Still trying to balance my rig...suggestions?

[victorzamora]

I agree that maybe an Alu plate would help. First thing I'd do is get that HP100 down to ~500PSI and try holding a safety stop at 15ft. If you're still negative with no lead. If you get an alu plate, I'd recommend doing the same thing. If you're STILL negative at 15ft then I don't know what to tell you.

 

[Eric Sedletzky]

I agree that maybe an Alu plate would help. First thing I'd do is get that HP100 down to ~500PSI and try holding a safety stop at 15ft. If you're still negative with no lead. If you get an alu plate, I'd recommend doing the same thing. If you're STILL negative at 15ft then I don't know what to tell you.

Well, if he was still negative at 15' with a steel 100 and an aluminum plate then he'd either have to switch to a poodle jacket or an AL80, or both

 

[eelnoraa]

That is exactly the point I am making, not only can I not float a the surface with an empty wing (I immediately sink like a rock unless finning very hard), but even w my 25lb wing fully inflated, I have to moderately fin to keep head above water at the surface.

This sounds like something is very wrong. Better to have an experienced local diver to take a look. If what your said is indeed true (which I doubt), you are diving 25lb over weighted with 5mm wetsuit. Swapping to lighter plate or AL80 aren't going to solve your problem. Again, have someone look at it.

The "Wetsuit don't go well with steel tank" argument is about having ditchable with because of wetsuit compression at depth lossing buoyancy. But before thinking about ditching vs non ditching, you need to first figure out your overall weight first.

---------- Post added September 13th, 2013 at 11:39 AM ----------

Why are you wanting to be able to swim up a steel tank?
If you're worried about BC failure, the much easier solution would be to just carry a lift bag with you or always dive with a buddy.

The whole point of the BC is to keep you neutral when you're negative. If it fails, and you have nothing you can ditch you need to come up with a 2nd source of lift. Either a BC with dual redundant bladders, or a lift bag, or grab onto your buddy and do a controlled ascent.

In one of my cave classes, we had to "retrieve our unconscious instructor" from the bottom of a spring. While this may not sound like much of an issue, she had dual steel LP108's and a stage bottle on. I had dual steel LP85's on I could not lift her at ALL with just my own BC. My buddy came over to assist and we finally got her top side.

When we surfaced, she said we could have done one of two things:
1 - used HER BC for inflation, as it was more important to get her out of the water than let her drown, if she got away from us due to being too positive, it was better to deal with an embolism or DCS than to be dead.
2 - Drop her tanks and put her on my back gas.

Reason for mentioning this is... unless you're diving solo. this is what a buddy is there for. If your BC fails, and all your weight is on your BC/Tank (you have nothing to drop then you should be able to grab a hold of your buddy and the two of you ascend using his BC, or absolute worst case, get on his octo and drop all your gear.

I have to say when I'm diving doubles, I can in no way swim that amount of weight up. But I have a buddy or a lift bag to assist should I need it.

---------- Post added September 12th, 2013 at 09:00 AM ----------



Steel tanks are perfect for wetsuits IMO. You just have to get used to their extra weight characteristics.
Myself and all my buddies (all cave, tech, etc) prefer steel to aluminum any day. We all dive in various thickness wetsuits, some in drysuits.
My first tank I bought a few dives after OW was a steel LP108. I dove the heck out of it. Never once having any issues with any kind of buoyancy, trim, etc.

You just need more time in the water, more practice. Your profile says you have less than 50dives... just spend more time with your gear, your tank, etc. Spend a LOT of time (or a dive or two) in very shallow water...im talking 10-20ft. Spent time traveling between those depths, hitting that magical 15ft make of "impossible buoyancy" many people have a hard time with. This will help make you a rock solid diver. Plus at that depth, a 100CuFt tank should last you a LONNNGGG time.

Don't write that tank off yet... any good diver should be able to dive with ANY tank and not have it effect his trim or buoyancy. It just takes practice to get it right. Don't be discouraged any tank is not a wasted purchase..it just becomes another part of your stable later on

My head also exploded. I think we are definitely trained very very fundamentally different.

