Tiny Doubles...

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

could not aggree more, I have not strapped on my my mono 15l since my double 8.5 arrived (the one you intend to buy, though I got it through my LDS).

no rolling around in the water any more, the additional weight on land is noticeable but manageable, double 12s are too heavy for my recreational diving
 
I have dove twin AL30s an twin AL40s in checking them out to see how they might work for small people, and they are much lighter than one 60 or one 80.

Although on the scale there is not such a difference, they feel so much lighter.

I have also dove the triple 30's (?) in the Cousteau packs and those are cool too.

I used triple 30s as a bail out when doing narrow pipe penetrations. I stripped them down from their original form to just the tanks and a DIY harness so the tanks would rest against my back. They were perfect for that job but not comfortable so when I got out of commercial diving I broke them down to double 30s. I attached them to a commercial diving harness so they are only a 1/4" off my back making them very stream lined.
 
Old thread but can anyone give their opinion on diving twin HP40's (Faber/Blue Steel) compared to twin LP50's (Faber)?
 
The FX40 is a new cylinder and is really geared towards rebreathers, short (18") and fat (5.5"). While the same diameter as the LP50 but being so short I am not sure how easy it would be to trim out for the average person.
 
I love this thread! Those tiny doubles with the double hose are slick. I have removed the OMS 45's from my rebreather. I have had a few thoughts about what to do with them to including selling them. I might play around with them either doubled up or for side mount.
 
I currently have a set of HP 120's I dive with. Since moving to doubles I really enjoy them and prefer the redundancy. I only dive singles now when we have students. As many have stated they can be quite cumbersome however for short shallow dives. Shallow meaning non tech dives. I spend a lot of time diving around 100-110 ft on solo dives. I am seriously considering a set of the Faber LP 50's. I do have some questions though if anyone is up for answering them. I work for a dive shop, as an DM/AI and boat captain. I do my own fills and VIP's so that is not an issue. what I do want to know is has anyone tried to transfill from AL80's? when we load the boat (no compressor on board) its no biggie for me to load the same two 80's I would be diving with for the day, but use them as a transfill from 1st to 2nd dive. I realize 1 80 would not give me a complete fill but would topping off from a 2nd 80 get me pretty close? Also diving a single AL80 with an AL backplate I need 16lbs, in a drysuit. with the 50's by just doing the math I am figuring I need 14lbs. I have 2 Al backplates. Both Mares XR. 1 is set up for singles, the other set up for my double 120's. I intend to just move the doubles wing and BP back and forth between the 120's and the 50's. That being said.... the doubles wing I have is the Mares XR 52#. I certainly don't need that much lift for the 50's but, is that going to be too big and create more drag and a taco effect, or will it be fine until I pick up the smaller 44# from Mares? Long post I know just looking for some insight before I pull the trigger.
 
I will take a stab at this. I have the faber lp50's as doubles. if you dive them down to say 500 psi on your first dive and transfill with an al80 at 3000 psi it should equalize at about 1532psi. then if you top it off with a second al80 at 3000psi it should be about 2138 psi.

(p1 * c1 / rp1 + p2 * c2 / rp2) / ( c1 / rp1 + c2 / rp2 )

p1 & p2 are the current pressures in psi of each cylinder

c1 & c2 are the rated capacities of each cylinder (e.g. 80cuft, 19cuft)

rp1 & rp2 are the rated pressures of each (e.g. 3000psi, 2400psi)

as for your wing I have a 44# wing and with the double 50's being low profile I don't think I get a full inflate of the wing so my lift is cut down some as with the larger tanks the radius of the tank lets the wing inflate more complete. I think the 52# will be fine.
 
I will take a stab at this. I have the faber lp50's as doubles. if you dive them down to say 500 psi on your first dive and transfill with an al80 at 3000 psi it should equalize at about 1532psi. then if you top it off with a second al80 at 3000psi it should be about 2138 psi.

(p1 * c1 / rp1 + p2 * c2 / rp2) / ( c1 / rp1 + c2 / rp2 )

p1 & p2 are the current pressures in psi of each cylinder

c1 & c2 are the rated capacities of each cylinder (e.g. 80cuft, 19cuft)

rp1 & rp2 are the rated pressures of each (e.g. 3000psi, 2400psi)

as for your wing I have a 44# wing and with the double 50's being low profile I don't think I get a full inflate of the wing so my lift is cut down some as with the larger tanks the radius of the tank lets the wing inflate more complete. I think the 52# will be fine.


Those r the numbers I had been looking for. Awesome! Thank you. Yeah I am thinking this would be an expensive endeavor for a novelty that would not be optimal......:(
 
If I am able to find a set that someone is wanting to part with for a low price I would still do it. But not gonna invest a lot in them for a novelty.
 
they do dive very nice, they trim well, being low profile they don't roll you, and more compact than an al80, redundant and great for penetration diving. they are steel they are heavy but enjoyable to dive.
 
https://www.shearwater.com/products/swift/

Back
Top Bottom