Royal Aquamaster: how much PSI is too much?

[herman]

It was a fun bunch, that is me hiding behind Anna (center of photo). Sorry for the hijack, as you can tell, there are still a lot of the old regs in service.

 

[WD8CDH]

Actually, if you are using a valve with the small skinny o-ring (like the Sherwood 4000 or 5000 series valves) at 3000psi, you will have about the same force on the yoke as a fat o-ring valve at 2450psi.

 

[Slonda828]

My heavy yoke RAMs have seen pressures of 3,500 psi. If you have the standard duty yoke I would keep it to less than 3,000.

The HP seat used in the current Titan/Conshelf is a perfect fit for the RAM since the first stage is essentially the same first stage. You should have no problem with 3,000 psi tanks with the RAM or for that matter a DA.

BTW, the 7.0 inch diameter Faber LP 85 is a great tank.

During the Bahamas SD event we were gathering on the dock, a couple of us wondered why the crew was letting air out of the tanks. We asked and they were dumping the 80s down to 2,200 psi because they had heard we could not dive with 3,000 psi. We freaked and told them to pump those suckers up till they swell. So they did. This idea that a double hose cannot operate at 3,000 psi is plain wrong. In fact, not only did we dive twin stage at 3,000 but we dove single stage like the Mistral and 50 Fathom at a full 3,000 plus.

N

I just wanted to affirm what Nem said. I dive both single stage and two stage double hose regulators on 3,000 PSI tanks. The softer HP seats (DA aquamaster and Mistral) will wear f aster, but who cares, you can surface them forever. I have also used 2250 service pressure yokes on 3,000 psi tanks with no issues, and all my yokes are original and probably 40 years old.

BTW I miss diving with you guys already. We need to go someplace else exotic and hang out again. I dove a drysuit today with a tech setup and I really missed my vintage gear. We just wear SO much crap in modern diving.

 

[DCBC]

Great post! I started SCUBA with a single stage 2 hose Healthways. The Aquamaster was the first reg that I purchased in 1965, I think that 3000 psi is the maximum pressure you would want to subject it to. I started getting free-flow with the first aluminum tanks that came out, no matter how much I tinkered with the P2 settings. Perhaps it was because I had an older model. Anyway, my 2 cents worth...

 

[jcarpini]

great photos I love it!! Thanks for your response. Well I have a very nice DA Aquamaster and a Jet air, and I was thinking that I needed to get a royal Aquamaster or a phenox to handle a higher Pressure Sounds like both my regs can handle 3000 PSi. what about the HP seat in the jet air ? Aloha and thanks again

 

[Slonda828]

J,

Any of the single stage USD double hose regulators (jet air, mistral, stream air, overpressure breathing) have the same seat. They can be refinished if you have patience and some 2,000 grit sand paper. I average about 50 3,000 PSI dives before a resurface, but I am anal. I have never had one of my regulators creep after a rebuild. The unbalanced two stage regs (think DA aquamaster) can also be refinished in the same fashion. I use those all the time on 3,000 PSI as well. The RAM is fully balanced, and therefore the seat is not directly subjected to high tank pressures like the unbalanced regs are. I have never once had an issue. Also, don't forget to visit Vintage Double Hose and look into joining our organization, the NAVED.

 

[Luis H]

New reproduction seats for the single stage Mistral (or Jet Air, etc.) are also available from VDH. Personally I don’t resurface seats if replacements are available, but I also don’t dive a Mistral that often and never with 3000 psi tanks. I mostly dive steel 72’s.

The only times that I use 3000 psi tanks is when I am renting down in the Caribbean and then I only use one of my Phoenix RAM.

Using a Mistral or Jet Air with 3000 psi will also make it breathe that much harder. They breathe better as the tank pressure is going down.


As mentioned above, the extra pressure will put some extra wear on an unbalanced seat, but it is probably not as bad on the DA Aqua Master.

The load on the yoke is not too bad as long as you don’t exceed 3000 psi. It will not break it, but you do need to tight it firmly to avoid an O-ring extrusion.

 

[halocline]

J,

The RAM is fully balanced, and therefore the seat is not directly subjected to high tank pressures like the unbalanced regs are.

As mentioned above, the extra pressure will put some extra wear on an unbalanced seat, but it is probably not as bad on the DA Aqua Master.

I don't know about this; it's IP that closes the seat. Sure there is some increased force on the seat from supply, but IP lowers in response to this. The only way that there would be increased pressure on the seat would be if the increase in supply pressure acting on the seat was greater than the decrease in IP associated with higher tank pressure. I have a pretty strong feeling that the total seating force is just about the same, until supply pressure reaches the point at which the seat cannot maintain a good seal and IP starts creeping.

 

[Luis H]

I don't know about this; it's IP that closes the seat. Sure there is some increased force on the seat from supply, but IP lowers in response to this.

Actually, the IP allows the seat to close by pushing on the diaphragm and moving the pin away from the seat. The pin doesn’t pull the seat.

See post number 9 on this thread:
http://www.scubaboard.com/forums/vintage-equipment-diving/302511-da-aquamaster-3000-psi.html

The only way that there would be increased pressure on the seat would be if the increase in supply pressure acting on the seat was greater than the decrease in IP associated with higher tank pressure. I have a pretty strong feeling that the total seating force is just about the same, until supply pressure reaches the point at which the seat cannot maintain a good seal and IP starts creeping.

Yeah... that is kind of what happens.
Again, I hope my other post is helpful.

 

[Paladin]

Not to hijack this thread, but I was just wondering about this Phoenix nozzle I've been reading about. Is it still available and does it work on A DA Aquamaster?