How to set up first set of doubles?

[cerich]

Where you are at regarding gear and the future of your diving is unfortunatly also where you start to run into the very strong views of tech divers.

I guess the reason we jumped from the question to training is because the very nature of the question shows that you are early into the process of the transition to tech. No matter how poorly we may word it having been there ourselves we want you to avoid costly (money and safety) mistakes. Of course we would also like to convert another to our way of thinking while at it!

My way of diving now even a 55lb wing would be fine in the great lakes, other ways you'll need more lift(I once dove and taught that way in the great lakes).

Sorry if we came off like preachers

Best,

Chris

 

[jonnythan]

94 is really, really, really huge. I have a 55lb wing and wish I had a 45lb wing.. and I dive in freezing waters with big steel tanks. I'll never need more than 55lb of lift.

Anyway, 1 SPG is all you need... now find an instructor!

 

[DTB1981]

In short the one SPG goes on the left post.

Your prime reg and wing inflation goes on the right post.
Secondary reg and secondary inflation go on the left. Secondary inflation can be your dry suit and or your second power inflator if you are on a double bladder wing.

You leave the isolator open so you are breathing from both tanks. If your SPG dose not go down you know the isolator is closed. If you have problems with the left post reg and shut it off you will lose your SPG too but this wont matter to much because the dive is over.

 

[DTB1981]

How is a 94 too large? Once I become more advanced i'll need all the lift I can get. If it doesn't get utilized to its full potential what's the harm?

A 94 is for large LP double steel tanks and extra stages. A 40lbs wing will support double 80's and a stage bottle with no problems. You want to try and use only what you need, a 94 wing will trap air and make your trim and buoyancy vary difficult to maintain. This is critical once you become more advanced and have to maintain deco stops with a high mix stage.

I am not saying you can not use it to dive you double 80's. Just it is not the best choice, and will make diving more difficult than if you use the right size wing.

 

[wreckchick]

The reason I'm hammering training is because by the very nature of your questions it appears that you're not currently diving with anyone who's using the configuration that you're trying to set up. At this stage of your diving it's critically important to be able to consult with someone that has more experience than you in the type of diving you're contemplating.

I apologize if this sounds harsh, but the world you want to enter is unforgiving.

R

 

[cyklon_300]

Once I become more advanced i'll need all the lift I can get.

This statement is confusing...what you need is the CORRECT amount of lift for your configuration (cylinders, backplate, wing, suit, tools, stages, etc.)...

Almost everyone that has posted is in agreement that a 94-lb wing is a blimp for what you've described. What's the resistance to hearing good, free advice?

I use a 55-lb wing for steel 104s and double stages for comparison.

 

[cool_hardware52]

Wing lift is a function primarily of the buoyancy of your exposure suit.

A wing needs to do two things: Float your rig without you in it, and compensate for the loss, or potential loss of buoyancy of your exposure suit.

I'm pretty sure a set of AL 80's + BP + bands , manifold, regs harness etc doesn't weigh 94 lbs in the water. Do a little homework, look at some tank buoyancy specs and you can figure it out. I'd guess more like ~ 25-30 lbs for the rig.

How buoyant is your exposure suit? I'm assuming a DS, based on the location. Get in the pool in just your undergarment and DS, with minimum gas in the suit. Add lead until you are neutral. This varies, but is typically in the 20-30 lbs range, maybe 35 lbs for thick undies on big guy.

This weight represents the max you can loose in a total flood.

In doubles you will need to be overweighted at the start of the dive by the weight of the gas you will breathe. 160 cuft weighs ~ 12 lbs. This is the absolute max you'd need to be overweighted by.

Let's say your suit is 30 lbs bouyant, and you add 10 lbs for the gas. That's a 40 lbs wing. 40 lbs is plenty to float the rig.

A bigger wing does not make a "more advanced" diver. A huge wing leads to many problems, lots of drag, hard to vent due to tank wrap, and it tends to lead to being grossly overweighted because you can get away with it.

I routinely dive steel doubles in the moderately cold waters of southern california with a 40 lbs wing.

Let me echo others recommendation that you seek some appropriate training. Doubles offer increased redundancy and gas volume, but also present increased risks. You need to recognize, understand and manage these risks.


Tobin

 

[motorcitydiver]

Ok guys (and gals) I appreciate the information you gave. I understand how important training is and I have every intention of gaining a higher level of training before going beyond my capabilities. I wasn't aware of the issue with 94 wing, especially since my LDS/instructor advised me on it. All I wanted to know was if most double divers used one or two SPGs. Thanks for the the help!

 

[cool_hardware52]

I wasn't aware of the issue with 94 wing, especially since my LDS/instructor advised me on it.

You might want to shop a bit for instructors.....

 

[motorcitydiver]

By the way, no hard feelings. Most of you have a lot more experience than I.