 

[DiveDaddyDale]

It's been a while since I posted my response to the great suggestions here.
I have carefully calculated my rig weight as follows;
BCD w steel plate, regulators, fins, lights (2), harness, computer, compass, 5mm full suit, 7mm boots, knife, smb and bottom timer, AL 80 or HP100= 52lbs out of water (dry).

My bp/w and harness weighs in at 12lb. Add OMS Splitstreams and mask and I am near 58lbs dry weight.

I have concluded that switching to an AL plate would reduce my overall weight by only 4lbs, not sure that will really help me out that much. I have looked closely at the Halcyon Infinity with an AL plate which weighs 9lbs according to Halcyon rep. That would only be a reduction of 3lbs...not enough.

Am I wrong or is it true that many divers using Tobins steel plate in combination with a HP100 need to ADD weight and, those working with a AL plate need to add even more weight (wearing the SE exposure protection, (5mm full suit).

Definately missing something important here.

 

[Eric Sedletzky]

It's been a while since I posted my response to the great suggestions here.
I have carefully calculated my rig weight as follows;
BCD w steel plate, regulators, fins, lights (2), harness, computer, compass, 5mm full suit, 7mm boots, knife, smb and bottom timer, AL 80 or HP100= 52lbs out of water (dry).

My bp/w and harness weighs in at 12lb. Add OMS Splitstreams and mask and I am near 58lbs dry weight.

I have concluded that switching to an AL plate would reduce my overall weight by only 4lbs, not sure that will really help me out that much. I have looked closely at the Halcyon Infinity with an AL plate which weighs 9lbs according to Halcyon rep. That would only be a reduction of 3lbs...not enough.

Am I wrong or is it true that many divers using Tobins steel plate in combination with a HP100 need to ADD weight and, those working with a AL plate need to add even more weight (wearing the SE exposure protection, (5mm full suit).

Definately missing something important here.

Dry weight and in-water weight are two entirely different things.
Your rig might weigh 12 lbs out of the water but in the water only the metal components are negative. So in the water a 6 lb plate and other metal components are the only thing that counts and even then they will be slightly lighter than on land because water is heavier and denser than air.
The plastic or composite components like the webbing and wing are technically lighter than the water.
Your wetsuit has dry land weight but underwater it requires a weightbelt to offset.
Tobins steel plate isn't any different from any other 6 lb plate, and any aluminum plate will be 3 lbs.,.. or whatever they are...

If you use an aluminum plate and and an AL80 with your 5 mil I don't see why that wouldn't work.
A steel tank is going to be slightly negative or neutral when empty underwater (depending on the tank).
A standard 80 aluminum tank (not a neutrally buoyant AL tank) will be about 3 lbs. positive in the water empty.
Yet the aluminum tank on land will be a few lbs heavier than a steel tank that is about the same size on land.
I have a wetsuit that is 1/2" thick (seriously). On land the thing weighs probably 45 lbs. But underwater it requires a 35 lb weighbelt to offset plus the weight of a plate and a steel tank, and I'm slightly light!

So dry land weight means nothing when you try and apply the logic to underwater weighting.

 

[bakodiver391]

This sounds like something is very wrong. Better to have an experienced local diver to take a look. If what your said is indeed true (which I doubt), you are diving 25lb over weighted with 5mm wetsuit. Swapping to lighter plate or AL80 aren't going to solve your problem. Again, have someone look at it.

The "Wetsuit don't go well with steel tank" argument is about having ditchable with because of wetsuit compression at depth lossing buoyancy. But before thinking about ditching vs non ditching, you need to first figure out your overall weight first.

---------- Post added September 13th, 2013 at 11:39 AM ----------



My head also exploded. I think we are definitely trained very very fundamentally different.

That's as may be, but remember that your training is just one instructor's take on the whole diving equation, there are many more. I practically live in steel doubles and a wetsuit during the summer months and I am perfectly happy with this rig because it is the best tool for the job I have to perform. Al doubles do not have the gas volume, buoyancy characteristics, or fore and aft trim characteristics that I require, and with 4 different bladders to assure that I can remain neutral, all the arguments about swimming the rig up are specious. I'd like to see anyone hold depth for an hour deco hang while swimming. To the instructors out there, you should explain both the pros and cons of both philosophies, and let the student try both. To do otherwise is to do a disservice to your students.

