My first doubles!

[elan]

One gentlemen was kind enough today to part with his set. So they found a new home

The tanks still have some air in them, and the O2 percentage did no seem to have dropped it read one tenth lower than the air I used to calibrate. So I hope they are not rusty inside.

He claimed it was original set and was not dived for very long time.

I want to ask our experienced guys few questions.

First about markings. I was able to decode almost everything except few things.

They read ICC-3AA2150 which I assume 3AA alloy and 2150psi pressure. What is ICC ?
9624 I assume is the serial number ? It is 11117 on the other tank.
They are made by PST as I understand and the manufacture date/hydro is May 1954 ? Can the serial numbers be so far if they were originally sold as a set ? The hydro/manufacture date is the same on both tank as well as the rest of the informatiom is identical except 9624 and 11117

What does marking RENE mean ?
What does L in the circle with an arrow mean ?

I want to disassemble them, clean and overhaul the manifold.

Are there any specific things I should look for while doing that ? I was overhauling a mordern - termo manifold and valves but never did those vintage ones.

As I understand the manifold is 1/2 inch. Are there any o-rings there that I need to replace, like in the modern ones.

Thanks a lot, guy, for all your help in advance.

 

[captain]

ICC, the Interstate Commerce Commission was the governing agency before DOT. The change was around 1968 so tanks made before then will be stamped ICC instead of DOT
Rene is Rene Bossoz the original owner of US Divers Corp.
The manifold uses 1/2" pipe thread with no O ring and it will take a large vise and the correct tool to avoid damaging it and likely a strong arm to remove it.

You can get the information here Vintage Double Hose • Index page under manuals and catalogs. I have done a bunch of them and have some spare parts, PM me if you have problems.

They appear to be in very good shape.

 

[Gilldiver]

Nice clean early tanks and are in the collectable area for some. If your LDS will not do them, take them to the Hydro shop yourself. The Hydro shop will have the strap vise to hold the tank and the wrenches to get the valves off as they see pipe thread valves all the time. Also, go to VDH and print out the PSI Rounding out procedure and RIN number information and the Hydro shop should be able to give them a "+".

The L in the C is the symbol for Cochran Labs who did the hydro testing for Pressed Steel.

Where are you? If there are any problems we can help you find a Hydro shop.

 

[elan]

Thanks a lot, gentlemen, for all the information and offers. I live in Montreal but do most of my tank related service in Ottawa. The owner of the tanks had access to a compressor so I believe this is why the tanks have no other hydro stamps other than the original.

I will check through the manuals on VDH. I actually downloaded the 54 catalog and I saw that the 54 tanks came with only one band and the harness. So they were not probably sold in 54. But the 56 catalog shows the pics of the tanks with 2 bands and the harness.

Thanks a lot again.

 

[John C. Ratliff]

The military harness that you have was always sold with two bands. Here is a photo of a US Navy diver using a set of twin 72s in the 1950s with two bands on it. Note that this diver is not using the crotch strap, which is dangling below the tanks.

Bergaust, Erik and William Foss, Skin Divers in Action, G.P. Putnam's Sons, New York, 1965, page 35.

The set of tanks you have appears to be identical to the one in the photo. I peg this in the 1950s because this publication made extensive use of very old, at that time, US Navy photos (as they were public domain). Also, he is diving a dry suit, and a DA Aqualung (probably a BroXton), and the mask is a super-old Squale Mask (with the strap going into the band), available in the 1950s. I therefore have no compunction about copying them from this book (credit given) as it never was a copyrightable photo. Your set is very desirable, and should be able to be hydroed without problem.

The 1/2 inch tapered thread is not a problem, and is perhaps more reliable than the newer O-ring 3/4 inch thread. They are just harder to deal with. I just put a set of twin 42s into service with the first hydro since the 1970s, and 1/2 inch tapered threads without problems. You may have to tighten them, and they require the use of Teflon tape to make them seal. I had to re-tighten mine after assembly because they had a slight leak. It takes some muscle, but once sealed they are very reliable.

SeaRat

 

[Eric Sedletzky]

The military harness that you have was always sold with two bands. Here is a photo of a US Navy diver using a set of twin 72s in the 1950s with two bands on it. Note that this diver is not using the crotch strap, which is dangling below the tanks.

Bergaust, Erik and William Foss, Skin Divers in Action, G.P. Putnam's Sons, New York, 1965, page 35.

The set of tanks you have appears to be identical to the one in the photo. I peg this in the 1950s because this publication made extensive use of very old, at that time, US Navy photos (as they were public domain). Also, he is diving a dry suit, and a DA Aqualung (probably a BroXton), and the mask is a super-old Squale Mask (with the strap going into the band), available in the 1950s. I therefore have no compunction about copying them from this book (credit given) as it never was a copyrightable photo. Your set is very desirable, and should be able to be hydroed without problem.

The 1/2 inch tapered thread is not a problem, and is perhaps more reliable than the newer O-ring 3/4 inch thread. They are just harder to deal with. I just put a set of twin 42s into service with the first hydro since the 1970s, and 1/2 inch tapered threads without problems. You may have to tighten them, and they require the use of Teflon tape to make them seal. I had to re-tighten mine after assembly because they had a slight leak. It takes some muscle, but once sealed they are very reliable.

SeaRat

Hey John,
what did they use before teflon tape. I know teflon tape is fairly modern (late 70's?)
I thought they probably used pipe dope or something similar.
I saved that photo BTW and put it in with the rest of my stash of cool photos I'm collecting.

 

[Gilldiver]

I would also note that the hoses in the photo are a seamed single piece set.

 

[captain]

Hey John,
what did they use before teflon tape. I know teflon tape is fairly modern (late 70's?)
I thought they probably used pipe dope or something similar.
I saved that photo BTW and put it in with the rest of my stash of cool photos I'm collecting.

The same pipe dope that plumbers used on potable water piping.

 

[cool_hardware52]

I
The manifold uses 1/2" pipe thread with no O ring and it will take a large vise and the correct tool to avoid damaging it and likely a strong arm to remove it.

Probably not NPT (National Pipe Thread),

More likely NGT (National Gas Tight)

NGT share the same basic dimensions with NPT, but with less taper.

Tobin

 

[captain]

Probably not NPT (National Pipe Thread),

More likely NGT (National Gas Tight)

NGT share the same basic dimensions with NPT, but with less taper.

Tobin

Techically you may be right, in reality the same valve will be used in the same tank so it doesn't much matter.