Tips for backmounting an AL19 pony?

[Wibble]

Kent Tooling makes pony brackets.

Kent Tooling pony brackets

 

[hedonist222]

Hello all,

I’m looking for tips on how to backmount a Luxfer AL19 pony tank on my primary gear, which is an Apeks Black Ice back-inflate BCD - The tank strap is quite low on this model. I have a standard tank strap, not the Griplock shown here, and also weight pockets are the back.



I’m looking exclusively for a backmounted solution, as I shoot underwater video, including macro which requires me to get really low, and do not want anything in the way on the front or sides, so no sling type solution for me.

From what I’ve gathered, the options would be to clamp/bracket it to the main tank (typically steel 10 to 12L or AL80 style aluminium tank), or some sort of pouch/hoster or strap solution.

What would you say works best for an AL19 cylinder?


Thank you!


PS. yes, I do know a backmounted set of doubles or sidemounted set of twins is a superior “solution”, but this is not practical for what I do.
I will be using the rig on shallow (20m max) solo shore dives with the camera, for which I prefer minimal redundancy in the rare case of a critical air loss. This is to bring me back to the surface, and yes, I’ve done the maths.

Shark mounting system: Home - Shark Manufacturing, LLC

I've used one for about four years now. Great.
The ingenious design here is two fold. First there are two independent mounting points and one of them (the J hook neck) completely prevents the unit from disconnecting from your primary unit.

 

[afieldofblue]

I'd like to thank you all for your input, it's very helpful.

To sum up so far, the suggestions for a backmounted rig seem to be:

- the Shark system, which hooks onto the valve and with a band that clips around the tank:

- a Trident-style pin released mount, which hooks on a single cam band:

 

[afieldofblue]

- A slider system, either half DIY or Kent Tooling:

- Or a simple Zeagle Dual camband strap system:

 

[afieldofblue]

One thing i'm a little worried about with the Shark system (which I can maybe get here as they seem to have a distributor in Okinawa, BUT it's on-base, so off-limits... not sure) is the compatibility with local Japanese cylinders.
Not the pony, which is a standard (but recertified) Luxfer AL19, but the actual primary tanks, which come in shapes a little different from AL80 style long tanks.
With the non-adjustable bar + valve hook, it seems pretty set on long cylinder designs like and AL80 or AL100, and not sure how it would fare with Japanese tanks like these for instance:

This is by far the most common steel tank here for instance, chubby, short, the works.

Other Japanese models include:

Size / format-wise, i'm not sure how compatible a set-length contraption like the Shark would be with tanks like these.
They do have AL80s in some places, but it's not always a given.

cheers

 

[34109411]

I don't think you understand how unobtrusive a correctly side mounted pony is. Even an AL40 or LP50 disappears.

i do carry a AL30 ok my side and i barely noticed it.

 

[landphil]

No, you only think it does.

I backmounted a 19cf bottle for years, over hundreds of dives. I carry a camera with video lights on all dives.

I finally decided to try slinging it under/behind my left arm, and now I feel like a freaking idiot for not doing it sooner. The main advantage for me was that slinging eliminated the problem whereby the bottle would not allow full inflation of the bladder on that side, and I'd need offsetting weights to compensate for the negative buoyancy of the bottle, those two things made it impossible to get my trim exactly right, and also sometimes I wouldn't need weight at all with large steel tanks yet I'd have to add 2-3 lbs to offset the bottle.

You should at least try slinging it. The needed hardware is minimal, you can probably do it with what you've already got available. Don't waste 2 decades like I did only to say "Damn I should have done it this way in the first place".

I backmount my AL19, but could see all of these being an issue for me if I was wetsuit diving. But in my drysuit I’m running 10 lbs of trim weight on my upper cam band. Throwing in 4lbs instead of 5 on the pony side balances me out perfectly. And as a bonus, the full weight pocket makes it so I can’t rotate the pony close enough to my wing to keep it from inflating (never really use my wing outside of surface floatation, though) Fortunately, I only wear a wetsuit when I have to do a sketchy beach entry for some survey work, or when I’m on vacation; and all of those would be without a pony.

 

[NW Dive Dawg]

I used to use the Pony Tamer system but it required bands / brackets on the primary tank.... Now I have the Quickdraw system and won't ever go back. Rock solid attachment.

 

[afieldofblue]

I used to use the Pony Tamer system but it required bands / brackets on the primary tank.... Now I have the Quickdraw system and won't ever go back. Rock solid attachment.

Thanks - how adaptable is the Shark system in terms of primary tank length? Would it be possible to use with a short tank like a steel 10L or is the valve hooking pole too long and only fit for AL80 style long tanks?
The typical rental steel tank in Japan is the 10L steel, and I'm wondering how a mount like this would fare should longer / aluminium tanks be unavailable.

Typical Japanese steel tank vs. Japanese aluminium

steel rentals



thanks

 

[justinthedeeps]

No, not practical for multiple reasons - major one is that I'm in Japan and tanks need to be KHK certified to be filled, and very few types of cylinders are imported here - a pony itself is hard (near impossible...) to find, the one I'm buying was actually re-KHK certified, including the valve, in Japan, which is a complex process.
See the O2+N2 restamping (instead of air) + official Japanese markings

View attachment 895410 View attachment 895411
Most people using smaller cylinders (for rebs or stages) will use non-KHK cylinders, and fill them privately (which is illegal). They cannot be hydro'ed as well. Same goes for valves.
The seller will have it rehydro'ed for me before shipping. It's a unicorn here, where DOT certified tanks cannot be filled or hydro'ed.
So LP50 twinsets... not going to happen in my neck of the woods.

The other issue is weight for shore dives with a camera, and price of fills, equipment cost, manifold, all for limited benefits - it's just not practical.
I'ved dived with a 3L pony a few times in the past (borrowed rig) and really liked it. It was strapped-on (don't remember exactly how, this was a while back) but not floppy at all.

Only dived there briefly so far, thanks for giving some context re: some of the odd ways SCUBA there seems to be held behind vs. modern global standards (hard to find DIN/convertible valves too?)