 

[Glenn08]

I use twin 50's, Selpak manifold, valves down. (My rig looks like I copied Akimbo). I felt off-balance, so I added a piece of 4 inch PVC pipe with closed ends - a buoyancy tank. Now my rig is almost neutral. I had to add lead to my weight belt to compensate, but I am much more comfortable now. If you are adding air to your BC to compensate for your tank, it will compress or expand with changes in depth. My buoyancy tank doesn't vary with depth. You need to ponder how your rig behaves in the water, and decide whether you need to adjust your lead, or something else.

 

[John C. Ratliff]

Try one of our rubber weightbelts...

View attachment 165352

I'm not sure if this has been addressed, as I have yet to read this entire thread, but there is no quick release on this belt. This type of buckle has been a no-no since the 1950s.

SeaRat

---------- Post added September 27th, 2013 at 06:40 PM ----------

I agree with the direction you're going - like you, my personal floor for non-ditchable weight is defined around what I can swim up.

I found my limits from the other direction, so to speak. I tried swimming up various size weight belts and found that:

I can swim up 10 lbs easily.
I can swim up 20 lbs, albiet with a whopping RMV.
I can swim up 30 lbs in little 10' "sprints" at a time, with rests in between.
I cannot swim up 40 lbs.

I teach little tune-up sessions for a local dive club during the winter, and found that physical conditioning, fining technique, (and especially!) fin selection plays a huge part in this. Split fin users, for example, seem to top out at 15 lbs no matter how good of a shape the diver is in.

So you might consider changing your fins, if that's the problem. That way you can preserve the great trim you get from a SS plate/HP 100.

If not, I'd look at a plastic plate, like the Kydex plate from DSS. This way you can add the same weight as an aluminum plate to weight pockets on the upper cam band, which may keep you in trim when wearing a small weight belt.

Since this is the Advanced forum, you might consider adding a tail pouch and carrying a lift bag as redundant buoyancy. Get lessons from a technical instructor first, as this is something oft seen in technical diving, and they will be well suited to pass on the advantages (and disadvantages) of this technique, as well as the little things that will keep you safe.


All the best, James


All the best, James

James, I'm curious how long you can stay on the surface finning being 10 pounds overweight? Thirty minutes? An hour? My point is that we used to teach that a diver started out neutrally buoyant at the beginning of a dive (full breath, floating at eye level without finning). Granted, this was before we had BCs, but it works pretty well. Now, apparently people have become totally dependent on their BC to be neutral at the surface after a dive. This doesn't make sense to me as a vintage diver (granted, I have not been tech diving, but why be this negative at the surface?).

SeaRat

 

[victorzamora]

John, neutral is considered half breath floating at eye level with an empty tank

Sent from my SCH-I545 using Tapatalk 4

 

[Jim Lapenta]

I'm not sure if this has been addressed, as I have yet to read this entire thread, but there is no quick release on this belt. This type of buckle has been a no-no since the 1950s.


SeaRat

You obviously have not used or seen a MAKO belt. This buckle releases faster than my web belts and does not get hung up. I bought one for my GF because it is a safer alternative for her. Web belts are difficult for her to manage and the buckles are questionable at best as far as releasing compared to the MAKO. This type belt has been used by freedivers and spearfishermen for years. Maybe you are thinking of the old more or less home made versions that took a surplus buckle and put it on a piece of rubber with a slot for the pin.

The way the MAKO belt is set up the pin does not come thru a slot but a hole at such an angle that it is damn near impossible to get it snagged unless it has been damaged in some way. I am going to be adding one to my own gear this week after seeing how well my GF's works and how much she loves it.

I do not sell or work for MAKO in case anyone wonders. I just believe that if a product is good and increases safety you back the hell out of it no matter who makes it or sells it.