wetsuit buoyancy concern

[DiverDAD!]

I have recently started diving in cold water (50s) and used a rental wetsuit for my 1st dive. I did OK with the rental suits weight wise, but didn't like it much, so I purchased my own Henderson 7mm Thermoprene farmer john wetsuit and have been having a tough time with figuring out my buoyancy. Most people I spoke with thought it should be about 22-25# buoyant (similar to the rental), so I went with that. I floated like a cork.

I tried adding weight a couple of pounds at a time, but never got to a point where I was properly weighted.

Yesterday, I stuffed the wetsuit, along with my hood, booties and gloves into a mesh bag and weighted it until it was very slightly negative in seawater. It took 36#.

I am 5'6" and weigh 185#, and am a pretty buoyant guy. I'm not as young and strong as I used to be, and it's going to take a lot of weight to make me sink. That's a lot for me to carry around a pitching boat and climb pitching ladders. It is at a point where it's not worth it to me.:depressed:

I'm hesitant to go to a drysuit (would it be less buoyant?) due to a lack of experience. I perceive that they are more difficult to use, and am still inexperienced enough, especially in cold water, to think it might be overload for me.

Is this an unusually buoyant suit?
will it get less buoyant with time (how many dives to 70 ft.?)

Moral support appreciated!

 

[Jorgy]

36 lbs seems excessive.........

Could the items not be fully wet? Or could there have been an air bubble in there some where (boot, glove, top of hood)?

About a drysuit, I am 190 lbs, 5' 10" and dive a hyper compressed neoprene suit (TUSA HRS - no longer available), with a LP95 tank and a 6 lb SS back plate I add 10 lbs of weight with "normal" undergarments and 12 lbs with my "heavy" undergarments (I add a quilted jacket liner and extra set of polypro bottoms).......

Without the benefit if the steel tank and SS BP/W - I guess I would need about 20 - 22 lbs.........in the case of my type of drysuit I think it is less buoyant than a 7 mil farmer john.......

Good question, I look forward to the answers from others........

Hope this helps.....M

 

[sharkbitejeff]

You are now diving with a new suit . It will take more weight to get down until you have your new wetsuit broken in. Then you will be able to dive with less weight. New neoprene is far more bouyant than a used rental suit. I went thru this very same problem with my Bare 7mil arctic. I hope thi helps. Jeff

 

[Interceptor121]

You have more than 50 dives you should not be too concerned about the dry suit, it just takes one dive to get around it and know what to do to avoid a feet first run away ascent.
In terms of buoyancy it is very similar to a 7 mm though I have to say your seems very buoyant but you get out of the water dry which is just great, so if you are planning to dive in cold water invest in a dry suit and that is it!

 

[tstormdiver]

For fresh water, 36 # should be plenty to get you down & then some. In fresh water I only need about 26- 28 lbs. Even in salt water, I would think it may be a few pounds more but not much more than 4-6 # extra. There could be a couple of thing affecting your buoyancy that I can think of off the top of my head. Yes, a new suit may be a bit more buoyant than a well used or worn one, but only by a pound or 2, I would think. Salt water will also affect your buoyancy as salt water is more dense than fresh water. Looking at your profile, it appears that you are a newer diver. One thing I have noticed is that newer divers tend to hold their breath when they first submerge. It is completely sub- conscious & many are not even aware they are doing it until it is pointed out. Holding this air will make you much more buoyant. When you go down make sure you completely empty your lungs,.... almost to the point it hurts. Give it a few seconds & you should start to submerge. If you must take a breath,... do so, but try to get rid of it quickly or you will pop back up. A drysuit is typically MORE buoyant than a wet suit depending a great deal on how much air you use in it & what kind of undergarments you wear under it.

Be aware that in thick wetsuits, once you get to about 10- 15ft of depth, the suit will begin to compress & you must start compensating for it with your BC or you wind up becoming a "dirt dart" to the bottom. The further down you go, the more it will compress & the more negative you will become. It is a little tricky at the first. Give yourself time, it will come. You just have to figure out what works best for you.

