A "balanced rig" and how do you achieve it?

[Okiecaver]

I made the regrettable mistake of tackling this subject on another board without really knowing what I was commenting about. I have heard the buzzwords and been taught to regurgitate them but I kneed to know others opinions as to what it is and how it is achieved.

Here to learn

Dive safe
Brock

 

[MikeS]

Brock,

What do you mean by a "balanced rig"?

Mike

 

[Okiecaver]

that a balanced rig was one that enabled you to be neutral , to "float", at a depth of 10 feet with 500 psi in your back tank(s) and no gas in your bc.

So what would be the procedure for determining/achieving this?

In my case, I dive steel doubles, Faber or PST 95s, ss back plate, argon bottle, etc.

So what do I do to achieve this?

I made a snide comment on another board, thinking I was clever. Instead it descended into name calling and probably ended a couple of friendships;-0

Thanks in advance
Brock

 

[detroit diver]

I would get into a pool with all of the gear you always use, including exposure protection, and dump all your air down to 500 psi. On the surface, add or subtract weight until you sink upon exhale, and rise upon inhale from your reg. This might mean that you need to change BP's. My LP104's are too heavy for a SS BP-I had to change to AL.

 

[ericfine50]

Brock,

I think the AL bp will help. DD is correct, dump to 500 and start taking off weight until you are neutral. Remember the canister light - if you are going from a pro-14 to say a helios, that can affect it as well.

Have a blast. It is fun.

Eric

 

[MikeS]

Okiecaver once bubbled...
that a balanced rig was one that enabled you to be neutral , to "float", at a depth of 10 feet with 500 psi in your back tank(s) and no gas in your bc.

Brock,

What you have described I know as “proper weighting.” You say tomato …

However, I would modify it to being neutral just below the surface (rather than at 10 feet) with a near empty tank (rather than 500 psi). The point is to be able to achieve neutral buoyancy not only on the safety stop but also as you slowly ascend to the surface after the safety stop.

I like to check it in the pool as Detroit Diver described any time I make a major configuration change, and have it worked out for verious configurations of BC and exposure protection. The shallow end of the pool is the best place; if you have any problems, just stand up. And it's convenient to add or take off weights without loosing them.

I also remove any items that I may detach during the dive, i.e. bailout bottle and reel, before the exercise because I may be making a safety stop without them.

Mike

 

[WYDT]

detroit diver once bubbled...
I would get into a pool with all of the gear you always use, including exposure protection, and dump all your air down to 500 psi. On the surface, add or subtract weight until you sink upon exhale, and rise upon inhale from your reg. This might mean that you need to change BP's. My LP104's are too heavy for a SS BP-I had to change to AL.

Ditto! I also have an AL plate for Freshwater with my 104's. I use a steel for salt water and it works out very well.

I would say if you're in the pool to dump the gas to 100psi though... and have a buddy in the water with you! You don't want to be buoyant with empty tanks. That could be ugly if there was a bad problem and you still had deco...

Chances are this will be a mute point as I'm still trying to figure out how to get some more weight off me. Nothing else I can get rid of... may be a good excuse to get that 18W Helios!

 

[Dan Gibson]

Mike,

Try it this way. Put all your exposure protection, fins and mask on and hop in the water. Do not put the rig on. Find out what it takes to just sink you when you exhale. That is how positive your exposure suit, mask and fins are. Repeat this for any combo of exposure protection and write it down.

Now weigh your rig with tanks and full of gas. Use a fish scale. You may have to add weight to get it to sink. Just subtract that off afterwards.

Know what the gas in your tanks weigh. This gives you the positive swing and also tells you what you should theoretically have as ditachable weight.


Now do the math and see what you need to add to you rig to be neutral at your last stop (or surface if you prefer) with no gas left. You will be sharing air in an emergency. This additional weight can be part of the ditchable. You may even find that you can't quite be balanced. A small amount of weight to swim up is acceptable. Many put this at around 10 lbs max. My doubles will put me at 8 lbs negative at the beginning of the dive with air or nirox. Helium improves this slightly. Thats the price for using PST 104s in fresh water. I even use an aluminum backplate.

The above example will get you very close. You may need to add one ot two pounds at best. I mentioned it to a bunch of GUE instructors and instructor candidates in January. Actually, I have to give credit to RJ Myers for showing this to me. We were in a hurry during the March 2002 Fundamentals class at Gilboa. It was a very cold day. This was the quickest way to do it since he already had an idea of what my rig weighed, but not what my exposure protection did for me. I dropped 6 pounds doing this between dives.

 

[Okiecaver]

I have PST 95s and Fabers. The fabers are a bit more bouyant than the Pressed Steels.

Do I do this twice with each set, subtracting the difference, and adding that to the fabers?
or do what I'd really like to do, sell the fabers on Ebay and buy Nanci LaVakes Pressed Steel 95s?

Aside from my cannister, what else comprises ditchable weight?

Dive safe
Brock

 

[ericfine50]

Stages, canister light, video camera - Anything that you could ditch that would allow you to move up in the water if you have a massive wing failure.

Eric