twin LP72s

[jcaplins]

What type of spacing do you have on your bands? This is certainly a cheap way to setup a doubles manifold if it will fit:
DGX Premium Cylinder Valves - Dive Gear Express (the $100 doubles manifold & valves).

That looks like a good option... I'm seeing a few of those used as well.
The bands are 8.5" center-center.
I also test fit a 7.25" diameter band (from my HP100's)... it didn't clamp so well, and pushed the spacing out to almost 9".

 

[captain]

Okay, mine has an N in a diamond, so it's a norris tank? Damn this will make the plus rating difficult.

I know a fairly reasonable fire testing shop that I think I can get to do the + rating. I just don't want to have a 65cu ft tank.

It really shouldn't, since all 72's were made to the same 3AA specifications the REE should be the same. As you have learned convincing hydro shops of that is an entirely different matter. If the REE was different for different manufacturer's then logic would indicate it would have to be different for each and every individual tank as there is some variation in individual tanks from the same manufacturer.

 

[scubastingray]

It really shouldn't, since all 72's were made to the same 3AA specifications the REE should be the same. As you have learned convincing hydro shops of that is an entirely different matter. If the REE was different for different manufacturer's then logic would indicate it would have to be different for each and every individual tank as there is some variation in individual tanks from the same manufacturer.

Okay, this is great news. My instructor actually just purchased hydro equipment and is getting everything in order in the next few months. He has said it should be no problem to get the plus ratings from him.