BPW Weighting: Overweight with no Lead

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I don't see the problem. By your own calculations you will be neutral at then end of a dive with no lead using your plate and no wetsuit.

OK, you will be 6 pounds heavy at the beginning of the dive with no ditchable weight. But you still have a wing and a full tank of gas to deal with any problems. You should also be able to swim up 6 pounds without any difficulty. If you feel you need redundant buoyancy, carry a decent sized DSMB. You can also wear a 3mm shorty if you want some neoprene but don't want to worry about overheating. It's easy to let water in if you get hot.
I agree with you. I think I had some bad assumptions and overthought my weighting. From the responses I should be slightly negative once I do a more appropriate weight check and have more realistic numbers for my wetsuit. I have no problems diving without ditchable weight and can easily swim up 6lbs. To much spreadsheet and not enough diving.
 
To much spreadsheet and not enough diving.

That's the spirit :)

I do think that you're very much on the right track here. Your assumptions are within the range of what is safe, now you just need a couple of dives to tune it in
 
Using the wetsuit would be my first choice as it makes the buoyancy a non-issue, and adds protection from jellies and bumps getting back on the boat in sporty conditions.

Worst case, though, I'd put you at -12 lb with a full tank. Compensate +6lb with a larger breath, gently finning for another 6 lb and you're there. I'd first try to put the damaged point of the wing low, though, and restore functionality.
 
Numbers make sense, at least very similar to my experiences as well. I'm a couple inches shorter and a couple pounds heavier, and when I'm in AL backplate and an AL80, I'm putting on like 4-6 pounds of lead. Even in 85 degree water I'm using some type of exposure protection, whether thats a 3mm shorty or a thicker rashguard and some neoprene tech shorts. If I wasn't wearing any neoprene at all, I'd be pretty close to neutral in Aluminum. If I dove with no exposure protection and a HP steel tank, I'm sure I'd be slightly negative too, even at 500psi.

Being slightly negative at the end of the dive when you're doing a safety stop is far better than being slightly positive.

All of the suggestions of double-checking your weight needs at like 15 feet with an empty BC and near-empty tanks are spot-on. Once you're sure of your weight requirements wearing your birthday suit, then figure out how much lead you need to add for any exposure protection options. Don't bring any extra lead than you'll need, and if you're diving without any redundant bouyancy, make sure you're less than 10 pounds negative and you can swim it up with full tanks, compressed neoprene, and an empty wing. I'd also suggest using weight pockets that you can easily empty at the surface if you find yourself with a completely unusable wing.

In that scenario where you're -3 pounds at the surface with no lead and no exposure protection, maybe try a pair of neoprene tech shorts? Having pockets to stash your SMB, spool, and gopro is awfully nice.
 
I may have missed this in the thread, but what size wing are you using with the aluminum plate? Donut or horse shoe shape? Normally a single tank wing will be between 35-40lb weight lift, double tanks will be closer to 60lb lift, so keep that in mind when you use different tank sizes. I use a 60lb donut wing with double AL80s all the way up to double HP120s. On a single AL80 I have a horse shoe 35lb wing.
 
I usually set up for tropical/warm water to be slightly positive or neutral at end of dive. I have no difficulty holding my safety stop, none at all.

Wet suits are nice for protection but a lycra long sleeve and swimsuit or shorts are more than enough for summer diving in the Keys or similar. I hate wetsuits though agreed often are a needed evil but are not always. I can leave the Scuba Steve uniform behind with no regrets.
 
I don't see the problem. By your own calculations you will be neutral at then end of a dive with no lead using your plate and no wetsuit.

OK, you will be 6 pounds heavy at the beginning of the dive with no ditchable weight. But you still have a wing and a full tank of gas to deal with any problems. You should also be able to swim up 6 pounds without any difficulty. If you feel you need redundant buoyancy, carry a decent sized DSMB. You can also wear a 3mm shorty if you want some neoprene but don't want to worry about overheating. It's easy to let water in if you get hot.
I didn't really look at the calculations, but I agree strongly with all of these suggestions - and I dive in south Florida. I always dive with at least a 3 mm suit, although sometimes it is a really old and crushed one and I might leave the back zip open. It is really for abrasion resistance rather than warmth. You should not get too hot with an unzipped shorty, unless you dive shallow in the Gulf of America in the late summer. Water temps can be over 90 there.

An aluminum 100 cuft tank is a horrible pig of a tank! I used to have two of them.

Also: You definitely want to avoid a SS backplate, unless it is a super light one. Aluminum is cheaper and lighter and should last forever. A heavy steel plate would be a really bad choice for you.
 


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