swimming a stage

[Al]

Luxfer & Catalina tanks have slightly different buoyancy characteristics but I wouldn't think it enough to notice all that much.

FWIW, mine are Luxfers and they are all tail heavy (no boot) when filled to around 2800psi or greater. Less than that and the rear/bottom starts to float.

Catalina tanks are really bottom heavy and don't work well as stages. Putting a bicycle inner tube on the tank and adjusting the air in it helps the stage bottle to behave a little better, but is a PITA. I like to add a bit of helium to my stages. 30% helium makes a Luxfer tank behave perfectly.

[Luxrok]

I wrote a post with some nifty pictures. It covers the evolution of how I cane to mount my stage bottles when diving backmount or CCR. Take a read and let me know what you think.

http://www.quietdiver.com/68/an-appr...backplate.html

Hans

[aainslie]

A trick I learned recently - have two D rings, and change it as it empties. One ring can be waay back, almost like a SM mount point. The next one can be in a more conventional position. At the beginning it'll hang DOWN and flat, at the end UP and flat. Very cool!

...And sicne you're at it, consider using an SM type bungie at the top. Basically sidemount the thing. It'll be much more out the way.

Edit - just read Hans' post. That's even better!

[RN]

Catalina tanks are really bottom heavy and don't work well as stages. Putting a bicycle inner tube on the tank and adjusting the air in it helps the stage bottle to behave a little better, but is a PITA. I like to add a bit of helium to my stages. 30% helium makes a Luxfer tank behave perfectly.

I've got a Luxfer and a Catalina as stage tanks and my Luxfer seems to be more tail heavy than my Catalina. Significantly so. I'm in the process of changing tanks around and converting some of my student tanks that are Catalinas into stage tanks and using the Luxfers as student tanks. As for correcting the problem, because my Catalina starts out tail heavy, I'm working on carrying my bottles behind me...but I am diving sidemount so that wouldn't work for backmount. If I were still backmount, I'd try carrying them like sidemount bottles. Clamp a d-ring onto your left bottle close to the front and clip your stage bottle to that.

[satchmo0016]

Stairman, due to having a small waist stages would lay similarly on me... What I ended up doing is using the Armadillo Butt plate and using bungees mounting it similar to when diving side mount.

The plate is pretty straight forward, those male/female bolts work well for mounting it.

For the bungees, I actually cut a piece of webbing about 4-5 inches wider than the plate, put a grommet in center and 2 grommets on either side for the bungees. Then I drilled a hole in the middle of the plate a few inches down from the top hole that your bolt for you tanks goes though, then using another male/female bolt to attach the webbing to the plate.

Doing it this way the stage tents to "ride" the same way whether full or empty. Nicely tucked away under the arm.

Also keep in mind that you may have to adjust your regulator set up so you can actually see your pressure gauge.

if you want to see pictures or anything send me a PM.

[satchmo0016]

I wrote a post with some nifty pictures. It covers the evolution of how I cane to mount my stage bottles when diving backmount or CCR. Take a read and let me know what you think.

http://www.quietdiver.com/68/an-appr...backplate.html

Hans

A novel idea on your link there..

but I dont' understand why you did some of the things you did it just didn't make sense...

The door handles do stick up and are in the way diving anything longer than 95s depending how high your bands are... but after using the 95s I didn't have any trouble as far as trim and control.

[mwenner]

Brilliant!

A trick I learned recently - have two D rings, and change it as it empties. One ring can be waay back, almost like a SM mount point. The next one can be in a more conventional position. At the beginning it'll hang DOWN and flat, at the end UP and flat. Very cool!

...And sicne you're at it, consider using an SM type bungie at the top. Basically sidemount the thing. It'll be much more out the way.

Edit - just read Hans' post. That's even better!

[Luxrok]

but I dont' understand why you did some of the things you did it just didn't make sense...

The door handles do stick up and are in the way diving anything longer than 95s depending how high your bands are... but after using the 95s I didn't have any trouble as far as trim and control.

I had trouble reaching around the door handles whether I was using my Megalodon or double 80's. With the double 80's, they actually hit the bottom of the tanks.

Which things confused you? If you let me know specifically, I can spell out my thinking for you or the events that lead to the specific choice.

Hans

[satchmo0016]

I had trouble reaching around the door handles whether I was using my Megalodon or double 80's. With the double 80's, they actually hit the bottom of the tanks.

Which things confused you? If you let me know specifically, I can spell out my thinking for you or the events that lead to the specific choice.

Hans

Nothing confused me, just some seemed unnecessary to me.

I had the same issue with lp85s, and why I went to 95s diving like that.