any benefit to dual AL40's

[M-Cameron]

just curious......is there any benefit to dual AL40's or even dual LP50's over a standard single AL80?

and connecting them with a single yoke manifold(Thermo PVD One-Piece Manifold)


i feel like it could give you the same amount of air in a smaller package and more secure attachment (albeit at 5X the cost)

 

[Protondecay123]

Steel LP 50 twins can be nice to work on your doubles skills, pool sessions etc. pretty costly though.

 

[Bowers]

My wife dives sidemount 40’s and we will be getting 50s for her soon. It gives redundancy that you cant achieve with a single tank and is easier to transport/carry. I have also dove BM lp50 doubles with an isolation manifold. This also gives redundancy, is great for practice tec skills and used by a number of solo divers. With a cave fill 2 lp50s is almost double the gas of an aluminum 80.

 

[DeepSeaExplorer]

50s are too short. If you’re of average height, you’ll be hunching over to get them on and can’t the load off while seated.

They’re not much smaller/lighter than 80s, but a lot less functional. You would be able to do a two tank dive with 80s, probably not with 50s. You then have a logistical problem doing a simple two tank dive.

 

[Protondecay123]

50s are too short. If you’re of average height, you’ll be hunching over to get them on and can’t the load off while seated.

They’re not much smaller/lighter than 80s, but a lot less functional. You would be able to do a two tank dive with 80s, probably not with 50s. You then have a logistical problem doing a simple two tank dive.

25.2 inches versus 25.9 inches according to @tmassey chart. About 3/4 inch. The LP 50’s are 5.5 in diameter.

 

[DeepSeaExplorer]

Ok, I missed the LP part. I thought we were talking AL50s.

 

[Protondecay123]

Ok, I missed the LP part. I thought we were talking AL50s.

If you just look over some specs, two of them are in the neighborhood of an Al80, buoyancy and volume wise. And you can play twins or sidemount with them. Playing around with trim ideas,, practicing some drills, etc. I've even taken them rec diving a few times just for the fun of it. I always love it when the Dive Shop wants to charge me for two tank fills! That's like a Canary in the Coal Mine for a Dive Shop to only do essential business.

 

[MichaelMc]

I really like my twin AL40's. As said, the tanks weight a hair less than an AL80 with similar buoyancy. So if you have some extra lead, the doubles hardware, extra valve, and extra 1st should be no weight penalty on land. Lead and brass/steel being close enough in density to not matter much.

The bonus is you have redundancy in a trim package. Plus you get to play with doubles skills in a tiny package, if you want to. Having the in a manifold should cut down on shops charging for two fills. (I love them as sidemount, so I only like them as doubles.)

I'm not sure I'd connect them with a manifold with one outlet. You'd gain by them being closer to the body, and maybe more streamlined. But the big benefit is with a normal isolation manifold and two outlets.

 

[seeker242]

even dual LP50's over a standard single AL80?

More gas, especially if you can get them overfilled. Although, doing 2 tank dives, the people I dive with who dive them they bring 2 sets.

 

[DeepSeaExplorer]

More gas, especially if you can get them overfilled. Although, doing 2 tank dives, the people I dive with who dive them they bring 2 sets.

Taking two sets isn’t always an option. Frequently, there isn’t enough space on the boat.