Royal/DA AquaMaster Differences

[admin]

This information may be common knowledge to many collectors but I'm sure some people may find out something new.
When the Royal Master came out in 1964, it was advertised with this opening line, "A balanced First Stage in the famous AquaMaster gives this "King of Professional Regulators" an even smoother performance under all possible demands". After rebuilding hundreds of Royals and DA AquaMasters, I've been able to note the differences between the two and other than cosmetics, the only differences are in the nozzle and nozzle parts. Because the Royal is balanced, (A "balanced" regulator "permits easy breathing and dependability to remain constant over all ranges of cylinder pressure..."), it has a larger spring block with a spring on either side and this requires a longer nozzle to hold these extra parts.
The Royal was also advertised as having a , "Larger orifice for better flow at depth". It took me a while to find this "larger orifice" but I finally discovered that the nozzle "volcano" orifice is .110 inch, while the late model DA AquaMaster is .092 inch (it's interesting to note that the older dull chrome AquaMaster nozzles are even smaller at .080 inch). The nozzles are interchangeable between the Royal and DA AquaMaster because everything else on these regulators is identical. More than once I've purchased a "Royal" AquaMaster only to find out that it was a plain AquaMaster with a Royal label. But there is an easy way to tell the difference without disassembling the nozzle. Because the Royal nozzle is taller by about 3/16 of an inch, there is more play in the yolk on the Royal and it will move up and down about an 1/8 of an inch where as the AquaMaster yolk only has about 1/32 inch up and down travel (see photos).
You can upgrade the high pressure seat in your Royal by using one from a newer Conshelf/Titan single hose regulator. This new seat is Teflon (as opposed to the Royal's rubber seat) and it will last longer and withstand higher tank pressures. When using this new seat, you will also have to replace the original push pin (1046-18) with a longer one of the correct length. The nozzle springs should also be replaced since the originals tend to get weak with age and can cause a free flow with 3000 psi tank pressures.

[caveman]

Thank you for that info, NOW I know that I have a genuine Royal. I always wanted to know for sure. By the way, the 1960 Healthways you show in your online museum is mine...

Caveman

[crimediver]

Thanks for the handy reference. I have also seen one Royal that was bogus. Not sure if this was done deliberately or someone rebuilding one using parts from a DA or replaces a boxtop.
This will help keep people from possibly getting burned.

[robohips77]

Dan, Well written, Thanks for the pictures as they are worth a thousand words. I have a friend who has questioned his round label and now he will know. Robohips77

[Broxton Coalition]

Thanks Dan for posting this info. i am wondering if you could post some close up pictures of the high pressure seat. old and worn factory seat and a new conshelf seat. i think it is good advice about upgrading to a conshelf HP seat.
when traveling with a RAM it would be nice to know that wherever i travel to, and believe me i am thinking about traveling this weekend(-18 last night) i wouldn't think twice about 3000 psi.
thanks Dan,
mike

[luis]

Dan
Those are great pictures.


Back in the 70’s I converted my round label Royal to an Aqua Master because I got tired of the soft first stage seat leaking. Two years ago I bought a 1st stage RAM nozzle to convert it back to its original configuration. It is great having my RAM back as it was, but I can understand how a Royal could have ended up with a DA first stage. The old DA seats (in the 70’s) were much more reliable that the RAM seats of the time.

The newer Aqua Lung Teflon seats are just great. They are far superior to the 1970's hard rubber seats.



IMHO they are not Conshelf seats. The seats were first used on the RAM and when the Conshelf was introduced it was advertised as having the same great first stage as the RAM.
The Teflon upgraded seat is a replacement part meant to be used on all US Divers diaphragm first stages that have followed the same (or similar) design as the RAM; it includes the Conshelf, the Titan, the Legend, and several others. Therefore, IMHO since they were design for the RAM and its successors, they are technically RAM seats.




Added:

The high availability of highly reliable RAM parts is what influenced me into designing the replacement RAM first stage (the Phoenix) with the replaceable volcano orifice used in some of the newer Aqua Lung regulators.

