Lift Question

[ams511]

Although I an not new to scuba diving, I have only recently started diving again now that I live in Pa. My normal configuration is an Al 80 tank, a 7 mil 2 piece farmer john wetsuit, 24 lbs lead, and a Beuchat BC rated at 42lbs lift. I noticed that I have trouble getting down. In other words I can't do a feet first decent, but once at depth (90 ft) the BC is unable to provide enough lift to keep me off the bottom. I need to swim up to about 40 feet or so before it is able to do so. I figure the compression of the wetsuit must be the cause and due to my difficuties submerging I don't think I am overweighted and I do float at eye level at the surface with no air in the bc. Any suggestions as to how to correct the problem? I am thinking that maybe switching to a 1 piece 7 mil suit might help the problem being the compression should be less. However quarries do get cold. lol

 

[Kim]

Although I don't dive cold water like you from what you are describing I think I'd be looking at drysuits! I'm sure someone with experience will comment though!

 

[Geddes]

OT: Where in PA are you?

 

[neil]

Ams,
How much do you weigh? What size suit do you wear? I weigh 230 and use a bit more lead than you do with a BC with about 45 lbs of lift. AND a steel tank. I have no trouble getting neutral at that depth. Of course that's in sea water. Are you waiting until you get to 90 ft to try and get neutral? That'll bounce you off the bottom if you're not quick enough. You need to STAY neutral or only slightly negative on the way down and keep adjusting.

Neil

 

[DandyDon]

I'd be afraid of a BC that can't handle 24# of lead. I've seen some, but I wouldn't dive them.

 

[ChrisA]

Although I an not new to scuba diving, I have only recently started diving again now that I live in Pa. My normal configuration is an Al 80 tank, a 7 mil 2 piece farmer john wetsuit, 24 lbs lead, and a Beuchat BC rated at 42lbs lift. I noticed that I have trouble getting down. In other words I can't do a feet first decent, but once at depth (90 ft) the BC is unable to provide enough lift to keep me off the bottom. I need to swim up to about 40 feet or so before it is able to do so. I figure the compression of the wetsuit must be the cause and due to my difficuties submerging I don't think I am overweighted and I do float at eye level at the surface with no air in the bc. Any suggestions as to how to correct the problem? I am thinking that maybe switching to a 1 piece 7 mil suit might help the problem being the compression should be less. However quarries do get cold. lol

The problem might be that you don't really have ALL the
air out of the BC when you do the weight check and then maybe you over weight to compensate. Taking air down with you in your BC would have the same effect as using a _very_ thick suit

24 pounds sounds like very little weight to me but then I dive in
saltwater you in fresh.

 

[CrazyDave]

I dive a Henderson 7/5 hyperstretch with a Sherwood Avid B.C. I take 22lbs with me and I have been losing about a pound every 10-15 dives or so. I weigh 250 6'. If you are doing your check at the surface correctly you should not be having those problems at depth. You should have plenty of lift to keep you off the bottom. It does sound like you have air in your B.C when you do your checks or that Farmer John is trapping air when you drop down. As far as the feet first problem, maybe shift your tank a little lower on your back, or maybe your weights are riding a little high. Is that BC intergrated or do you wear a belt? I had to shift my tank lower to stop that problem myself. Once I found the "SPOT" I have not had that problem again.
Good luck.

 

[ams511]

Thanks for all the comments. The answers to your questions are as follows: I am 5'9"
180lbs (could stand to loose about another 10-15 lbs) and wear a large size wet suit. The BC is non weight integrated (they didn't sell em back when I bought it), Beuchats are not widely known but quality dive gear. The BC does have dump valves at both the top and bottom. I live in State College. In salt water with no wet suit I take about 14-16 lbs (I used to live in Florida). I do try to dump all the air, although as you all know air may be trapped either in the wetsuit or a bc. Thats why I am thinking more of a single thickness suit. I thought about a dry suit but the cost is too high at the moment and I am not really a year round diver. The 90 ft dive occured during my AOW course and the instructor did watch the buoyancy check on the surface so I am sure it was done correctly. Although, next time I do it I will make sure not to inflate it before I enter the water and work out all the air on it on the surface. It is a weird problem which I guess only I have, so maybe it is not equipment related but user related.

 

[Starfish]

Thanks for all the comments. The answers to your questions are as follows: I am 5'9"
180lbs (could stand to loose about another 10-15 lbs) and wear a large size wet suit. The BC is non weight integrated (they didn't sell em back when I bought it), Beuchats are not widely known but quality dive gear. The BC does have dump valves at both the top and bottom. I live in State College. In salt water with no wet suit I take about 14-16 lbs (I used to live in Florida). I do try to dump all the air, although as you all know air may be trapped either in the wetsuit or a bc. Thats why I am thinking more of a single thickness suit. I thought about a dry suit but the cost is too high at the moment and I am not really a year round diver. The 90 ft dive occured during my AOW course and the instructor did watch the buoyancy check on the surface so I am sure it was done correctly. Although, next time I do it I will make sure not to inflate it before I enter the water and work out all the air on it on the surface. It is a weird problem which I guess only I have, so maybe it is not equipment related but user related.

Have you tried moving your weight around. I found that placement of the weight had an effect on how easy it is to do a feet first decent. --Starfish