Can't get trimmed out.

[Scubaroo]

kcanty once bubbled...
You don't really have boots on your tanks, do you?

Kell

You can buy circular weights to go inside of a tank boot, but I think they're 5lb apiece - maybe you could cut one in half and add half to each tank boot.

Double tanks (or any tank) generally shouldn't be left standing unattended, so there's probably no real reason to leave the boots on.

 

[thethumper]

kcanty once bubbled...
First of all I wouldn't recommend overfilling aluminum tanks.
I do it all the time with steels but I'm cautious with aluminum
but it's your choice.

Also I have read that catalina's have undesireable bouyancy
characteristics compared to luxfers. I don't have any trouble
with my double luxfer 80's.

Which hole(s) of the DR classic are you using? All recent ones
have 2 sets of 3 holes for placing the wing on the BP. Using
the bottom hole of the 3 could help.

Are your fins neutral, positive or negative in the water?
Jet fins are definately negative especially with spring
heel straps. They may help if you don't have negative
fins.

You don't really have boots on your tanks, do you?


Kell

The Catalina's are 3300psi Catalina 80's. 35# -5.8 full, "0" (neutral) empty.

Using the bottom hole on the wing was to be my next thing to try. Get my boyancey to the top & further away from my butt. It's boyant enough.

My Blades are deffinantly negative. I have spring kit on them as well.

And... no... I don't REALLY need the boots, but if the bottoms take a hit.... it'll be the boot & not the tank.

Thanks.

 

[pescador775]

Clearly, you have too much weight between the shoulder blades. This is a common problem with DIR rigs. You'll notice the number of novel engineering approaches to your problem. That's because it takes an engineer to set up one of these rigs in the first place but mostly ends up trial and error. I suggest you stand by until 'genesis' sees this thread. He says that he is able to use these kits with decent trim parameter. I'm not sure if he's savy on fresh water though. In the meantime, 'lucid' has an interesting suggestion. Also, playing with fins and ankles is a non starter, wait for serious advice. You may have to trade in the heavy aluminum tanks or keep for salt water use only.

 

[WreckWriter]

Do any of your buddies own a set of Luxfer doubles? If so, try to do a dive with those tanks and no other changes. I'm betting the Cats have odd buoyancy characteristics as I've heard their 40 cf tanks do.

I have a set of "Super 80s", short tanks with close to neutral buoyancy empty that dive this same way, forcing a head down position. I've been unable to fix it easily so I don't use them much. On a shorter person they might work well.

One option you might try is to get a V-weight and cut it in half, just use the "bottom" part of it.

Tom

 

[Scubaroo]

pescador775 once bubbled...
Clearly, you have too much weight between the shoulder blades. This is a common problem with DIR rigs. You'll notice the number of novel engineering approaches to your problem. That's because it takes an engineer to set up one of these rigs in the first place but mostly ends up trial and error.

I'm sorry pescador775, but that is one of the dumbest statements I've ever seen posted on ScubaBoard.

David didn't say anything about his rig being or attempting to be DIR, and backplates, wings and doubles have been around a lot longer than DIR. You're the first one to mention it in this thread. It's a simple trim problem, and instead you use it to take a cheap shot.

 

[thethumper]

WreckWriter once bubbled...
Do any of your buddies own a set of Luxfer doubles? If so, try to do a dive with those tanks and no other changes. I'm betting the Cats have odd buoyancy characteristics as I've heard their 40 cf tanks do.

I have a set of "Super 80s", short tanks with close to neutral buoyancy empty that dive this same way, forcing a head down position. I've been unable to fix it easily so I don't use them much. On a shorter person they might work well.

One option you might try is to get a V-weight and cut it in half, just use the "bottom" part of it.

Tom

Actually my buddy who bought the same BP/Wing/manifold I bought & dove w/yesterday dove Luxfor & was fine. Hhhmmm.

 

[Scubaroo]

I believe O-ring has a set of Catalinas doubled up - try shooting him a PM. He might be on vacation at the moment though.

 

[thethumper]

Scubaroo once bubbled...
I believe O-ring has a set of Catalinas doubled up - try shooting him a PM. He might be on vacation at the moment though.

He's always on vacation. But I'l PM any how

 

[pescador775]

David didn't say anything about his rig being or attempting to be DIR, and backplates, wings and doubles have been around a lot longer than DIR. You're the first one to mention it in this thread. It's a simple trim problem, and instead you use it to take a cheap shot.

Don't be sorry, be right. True, the ATPAC was around back in the mid 70's, initially got a lot of attention from Skin Diver, then died. Later, back yard experimenters started tinkering with the design but it didn't take off until DIR hype gave the thing a boost. It's an improvement, for some people.

 

[Wreck/Tec]

I have an OMS System. The DIR school discourages elastometric bands on the wings. They view them as an entanglement hazzard. I tried to dive my twin 98s all summer with out the bands. I to was severely face heavy. I added the bands to my 100 lb wing and problem solved. There was too much air towards the rear, and air shift was to radical. DIR has many good points. In my opinion, that wasn't one of them! Hope it helps.......
Wreck/Tec