Question UDS-1 triple tank NOS in original box

[Malibu mike]

Looks like I can’t post in the classifieds because I’m a new member so for now I’m just going to ask peoples opinion if they think this might’ve been a floor model back in the day.

I purchased it at an estate sale and it came in the original box. The original inspection tags and an instruction how to use the mouthpiece were still attached to the regulator. Everything about it says it was never used, but there are some very minor scuffs that make me think it might’ve been used as a floor model to show people what they could order. Glad to hear anyone’s advice about how unique this piece of driving history is.

 

[jadairiii]

Pretty unique. This was marketed back when just about every manufacturer was coming out with a "streamlined" system. First was the Water Gill At-Pac, Scubapro followed close behind with the Scubasystem, Dacor had the Nautilus. There were a few others and some companies that made a shell to fit any rig.

USD came out with this, making it close to what Cousteau was using. What was really unique was the reg 1st stage was incorporated into the tank valve "system" and it had a fitting to fill it, since you couldnt take off the first stage. Not 100% sure, but I understand that valve/1st stage can be tough to rebuild. Everything else is standard USD.

What killed it was it was overly complicated, only held 90 cuft (so you needed a compressor on your boat or at the beach if you wanted to do a second dive) and it had no built-in buoyancy compensator, like the other "systems" did. But USD did follow it up with a less complicated triple tank system in a shell with an attached vest.

If this is the same one on ebay, it does look like it was used based on how scratched up the second stage is, probably just in a pool or lake. But awesome that you have the box and it is pretty much untouched. The shell looks perfect!

 

[USdiver1]

Unique indeed. This is true of all aspects of the USD-1 system, including the three aluminum cylinders. Due to the alloy used in their construction, I do not believe that they will pass current hydro inspections. If you do decide to have them hydro-tested, check with the shop doing the work beforehand, and that they will not, repeat not, drill our the tanks if they fail. That could ruin their collectibility.

Very nice find BTW.

 

[iain/hsm]

To be frank the biggest issue is the scuba hydro test houses in that they do not have the correct adaptor to connect the hydro test rig to the USD-1 cylinder threads and cannot therefore test correctly.
Further more neither do they have the correct Go-No Go thread gauges with which to check the threads.

The standard thread on an American DOT scuba cylinder is a sharp 60° flank angle thread called 3/4" NPSM

However the thread on the USD-1 DOT cylinders is a huge Inch and a quarter diameter
1.250-12 TPI and UNF form to class 2B

Which incidentally is a much better thread and unlikely to be affected to sustained load cracking
as with the Royal Navy design using a 1-1/8 by 12TPI UNF 2B thread for their cylinders.

Your USD-1 is a unique work of diving engineering of which I only know of two that are new unused.
Neither are they for sale, yet as it will be up to a younger generation to flip them for a pair of gym shoes.

I will try and dig out the drawings and sales bumf of this if I get time. Iain