tapered HP port?

[neonistic]

I was told to try here for an answer to my problem. I have a us divers conshelf first stage that had a taper going into the HP
port. Because or this I cannot use any modern 3/8s HP hose or adapter as it hits the shoulder before getting tight enough to seal.


See this thread for pics and more info.

http://www.scubaboard.com/forums/regulators/331762-tapered-hp-port-2.html

 

[captain]

I followed your other thread but didn't comment because I really don't have an answer. I am familiar with the Conshelf VI but do not recall any in that configuration. How did you come to own it.
That a stock regulator was factory modified for a particular use is not out of the question or that an individual modified it for a particular reason is possible but the lack of missing chrome tends to support a factory modification.

 

[neonistic]

I got it with three tanks from a diver who is no longer able to dive.

 

[knowone]

Fat O ring.

 

[captain]

I got it with three tanks from a diver who is no longer able to dive.

Maybe you should ask him.

 

[neonistic]

He had it hooked up to a 3/8's HP hose that was cranked down really tight. When I put that hose on after the rebuild it wouldn't seal.

 

[oldmossback]

disassemble it, and have the tapered unthreaded part milled down to a flat surface.........a standard hose connection will work then. Lord knows what that taper is for.......you might spend years searching for the correct hose connection.

 

[captain]

It can't be milled completely flat as some taper or counter sink is required to capture the O ring and prevent extrusion.

 

[neonistic]

If I milled down most of the taper it would remove roughly 2mm of material from the 1st stage over a 2cm x 2.5cm area. Wouldn't this weaken the housing? I really would prefer to find the correct adapter or o-ring needed so I don't have to modify the reg. I have thought of just putting a 3/8's plug in the port and just checking the pressure prior to the dive. This is only going to be used for my pony bottle as of right now.

 

[John C. Ratliff]

I think I may have an answer for you, Neonistic. The first Calypso regulators came out with this type of opening, and it was from the factory. The Conshelf must have come out just after that, before USD standardized on a HP thread type. What they had was a stem gauge in the HP port, as at that time the regulators did not use gauges on hoses much (a single hose regulator was a "single" hose regulator). That stem gauge was equipped with a washer that fit between the gauge and the O-ring. So, get a stainless steel washer with the opening for the fitting, and put an O-ring behind it. I know, as I have two Calypso regulators, and one still has the original stem gauge on it, with this type of opening.

Or, go to a LDS and ask to see all their old HP & LP plugs. Look for a weird one with both a washer and a metal protrusion that has a opening (for a stem) in it. This is the original stem gauge that went into that kind of opening. Also, I'll look and see if I have an old one in my dive tool box--don't think so, but it's worth a look. Maybe one of the vintage divers has one laying around too.

One of these two methods should allow you to use the current gauge you have with this opening--fitting a washer to fit between the O-ring and the body of the fitting to give you a sealing surface on both sides. I'll try to get a photo later, but I've had to redo my computer after a crash and don't have all the software set up yet. In any case, I'd do this before trying anything drastic like milling the regulator. I have a pressure gauge on my other Calypso, and I believe I did that to it with the washer.

SeaRat