Manifolds does one size fit all?

[Bigeclipse]

All,
I recently acquired some doubles and love them. I will be converting my current set of single 100 Faber fx 100s to doubles as well. I understand tank bands will depend on tank size but what about manifolds? I understand older tanks have different thread pattern so I need to watch out for manifolds designed for that but more concerned about things like the width of the manifold...etc.Thanks

 

[guruboy]

The manifold has a range it works with and needs to fit the bands spacing. The crossbar with the isolator lets you adjust the width based on how far you screw it in.

The bands need to fit the tanks.

 

[2airishuman]

The newer manifolds, the ones with an O-ring seal and reverse threads on one side of the crossbar, have enough adjustment range that they are supposed to fit either 7.25" or 8" diameter tanks with most bands, which leave around 1-1.25" or so of space between cylinders.

Compatibility problems come up with smaller tanks, like LP50s, where you either need bands with a wider tank spacing, or a shorter crossbar.

Older manifolds have less adjustment range and may also pose problems.

 

[Bigeclipse]

thanks I

The newer manifolds, the ones with an O-ring seal and reverse threads on one side of the crossbar, have enough adjustment range that they are supposed to fit either 7.25" or 8" diameter tanks with most bands, which leave around 1-1.25" or so of space between cylinders.

Compatibility problems come up with smaller tanks, like LP50s, where you either need bands with a wider tank spacing, or a shorter crossbar.

Older manifolds have less adjustment range and may also pose problems.

was looking into the DGX manifolds and bands for cost purposes, not sure of quality though. Reviews seem good.

 

[Pullmyfinger]

I have two sets of doubles that have Dive Rite bands and manifolds, and one set that has the DGX manifold.
They appear to be the same quality to me. The finish, appearance, number of turns to open/close is the same.
The DGX valves I have are the longer neck versions............

DGX Premium Dual-Outlet Long Neck Manifold w/Isolator | Dive Gear Express®

...........as opposed to the shorter neck Dive Rite valves.
No functional difference between the two.

Regarding the different threads you mentioned in your original post: The old "genesis' valves has a 45 degree angle, and were a different diameter and thread pitch.
Also, European spec tanks and valves have different threads. They don't have burst disks on the valves, which will give you a quick indication that they are Metric.

I hope that is of some help to you.

Cheers,
Mitch

 

[tbone1004]

the dgx valves are perfectly fine. All modern bands and manifolds have the same nominal spacing of 8.5". There are a few narrow manifolds and a few that offer no width adjustment so you have to make sure your bands match, but any of the new ones *last decade or so* are all on the standard 8.5" spacing

 

[Doby45]

I just replaced the valves on my AL 80s to the DGX Long Neck valves so that I could use them side mount or manifold them and use them back mount. Excellent valves for the money..

 

[2airishuman]

I have a couple of DGX modular system valves and have been happy with the quality.

 

[DogDiver]

Bands and manifolds are cylinder specific.

 

[Scared Silly]

Modern manifolds come two widths 185mm and 215mm. Though I have seen a 190mm from Blue Steel. The 185mm crossover typically does not have an isolator and is specific to LP45s and LP50s with "narrow" bands. The 215mm manifold will fit cylinders from 6.75-8.0 inches in diameter. But can be used with smaller cylinders with "wide" bands.
In short, one just needs the right bands for the cylinders.