New diver, questions regarding weight belts and buoyancy.

[TSandM]

The ScubaPro EveryDry is a neoprene suit. Such suits have drawbacks (like not insulating well in deep water, and being a little harder to manage from a buoyancy standpoint) but for the purpose of your shallow dives, it might do you quite well, and would certainly reduce the amount you need to wear under the suit.

On the other hand, I have a whole crew of friends who routinely ice dive in the Ontario area, wearing laminate dry suits and good quality undergarments. If you are wearing five layers, I suspect you are wearing stuff that wasn't designed for diving. When you do that, you end up with more bulk, more buoyancy, and less efficient insulation than you do if you go for purpose-made garments. If you're looking to upgrade your insulation, rather than buy a new suit, I'd invest in a really good diving undergarment.

 

[rmh84]

Personally, I'm not a fan of intigrated weights, I don't find them to be more comforable, or a convenience in any way, but I know I'm a bit of an odd man out in this regard.

The metal BP/W idea is a good one - but in the meantime if you don't want to go crazy on the new equipment I got a neoprene weight belt on Ebay for about $15 that is super comfortable. I imagine it would add a tiny bit more bouyancy being neoprene, but I have not noticed any change in my weighting based on this.

 

[xSandman3]

Maybe I missed it, but are you diving hookah or scuba? If on scuba, are you using aluminum tanks? If so, you have a huge buoyancy shift as you breathe through the air in the tank. For 15 foot freshwater diving, it would be tough to overcome this using aluminum. Try a steel tank and see if that helps.

 

[fisheater]

Maybe I missed it, but are you diving hookah or scuba? If on scuba, are you using aluminum tanks? If so, you have a huge buoyancy shift as you breathe through the air in the tank. For 15 foot freshwater diving, it would be tough to overcome this using aluminum. Try a steel tank and see if that helps.

Aluminum vs. steel doesn't have any effect of buoyancy shift. Total buoyancy, yes. Shift, no.

The shift is due to the amount of air consumed. A larger capacity steel tank will have a larger buoyancy shift than a lesser capacity aluminum tank. And visa-versa.

 

[redacted]

Maybe I missed it, but are you diving hookah or scuba? If on scuba, are you using aluminum tanks? If so, you have a huge buoyancy shift as you breathe through the air in the tank. For 15 foot freshwater diving, it would be tough to overcome this using aluminum. Try a steel tank and see if that helps.

Isn't the buoyancy shift the same dependent only on the amount of gas?

I noticed the under ice gold prospectors in Alaska seem to favor wet suits with warm water circulated through them. But that might just increase your weight requirements.

 

[dumpsterDiver]

I think you will want to wear some pretty large ankle weights. Are you wearing fins or boots? For some commercial diving I have done, a pair of very large rubber snow boots over outside of exposure protection suit adds some warmth, allows bulky footwear underneath, protects the suit and also makes wearing ankle weights more comfortable. You can make your won ankle weights with bike inner tube filled with lead shot and a heavy line through the center and connect with fastex plastic clips. Seal off the end of the innertube sections with string and a constrictor knot and then cover the whole creating with duct tape. They will withstand years of abuse and you just have to periodically remove some old duct tape and add a new layer. for working face down, you may want to add some lead to the front of the harness on the chest. For a heavy working weightbelt, I used to get a rubber or plastic mud flap from a tractor trailer (find them lost on the hiway if you look) and then cut a wide strip of maybe 8 inches and use this as a pad in the back of the weightbelt to better distribute the weight across the lower back. I preferred heavy hip weights, maybe 12-14 lbs each. In addition, you are going to want to wear some non ditchable lead on the harness in whatever locations will work. If wearing a tank, you may want to hang some additional ankle weigts from the valve neck to assist in keeping a head down working configuration.

 

[windapp]

Isn't the buoyancy shift the same dependent only on the amount of gas?

I noticed the under ice gold prospectors in Alaska seem to favor wet suits with warm water circulated through them. But that might just increase your weight requirements.

If you look at the problem closely, it becomes obvious that there is a problem with trim shift. If the tank extends past the bottom of the BCD, and the air in the BCD is used to compensate the air in the entire length of the tank, your center of mass will start out back, and work its way forward as the tank gets lighter, and the BCD gets emptier.