 

[GrumpyOldGuy]

I don't know about your specific suit, but I have experienced that new 7mm FJ+J suits are very bouyant when new also, some more than others. I did notice a decrease after 20-30 dives, my sons w/s (XXL) were about 36# new, now about 30#, mine (XL) was 32#, now about 28#, including gloves, boots and hood (5mm). You could be a bit less (I assume size L).

There are lots of ways to manage the weight, even if you need more than 30# there is no reason it should be uncomfortable or beyond your ability. Putting all the weight in an integrated BC makes a very heavy rig. Consider a DUI weight harness to carry the lead, we have 2 in the family and always grab these before the belts if we have a choice. Another option is to split the weight between a belt and the BC. If you have a few extra $$, consider a steel tank (you will need less lead and weight overall) or a bp/w with a S/S plate.

 

[gsk3]

If you're really going to need 36lbs to get down (and you may not...suggestions about air bubbles and new neoprene earlier seemed good), a steel backplate (6lbs usually) with some attached weights would be a good idea, so that you leave 5-10lbs on your belt. 36lbs on a belt is an embolism waiting to happen if it unclips by accident.

 

[redacted]

I measure the buoyancy of all my neoprene and I am not too surprised by your results. One small problem with your measurement technique is you need to do something to release the trapped bubble before you take the measurement. Trapped bubble may "inflate" your results. I measured a friends new, large, unknown brand 7mm FJ and got about 32 lb buoyancy. Your 36 may be just a bit high.

 

[TSandM]

A dry suit may well not solve your problems -- depending on the insulation you end up wearing underneath it, it may require close to the same amount of weight.

But as someone for whom the weight of scuba equipment has posed a major challenge, I have some tips for lowering the overall amount of weight you have to deal with.

First off, make everything you HAVE to take with you as negative as it can be. Most traditional BCs are up to 3 lbs positive, due to the padding. If you switch to something like a backplate system, those 3 lbs disappear. Aluminum 80s are 4 lbs positive when empty; switching to a steel tank (-1 or more when empty) takes five pounds off the total weight you carry. Now we've already gotten that 36 down to 28!

Then, divide the weight, so it's easier to manage. If you can possibly use a weight belt, putting some of the weight there hangs it from your hips instead of your shoulders, and eases the strain on your back and your neck. If you can't use a weight belt because of your body shape, a weight harness will at least keep your weight in a separate "piece" of your gear. I found trying to move a scuba rig with weights in the BC around to be very difficult. To this day, I don't put all the pieces of my setup together until it is on the spot where I will don it.

Cold water diving is always going to be more work than warm water diving . . . it's just life. But with a little creativity, the weight can be made easier to handle, and as you continue to handle it, it gets easier. The man who lifted the calf every day so that, someday, he could lift the whole cow, had the right idea. When I started, I couldn't climb out of a pool with an Al63 on my back. Today, I will be diving double LP85s and a 40 cf deco bottle. Where did the strength come from? Almost all of it from moving scuba gear!

 

[Jorgy]

You make great points.......

My hypothesis is that the OP is diving in temps where the right drysuit would (could) be much less buoyant than a 7 mil FJ........

For the 70 to 50 temp range, a crushed or compressed neoprene drysuit can be used with relatively thin undergarments, for temps over 60 I use a set of military issue polypro and a wicking t-shirt, for temps down to 50 I add a second layer of merino wool long underwear........

The 14 mil of neoprene is simply a lot of buoyancy to overcome.......

My issue is that under about 45 degrees, since the suit is trim cut, I can't fit enough undergarments to stay warm for longer than about 30-40 minutes........so it is not the best for really cold water diving but then I don't really like the ice cream headache and facial numbness.....

But I do the January 1st dive just to get the t-shirt......

Interesting to see if others have the same experience........

M