How accurate do you guys find DiveBuddy.com for their weight calculator?

[Justin Phillips]

I did my first fresh water dive this weekend and I went to Dive Buddy and put in my weight, my tank and the fact I was wearing a 2 piece 7mm wetsuit and chose novice. It gave me 32lb's as my weight. During the dive I started my decent and found I went down 2ft and that was as deep I was going no matter how much air I exhaled. Next dive I am going to try 38lbs but I guess is there a good source for starting weight.

I will be moving back to Salt next month but with a new config, lost weight etc. and I dont want to get on a dive boat and be weighted wrong, or under weighted.

 

[James79]

This thread is what you want:

Info - Optimal Buoyancy Computer

The Optimal Buoyancy Computer A tool to help nail buoyancy and improve safety, before you splash 1) How much lead should I carry with my new wetsuit? 2) How big a wing should I buy? 3) Will my BCD support my lead, both at the surface and when my wetsuit is compressed at depth? 4) Will my BCD...

scubaboard.com

Once you get your details nailed down, it will spit out pretty darn good answers for configuration changes.

Respectfully,

James

 

[grantctobin]

I’d use the one on this forum. That said, I’d also encourage listing your current gear config and go from there. There are a significant number of variables, many of which the SB calculator addresses. 32lb is a large chunk of weight.

 

[CycleCat]

It recommended I be WAY overweighted. I use half of what it computed.

 

[inquis]

I use about half of what Dive Buddy recommended, even with a jacket BCD. The SB calculator, OTOH, gives sensible answers, and you will learn a lot as you use it.

 

[covediver]

A rule of thumb back in the day in Socal saltwater diving with a two piece 1/4 inch (about 7 mm) was 10 pecent of your body weight plus 2 to 4 pounds to start. Not sure what the fresh water reduction would be.

 

[Altamira]

Dive Buddy works well for me. I know others feel it is not accurate for their body and gear configuration, and that indicates a wide range of weighting requirements. I have also used the Optimal Buoyancy Computer, and find it pretty close to what I use, and what Dive Buddy recommends for me. I dive about two pounds over perfect weighting because I see no real downside for the type of rec diving I do, and don't want to have to struggle to stay at safety stop in the event I get to the safety stop with less air than planned.

 

[boulderjohn]

I found Dive Buddy recommended about twice as much weight as I need in a variety of configurations.

 

[boulderjohn]

Years ago I worked with a dive shop that did OW checkout dives in fresh water with old-style, bulky, 2-piece 7mm suits. I am pretty sure none of our students ever needed 32 pounds.

 

[Justin Phillips]

I am 287 lbs, wearing a very bulky 2 piece 7mm from Neosport (this seems to be the problem, when this is not on I can go down without a wetsuit with less than 15 lbs in fresh water, Sherwood Avid Phantom. I have 2 scuba pro 109s, and a mk25. My front had 26 in the front removable pouches. and 6 in the back trim pouches, let all the air out of my BCD using the dump valve and would go down 1-2 feet and stop. Exhale everything and go nowhere. I am positive all the air was out of my bcd and I used the dump valve to make sure. I only seem to be a 1 or 2 lbs off I need to get to a point like 6ft where my suit will start to compress.

Now when I was 30 lbs lighter (in my weight) I needed 38 lbs in a bulky 2 piece 7mm to get down in salt water, 34 was not enough as I have notes in my dive log that said dont dive with 34 again its not enough but that was for salt. Either way I found a dive club that is going to get to a dive early with me this weekend and work on my weighting before the dive. That way I can get it perfect.

I am dieting and losing a few pounds a week and working to get back down to 25 but for now I weight what I weigh, I have a lot of muscle mass which is not boyant so I am not sure what is going on. This is my first dive will 100% new gear so I will dive a few more times and get the bugs worked out. I will work through the excel document.