The original idea behind the Phoenix was to extend the useful life of so many Aqua Masters that are in existence. Replacement first stage seats are not available for the Aqua Master, but the Royal Aqua Master will probably have replacement parts for as long as Aqua Lung is in business.

[admin]

You are correct Luis, as far as the first stage and seat design began with the Royal AquaMaster. But I just refer to the new replacement Teflon seats as "Conshelf" seats to avoid confusion. Here are some photos of the new repalcement seat and the original Royal seat. You have to use the correct pin length when using the new seats.

[nemrod]

Is the overall length of the assembly -- with pin inserted --- from the tip of the pin to the end of the seat the same length? Is the amount of pin protruding from the seat the same length?

Nice pics, thanks, this will be very helpful to new buyers.

I have several new NOS RAM seats and it is true that the new Conshelf/Titan style is far superior and in my opinion they set up easier and breath slightly better because they are more stable--you can tune the regulator to a finer degree and still have a stable acting regulator from day to day.

The Conshelf/Titan seats are key to using high IP (140 -160 psi) in the RAM. I don't think I have ever said that exactly but I think NOS seats are not up to the task.

James

[luis]

Nice pictures

nemrod said:

Is the overall length of the assembly -- with pin inserted --- from the tip of the pin to the end of the seat the same length? Is the amount of pin protruding from the seat the same length?

Yes and yes

nemrod said:

Nice pics, thanks, this will be very helpful to new buyers.

I have several new NOS RAM seats and it is true that the new Conshelf/Titan style is far superior and in my opinion they set up easier and breath slightly better because they are more stable--you can tune the regulator to a finer degree and still have a stable acting regulator from day to day.

The Conshelf/Titan seats are key to using high IP (140 -160 psi) in the RAM. I don't think I have ever said that exactly but I think NOS seats are not up to the task.

James

Like I mentioned before, I was so fed-up with the old seats leaking, I converted my RAM to a Aqua Master in the 70's.

I agree, the new Aqua Lung Teflon replacement seats are awesome!

[Broxton Carol]

Whats all the snorting about the new teflon seats? I still have the original 42 year old hp seat in my Royal and it works perfect, breathes perfect no complaints. I even have the original 1954 seat in my BROXTON and it dosent leak. breathes great works perfect etc..... Hp seats rarely ever go bad. I did have ONE mistral seat get impacted, because a guy who sent the reg to me for overhaul said he put it on a 3000 psi tank. That may have caused failure. But when I overhauled a reg, rarely was a hp seat any problem at all. All that ever wears out are the soft rubber parts. If your going to use a 3000 psi tank then your moving your reg beyond the design limits It was made to. If your going to change things around and use a 3000 psi tank with a 2 hoser, thats the risk you run. Your not vintage anymore anyway. Thats like putting a 327 engine in your 57 chevy. It never came with it, so you dont need it. Keep your money in your pocket. If you ever DO need a seat, and you likely NEVER will, then replace with whats available.

[luis]

The hard HP seats on the non-balanced regulators like the Aqua Master have always been reliable. I think they were made of hard nylon and the tank pressure helps them seat.


For the balanced Royal Aqua Master they originally used a rubber compound. I believe the idea was that since the tank pressure does not push the seat closed (due to the balancing chamber with LP air behind the seat stem) they could get away with the softer compound. My observations were that the rubber would take too much of a set and it was very unreliable.


Chuck
I am glad to hear that you have had good luck with the original Royal Aqua Master rubber seat. My experience with the early RAM / Conshelf seats was pretty bad.

The original seat on my round label RAM lasted probably over a year. When it started leaking I ended up replacing it several times. Sometimes worked for a wile and then will start leaking.

I worked at a dive shop in the 70’s so I had access to as many seats as I needed. We might have had a particularly bad batch of seats, but we had a small drawer full of seats and once I tried it I had to throw it away. They immediately took a set.
The bottom line is that I even tried a new first stage nozzle and that only solved the leak for a short wile.

