I have 2 AL80s....can I double em?

[wetvet]

Sorry if this is a dumb question. I am recently nitrox certified, and now my bottom time far outstrips my "available air" time on a single AL 80. I am interested in getting a set of doubles, but must do so on a budget. (more bottom time means I need a drysuit too ) I have 2 AL80 that I bought last year, and was wondering if and how I could join em together. Just buy a yoke, and get it attached when I get em O2 cleaned? Or do I need to buy special double tanks?

Thanks

Wetvet

 

[roakey]

SeaElite manifold from Divers' Supply (http://www.divers-supply.com/)

Highland bands from EE (http://www.extreme-exposure.com/)

Or, for AL80s I might go with "generic" bands from NESS (http://www.northeastscubasupply.com/).

How to put them together: http://www.cisatlantic.com/trimix/doubles/doubles.htm

Double 'em at cleaning/VCI time. Do it yourself unless you don't know the difference between a metric and SAE crescent wrench, in which case find someone in the know that can do it for you.

Please note that "someone" is very, very, VERY rarely the shop. And yes, I'm serious.

Roak

 

[The Chairman]

a yoke to yoke adaptor for AL80s but I don't think I ever would use it. Buoyancy charecteristics make them hard to dive.

Instead of buying valves and manifolds to tie them together invest in a steel 130 (the old lp104s) or two... or better yet get in better shape so you use less air... or become more relaxed so you use less air.

 

[AzAtty]

Roakey suggested EE for the Highland bands. Divers Supply sells them for about $30 less than EE. The bands don't show up on their web site, so you have to call to request them.

 

[C_C]

easier on the back and plenty of gas for the dives I do.

One consideration is if the cylinders are both from the same manufacturer. One Catalina and one Luxfer may be difficult to get set up with bands and manifold.

Having said that...no two cylinders are the same as far as dimensions go...small differences exist between all cylinders.

Try to get two cylinders from the same manufacturer's run or batch...closely numbered serial numbers is a good indication.

I have used OMS and Thermo manifolds for the AL 80's. Either provide sufficient valve options with screw-out inserts to be used with DIN first stages.

No need to spend all the cash on Highland bands for AL 80's...simply because the weight of the cylinders does not require the strength provided by the bands...I have them, but OMS/Diverite bands will give you sufficient support.

Bouyancy characteristics can be overcome by using a weight such as a P weight or V weight. Moves the weight to your cylinders or back plate and not on your belt.

If double 80's do not provide you with enough gas for your planned dives, consider different cylinders.

Good Luck,

C_C

 

[wetvet]

Appreciate the info. I dont think I'll ever get to the point that I can dive an AL80 long enough to make Nitrox worthwhile.....Mostly dive in 7mm suit in ~50F water. Dive with fairly experienced guys, and dont usually make em come up, so I feel I need more tank. This should work....bought identical tanks from the LDS last year....came in the same shipment, so should be from the same run....will check later.

Thanks again

Wetet

 

[mcrae]

Hi you can certainly dive with doubled alum. Don't forget you will need a backplate and wing to do it properly, some jacket style BCDs will work but a backplate is definately the preferred method.

Then you should get a second primary regulator so you have one for each tank to get real redundancy, something you should be concerned with if you are going very deep.

You may want to invest in a larger tank like a 104 or one of the newer versions of this. This will give you about 50% more air and down the road you can buy a second and pair it up.

I have been doing this for two years and am now just going to doubles.

Have fun
Gary