I would be inclined to figure out the right fitting and adapt from there. Does the LP hose screw in and seat properly?... Just as a test fit of course.
Tapered HP port?
- Thread starter neonistic
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I would be inclined to figure out the right fitting and adapt from there. Does the LP hose screw in and seat properly?... Just as a test fit of course.
halocline
Contributor
Since the threads on the adapter obviously fit, just get a 3/8" HP hose and I bet it will work fine. Trident does sell them new I believe; if not, ebay.
You might get some knowledgeable opinions about this if you post on vintagedoublehose; they have a forum for vintage single hose regs.
You might get some knowledgeable opinions about this if you post on vintagedoublehose; they have a forum for vintage single hose regs.
oldmossback
Contributor
You could disassemble the 1st stage and take it to a small machine shop and have the machinest remill the taper into a flat so your hose fitting will fit flush. The milled brass should not show after with the hose end screwed down.........
halocline
Contributor
Now that's interesting, a regular 3/8" hose fits the threads but will not work because the recess bumps up against the outside of the hose fitting? I'd head over to the vintage forum and ask there. Obviously there was at some point a HP hose that fit this reg, someone's going to know about it. Luis H would be a good bet.
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
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
captain
Contributor
Sounds like it might work but I would be sure that with the washer there still a sufficent number of threads engaged.
If you get a washer and try it, put it in first without the O-ring, and tighten it down hard. Let the washer bend inwards to make a mating surface with the O-ring on the one side too. This is the way that the originals were designed, and they were a bit concave. It doesn't take much, and you should be able to get a seal. By the way, I looked and I do not have an extra washer or stem gauge.
SeaRat
SeaRat
OP
Well, I tried the washer with a 1500 psi tank and it held. I will try a full tank later and see if it holds that too. The trick is finding the right LP hose to get the washer to deform properly. I may try a socket and punch next time to get it right without putting stress on the 1st stage HP threads.
I just looked, and both my original Calypso regulators have the washer/O-ring configuration. Both are also in divable condition right now. When I do, I'll share them with you (probably over the weekend). But this works well to make the seal, and my SPG has no problems with thread engagement.
If the washer held at 1500 psig, it should hold at higher pressures. That regulator probably was designed for o 2475 psig tank, and most of these actually could withstand 3000 psig. So you probably don't need to do more about deformation of the washer. My feeling is that USD used a normal washer, and it simply deformed when it was tightened down. The taper is pretty small anyway. As I said above, I will post some photos of the washers that I have here.
SeaRat
If the washer held at 1500 psig, it should hold at higher pressures. That regulator probably was designed for o 2475 psig tank, and most of these actually could withstand 3000 psig. So you probably don't need to do more about deformation of the washer. My feeling is that USD used a normal washer, and it simply deformed when it was tightened down. The taper is pretty small anyway. As I said above, I will post some photos of the washers that I have here.
SeaRat
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