We were mostly a Scubapro dealer, so I didn’t have to deal with too many Conshelf at the time. My buddy and I were the only two divers I knew that were still using double hose regulator (on occasion).

[Broxton Carol]

Luis, thats a great observation. I never thought to notice that the aquamaster seats are a different material. All I remember is the royal seats were the black plastic loking stuff. Not like a hard rubber lp seat, but a shiny vinyl like stuff. My seat still seals perfect, but then I NEVER hooked it to 3000 psi except one time, when I bought a pair of shorty doubles!! I hurt my back then, and couldnt lift them. Anyhow, I have replaced lp seats for other guys, but out of say 25 regs, only 2 needed seats replaced, so I sold all my aquamaster seats to guys who thought they needed them, or thought they needed a spare. They likely still have them ha ha. I have seen many grooved mistral seats, but somehow they still seal good. I have one aquamaster seat in reserve for my broxton, or navy type da. The tanks I use with those are rated at 2150psi. Some of the guys have seen me with them. Dont laugh they still get the job done! My other cylinders are always pumped to 2500 psi, and I have never had any trouble with any regulator I ever hung on them.

[Michel]

Hi guys(and girls),
Great discussion as I have also bought a RAM which turned out to be an AM,got caught only once but it turned out well because this round label now breaths better than my square label Royal! I also agree with Chuck as many of my very old am's still have original seats and work superbly,what can go easily is the rubber lp seat in my experience which is an easy fix. On another matter re:RAMs,since it seems that one person is responsible for buying every/all big knob Rams on the planet does anyone know if the big yoke/knob can be cannibalized from readily available single hose 1st stages(u.s. divers) to up grade a round label RAM which does not have it? I can't seem to get my hands on a last of run production big knob RAM with clamp ring without selling my gold Submariner! Thanks to all,Michel A.

[nemrod]

BTW, the last heavy yoke RAMs say 3,000 psi on them from the factory.

I am not sure but the yoke from a Tekna/Oceanic clone MarkV might work, I will research that this weekend. You should be able to adapt a yoke from another regulator and Dan does occasionally sell a very nice converted super heavy Dacor yoke.

It is interesting that several people have recently purchased Royals Aqua Masters only to find they are DAs. Strange thing that is. Dan's pictures should help people identify these imposters.

You will never get a NOS seat to set up and behave at pressures much beyond 140 psi. I have experimented as high as 180. There are other limitation and I have dropped my pressures back to 140 plus or minus a touch mostly because of desired compatibility with the octapus seconds I have at my disposal and my wish to keep my gear modular. Note, once much above 150 psi it takes a careful touch and the RAM regulaotrs become prone to free flow/after flow. I accept a certain amount of free flow or bubbling (bubble--------bubble------------------------bubble) in certain postions in order to achieve minimum cracking force---others may not like that. Thing is, with the NOS seats I cannot get a stable set up and with the Titan seats the regulator becomes stable and remains consistent day to day and month to month. With the NOS seats, I would set it up and then a few days later or at depth it would free flow. Readjust it--good---then again a few dives down the road--free flow again. The Titan seats do not act this way. Super tuning your RAM requires the Titan seats--IMO.

James

[Michel]

Nemrod, very interesting.

I like to keep my regs 'original as possible' so other yokes will not do,
however in the 1970's USD certainly did not design a heavy yoke just for the RAM as this would have increased cost so there must be a yoke from another model USD(probably single hose) that is identical/interchangeable, I am trying to find out. As far as the RAM seats go my original '66 RAM works fine probably because it is tuned to USD specs.(ie 100-110psi) NOT 140psi+!!!!Remember the old manuals and the veterans would say 'do not adjust to make breathing too easy!).When I get my hands on a late model RAM I will switch to the Teflon as I agree it is a superior seat but until then I have plenty of NOS RAM seats and 2 NOS AM seats(secret source)as spares.Michel A.