to sink it. Do the same with the shortie. If the 7mm takes 16 lbs, and the shortie takes 2 lbs, then 14 lbs is your answer. After all, you and the rest of your equipment are not changing.

 

[Bubbles McGee]

I dive a 2.5mm full wet-suit in tropical water. I used 14 lbs last week in Grenada. I like to have little to no air in my BC and control my buoyancy with my breathing although a may have a tiny bit in at the beginning of a dive. I weigh 215lbs. I would like to drop to 12 lbs on my next trip to see how that goes. Less weight, longer dive. For me anyway.

 

[ystrout]

I'm 6'5 and 200 to 205 pounds depending on how good I ate the night before .

Unfortunately, I won't have time to test all of this in the pool and I currently rent weights and tanks so I can't do the bucked trick.

I guess I'll drop 10 pounds and see where that gets me. If I feel heavy, I'll adjust for the next dive.