Vintage Double Hose

Awesomeo 5000

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How many guys on the forum have one of these? Im curious as to how rare they are.

I know Allan, Karl, and Tom have one. They are definitely rare though. Before the bottom fell out of this stuff they went for 800 bucks back in 2008-2009. I will tell you that getting one for 300 dollars was totally unheard of a few years ago. Even DX Overpressures in complete condition were going for 700-800 back then. I had to pay quite a bit for mine and now they sit on Ebay all day at 400 and nobody buys them. I would gather that we have finally reached market saturation in the vintage dive gear world.

Herman has not updated his adventures with them in a while...

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With SeaHunt and personal life I have not get back to the ...soon.

I thought I was on to something with these, but I was wrong.

The Cow has 3 Royal Mistrals 2 have a very slight leak,very rare!

Keith are those seats that you made or pre-existing ones that you came across?

We use these at work on our refrigerant and helium tank valves. Dont know what they are made of but I can send some to anybody that wants to experiment.

I'll experiment with some. Send me some and I will see if they work.

OK so Im going to make a couple brass seat holders with replaceable Delrin soft seat. It should hold up because the only pressure on the delrin will be the poppet, so about 145 psi or so. We'll see how it turns out.

Let me know man. I'm in to test, chip in on materials, test dive, etc.

Looking more closely at mine, the soft seat material kind of looks like an oring pressed into a pocket on the seat holder/retainer. Mine is chunked out so it'll never seal but maybe this material was made to be replaceable.

Mine looks just like yours except the seat material is good on mine. See if you can get the soft seat material out. If we could make just the new soft seat and use the old part around it that would probably be even cheaper. If we can make these cheaply enough we can make sure that all of us with RMs could use them, which would be a huge boost for all of us. That material must have been brittle from the factory, because lots of the leaky ones look just like yours.

Life has gotten in the way of my shop time recently but that is getting much better now so once I catch up with my tools, I can get back on this. Here are some of the issues I have found,
The material in the metal part of the original seat is molded in. Removing it is going to be a bear short of using a solvent to dissolve it but more to the point, you can't just press something back in. The new "insert" will have to be either molded back in, sealed with an oring or glued/bonded in some way, otherwise you will never get it to seal, it IS going to leak. Cost wise, this would be a much more expensive option plus you would have to find a number of seats to convert.
Making a one piece seat in some material like nylon is going to be the best bet. I need to experiment more but so far delrin seems to be too hard for this application and Teflon is too soft....I had a Teflon seat extrude under pressure. I have has some success with nylon....I did a lot of seat experimenting a while back so I have those materials on hand. The 2 issues I am having are getting a good seal and balancing. I have no idea what the actual amount of balancing was in the original so I may be getting "normal" results. Looking at the geometry of the seat it does not appear that it would be as balanced as a standard USD seat. As it turned out, a lot (most ??) of my sealing issues were due to the hard seat stem. At least on the one I have, it is a good bit smaller than a normal USD HP seat stem and under the proper diameter to seal with the standard Orings used in USD balance chambers. I doubled up the orings and that seemed to "fix" the problem but I am beginning to believe that many of the sealing issues with these regs was not the seat but rather the balance chamber oring to seat interface.....unless you know what to look for, determining which is the issue is difficult. To get a reliable seal different orings are going to be needed.....I am wondering if the originals were actually metric....another thing I need to look into.
The next question is what the goal here is? Restore it to original with repro parts or just get it diving again. Restoring it is going to be a little difficult and expensive to do. With the limited number of regs and even more limited the number of folks wanting to restore one, the cost will be high. If on the other hand, if getting it back into diving condition is the goal, I think there is a better approach. Install standard USD/AL HP hard and soft seats and designing/ making a new pin. A replacement pin is a lot easier to manufacture and a lot cheaper. A simple kit could easily be made for the conversion and from then on, service will be easy. I am pretty sure this approach will work but again, it would have to be looked at closely to make sure the dimensions are correct....off hand I do not recall the diameter of the original seat. Even if the standard hard seat is not the correct diameter, a slightly different sized version of would be a lot easier to produce than an original style one.