Rotating Crossbar vs Captured O-Ring?

[Tortuga68]

I wonder if the orings are all engaged at max c to c adjustment

So they are adjustable?

 

[rjack321]

Thanks. The bands in fact could pass as Millwork bands--but I guess bands are bands. They are designed for nominal 8.5" spacing when locking down 6.9" tanks. If the c-to-c spacing on bands designed for 7.25" tanks does not change significantly when locking down 6.9" tanks (I would have thought the spacing would change quite a bit), then my setup should work, the tank diameter difference being only .06"). My technician didn't think there would be a problem, but we'll see. I'm heading out of town (Hawaii, actually, dive gear in toe) for a week and my tech too will be out of town, so we'll attend to the task in about 1.5 weeks.

The tank walls get slightly further apart, yes. But the tanks themselves are 0.25" less in diameter so it seems to work. No promises.

I know this because my first doubles were assembled with the wrong bands at the shop I bought them at. Found out at the next VIP time that the bands didn't precisely match. Yet they worked. I have since gotten the correct bands for the Faber 85s since I have 6 sets of doubles by now.

 

[elan]

Here's the reply from the people at Thermo when I asked them about the adjustability of their rotating crossbar manifold:

"The Center to Center on this valve is 215mm or 8.46". It is adjustable +/- 0.1"."

That's not much adjustability, but I guess it is something--hopefully it will be enough to accommodate my twin Faber 72's (new shorter ones, with 6.84" diameter), which I am mounting onto bands custom build for 6.9" diameter and 8.5" spacing.

You said "current," did anyone ever make adjustable barrel O-ring style manifolds? Or were you leaving open future possibilities?

I have a set of LP72s which are 6.9" with a thermo manifold and OMS 7" bands. they work fine for more than a year now.


7.25 bands will not work on 6.9 tanks. The plates get so close to each other that they do not provide rigidness. I tried it with halcyon and dive rite 7.25 bands. You have mentioned you are making custom bends so you should be fine.

 

[mahjong]

The bands are custom to achieve 8.5" C-to-C spacing with 6.9" tanks (old steel 72's, ~25" tall)...my tanks are 6.84" (newer shortie Blue Steel Faber 72's, 20.5" tall). I'll be using a Thermo rotating crossbar manifold.

I have a set of LP72s which are 6.9" with a thermo manifold and OMS 7" bands. they work fine for more than a year now.


7.25 bands will not work on 6.9 tanks. The plates get so close to each other that they do not provide rigidness. I tried it with halcyon and dive rite 7.25 bands. You have mentioned you are making custom bends so you should be fine.