Slinging a Tank

[Dr. Lecter]

I slung a 20cf pony off a Zeagle Stiletto LTD before I switched to BP/W. I had a shorter pony with valve/first stage combo in a bag, but it worked about the same as a DIR-slung 30 or 40 would...the DIR-slung method will hang out a bit further unless you wrap the tail of the stage rigging.

The main problem is the lousy waist options for D-rings on the Stiletto. The only good one is too high up and close to the center, and its on the right side to boot. Depending on how long the 30 works out to be, you could go cross-chest, or slung on the right side only. Pictures here should be helpful to you:

20 cu ft Pony Bottle - Redundant Air - Zeagle Dive Systems

I went with the inverted approach, valve end clipped off at the right hip D-ring and tail up on the left or right shoulder D-ring (either one worked; cross-chest was a bit more compact underwater but got in the way of routing my Cobalt cross-chest and was more drag underwater, and I settled on right side for both clips eventually). Whatever you do, use a bungiee to secure your 40" stage hose to the cylinder rather than using an octo clip like shown on the Zeagle page. Much less odds of tangling something up or snagging the hose.

 

[PfcAJ]

I too have some questions. I slung the 40ft3 according to the steps on this site: DIR-diver.com - Stagebottle rigging however it does not show how much slack the bottle should have. Just testing it in the pool I felt it hung a little low. How low (or tight to the diver) should these be?

The top snap should be tight at the break of the tank. I try to make mine tight like a banjo string. The bottom clip should have about a hands width of slack.

 

[Peter69_56]

I always sling mine right shoulder D ring and hip D ring. 2 Occy straps on the cylinder to tidy reg hose, and short 6" HP gauge hose.

I have 3 litre (20) and 5 litre (40) slings and all are the same configuration. All are set up per DIR philosophy with rigging as its cheap, reliable and simple.

Always the highest O2 content cylinder right side, lower O2 content cylinder left side. All cylinders labelled on each side and top with MOD and % O2 and reg marked with white tape over the top (bridge area) showing MOD and % O2.

I have an Oceanic Probe BCD and it has enough lift for a sling as well, otherwise I use a wing & backplate but use the same configuration.

 

[Michael Guerrero]

I dive to the recreational depth limits frequently and now always dive with my 30 cu ft pony bottle. I dive a BP/W, so it might be a little different than your Zeagle.

I tried mounting it to the tank with the X bracket, but it's a huge pain in the ass, especially when you're switching tanks. Much easier to just side-sling it (I sling it on my left side). I also recommend putting a 90-degree (non-swivel) bend in the hose. You can get one for $8 from Dive Gear Express, works great.

Lastly, I put a 3lb trim weight on the right side of my tank band to help offset the weight on the left side, though you may be able to just do that with managing the bubble in your wing/drysuit. For me, the trim weight is easier.

Oh, and I have fixed 90-degree D-rings on my waist to make it easier to find/clip/unclip.

Here's a picture of mine attached to my wing.

 

[Peter69_56]

Lastly, I put a 3lb trim weight on the right side of my tank band to help offset the weight on the left side, though you may be able to just do that with managing the bubble in your wing/drysuit. For me, the trim weight is easier.

I find the issue of compensating for a sling tank on one side interesting. It had never entered my mind until I saw posts here about it, and to date have never had an issue, it has never felt unbalanced? Perhaps now I will be psychologically scarred and will have this paranoia about being unbalanced now

But seriously (if I ever can be) it just hasn't been a problem for myself or my wife, even with 11 litre (90) aluminium sling tank on one side on occasions. I don't have it positioned any different than the above picture. perhaps it tends to hang more toward my chest area and so a better centre of balance. Will take note (out of curiosity) next time I use it .

 

[Michael Guerrero]

perhaps it tends to hang more toward my chest area and so a better centre of balance. Will take note (out of curiosity) next time I use it .

Might be. Mine is pretty close to my body (6" or so) so it definitely stays to the left.

Of course, I may just have crappy SA on where the bubble is in my wing.

If you strap it on and it doesn't screw with your left/right trim then you're good to go. If you find yourself rolling left, and having to kick with one foot to compensate, like I did, try keeping the bubble in your wing more on the left side. if that doesn't fix it, then a trim weight is a reasonable option. Be aware of how it affects your head/foot trim though.

 

[waterpirate]

Given your current considerations about doubles, I suggest getting a BPW now rather than later and sling the tank. You can also purchase lp 72's doubled up ready to go on the cheap. That gives you 140 cubic feet of gas to use, with redundancy and no sling tank. The lp 72's are a great learner/ rec profile twin set that will serve you well. If you bite the bullet and go to twins, just make sure you are mentored in how to do a valve drill or you do not enjoy the benefit of redundancy. Most people I know switch to doubles and dive them for a while to get comfy before getting into valve drills. Just my .02
Eric

 

[Michael Guerrero]

On John Chatterton's blog I saw an article about diving double 50s. I thought that was pretty interesting. About the same gas as an AL80 and a pony, total redundancy, everything on your back, and not a huge package. I actually really like this idea, and if I ever settle down somewhere where it makes sense to buy my own tanks I would consider this option for recreational diving.

 

[chrpai]

Tiny doubles.... no thanks.

I typically dive an LP95 on my back and if solo diving in water deep enough to warrant it, an AL40 slung on my left. I don't need any trim weight on my right side to balance it out. I can hover motionless quite easily. I've got just as much usable gas as double 50's plus a boat more for redundancy.

Tiny doubles would just be alot more expensive to put together and to fill up after each dive.

 

[nv]

What is, if any, the benefit(s) of giving LP cylinders?