Bands and Manifolds for AL-30 or 19s? (Twins)

[beanojones]

Train like you fight, so to speak. The problem with double AL 30s is that small stature or not, they'll NEVER dive with them anyway if they truly go into technical diving and at some point will have to go with larger tanks (HP 100s etc).

At a minimum consider a pair of LP 45s.

(They'll never use twin 100's. On my Trimix dives, I was in twin LP 130's. The Japanese guy was in twin LP 67's and that was only for the other members of the team. Based on his own SAC, he would be Twin LP 45s/46's.)

At that point though, it gets back to the question of where to buy manifolds and bands for smaller tanks? If I can find manifolds and bands for lp 45's, wouldn't they also fit al30's? (I like to avoid steel when I can, they really don't last in the tropics, they are much more expensive, and with thin or no wetsuits they are too negative.)

Apparently I could pay to have someone make the bands. But without manifolds, it is beside the point.

 

[beanojones]

Ok, like has been said, training doubles is for decompression/overhead diving and that kind of diving requires reserves for you and your maybe not so small lung volume buddy.That said....Dive Rite used to make them and....Stainless Steel Double Tank Bands

Did the DiveRite bands just make small tanks properly spaced for using a larger manifold? If that's the case I can just have the bands made to fit my tanks and whatever manifold I use?


(ABout the use of doubles: they are for GUE classes, or for doubles experience dives, or for whatever divers wearing doubles are doing on a dive. Some people use doubles because that's what they got, or because doubles feel more stable underwater. I dove doubles before I was even certified as an open water diver, (let alone a tech diver, let alone a tech instructor) because that's the guy had on his boat. Lots of people in Hawaii use twin 80's and twin 72's bolted to in the old hard pack Scubapro palates with no BCDS, because that's what they got.

In my case, the point is to make an experience available to my customers without making it a grind. I am not diving with any customers planning on relying on them for anything ever, whether it is a training dive or not. So their doubles are hardly there as reserve for me. More to the point, I am not trying to get them to perform tech dives; I am trying to give them a 'Tech Experience' prior to them being 'tech certified' in the same way I take uncertified divers diving to give them a 'Dive Experience' prior to them being certified. It's going to be shallow shore dives in 40 feet of water or less. Diving in 'tech setup' doubles is something I have been asked for when they see my setup in the corner of the shop; it's something that there is demand for. I just need the equipment to make it work. They certainly cannot wear my gear, anymore than they can wear my BCD, wetsuit or fins. It just would not 'fit'. )

 

[Otto]

Detroit Mud Puppy on this board is a manufacturer of tank bands and back plates and has made several sets for the Faber lp 45cf cylinder and standard manifold. On flea bay his company name I think is technical solutions and he does list product there. There are other sources of bands from various manufacturers if you look around. Also pay attention to the equipment ads as I have recently seen 4 sets of the 45's sold with at least 1 set here. Good luck.

I don't know what bands and manifolds they are but 2 sets of these are on the board right now!

 

[Ragnar]

Depends, older manifolds are shorter, there are bands available for each and the other link I posted will make whatever spacing you want if needed. Read the notes on the NESS site regarding their bands and also the OMS.

Tanks - Tank Bands - Northeast Scuba Supply

Dive Rite 200 Bar 5.5" Tank Manifold - From Prime Scuba

Dive Rite 5.5" Tank Bands - From Prime Scuba

 

[beanojones]

Would I run into stability issues with custom bands with a manifold not designed specifically for that tank size?

Say I got bands made for AL 30's (5.25" or 4.87") diameter using the 5.5" manifold, or even, using an manifold made for 7.25" tanks (which I already have, and get more of easily), and then getting custom bands for 5.25"/4.87" tanks.

Does adding separation between the tanks make the whole thing less stable, or are two inch bands strong enough to make that not an issue?

 

[Ragnar]

Stability is fine, they aren't that heavy. People are banding Al40's with 7Liter tank bands just fine, no need to have custom bands made for .25" less diameter.

7L tank diameter=140mm=5.5 inches, get the bands from NE Scuba supply, use standard sized newer manifolds and be done with it, or at least call them with your concerns. Report back

Neither Dive Rite or OMS show this size band anymore so whatever is out there is old stock I guess. I'd like to have a set of twin 40's but doing the math on it I can't justify the cost for such little usefulness with my western sized lungs

 

[beanojones]

What do other people banding 40s (or 46s for that matter) do with them out of curiosity?

 

[Lobzilla]

I am putting together a set of LP45s on a standard manifold for shore dives in the 40' - 60' range with rock entries/exits. The point is having redundancy without the weight of larger doubles that have 'too much' gas volume for these (cold water) dives.

I opted for the steel tanks because they can be transfilled easier, could be 'cave-filled' if necessary, and require less lead to sink the drysuit. The remaining thing to be seen is how they trim out.

 

[beanojones]

I am putting together a set of LP46s on a standard manifold for shore dives in the 40' - 60' range with rock entries/exits. The point is having redundancy without the weight of larger doubles that have 'too much' gas volume for these (cold water) dives.

I opted for the steel tanks because they can be transfilled easier, could be 'cave-filled' if necessary, and require less lead to sink the drysuit. The remaining thing to be seen is how they trim out.

Please post your experiences when you get that set up.

When you say standard manifold, are you saying a 7.25"/8.00" tank manifold? If so, I really want to hear how it all works out. For me, if I could use the 7.25" manifold and just get custom bands to fit my tiny tanks, it would work out easier.

 

[Otto]

If you regularly dive twins the small tank set lets you use the same regulators, wing and back plate in a much smaller package. still keep your redundency, and uses the same skills as any other set of twins. If you need to haul your gear a long ways on your back it is nice to have a lighter load as you still have to haul the gear back out. When diving from a small boat it is easier to get in and out with the small tanks. If you solo dive it's nice to have the redundancy of twins and the weight of a single if you don't need the extra gas. Yes you can get bands for small cylinders that use a standard manifold. If you choose lp45's you get 90 cf on a regular fill as opposed to 77cf on an al80, that would be a %15 increase in usable gas. A set of lp45's with a mild "cave fill" could easily bring the gas supply to 102 cf, or %25 increase witout much more weight. Dive safe.