Need a second (or more) opinion on my buoyancy math

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Because I hate when these threads don't have follow ups, here's my update.

I suspect 25 is to much for the wetsuit since it is a medium. And I am pretty sure 7 for you is way too high. I bet you will drop at least 10 lb from that estimate.

You're probably right but weights on a belt in a tub was the only available option. I did my best to squeeze out any bubbles but at 30' with an overfilled wing I had to surface and drop 6lbs off at the entry point. I definitely could have dropped another four.

I question how you tested boots and gloves. The plastic bag gives more air space. As soon as you start to descend the water will force out a lot of air.

That's an important point that I hadn't accounted for. I managed the air in the bag by poking holes and squeezing out little trapped bubbles. I hadn't thought about saturation after descending a few feet. The same concept applies to the suit and probably more so because of how thick it is.

Are you naturally bouyant? If I were in a lake and you handed me a 7 pound weight there is no way I would float. No even sure that I could float holding my breath. But then I am almost neutral in fresh water.

After the holidays? Probably. :) My wife is pregnant, so no buoyancy from booze but I've definitely packed on some junk food fat. That said, you're absolutely correct. Trying to sink yourself in a bathtub is basically impossible.

Final results: I started with 32lbs (already cut four for the valves), dropped six after the first dip (now does to 26) and bounced off every rock I could find. If there hadn't already been so much silt kicked up, I would have felt like a jerk. I didn't breathe the tanks down enough to be able to do a proper weight check but that's normal for a single dive with sidemount doubles. I should be able to drop another 4-6lbs and still hold my safety stops.
 
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