The Aqualung Mentor (Photos etc. . .)

[sea.explorer]

Look what showed up in the mail yesterday ;D



The serial number is 0022/02. I will be taking better images inside and out as well as photos of the Mentor alongside the New Mistral, The Phoenix RAM and a stock Royal AM for comparison. I will also be reporting on the diving performance and hopefully some new info on its development. Notice the cool logo with the double hose and double tank. The pictures don't do it justice. It is a beautiful Reg. You can see multiple large images at www.flashbackscuba.com just click on the Museum link. I also posted some great Cousteau Equipment images by David Haas from the Sand Dog Event. Enjoy.

-Ryan

[shackle]

Great pictures Ryan, of both the Mentor and the Sand Dog event. Can't wait to see the comparison photos.
Scott

[Creed]

So, how much did that puppy run you?

[JES]

Ryan,

Awesome regulator! It looks like it was built to be bullet-proof.

We're green with envy.

Without question, I'm sure that everyone is looking forward to your report. ;D

[sea.explorer]

I put together a new update with much better images and more information:

www.flashbackscuba.com/museum/New_Museum.html

I hooked the reg to a tank and it breathes effortlessly. The balanced second stage makes a big difference. The diaphragm is virtually identical to the ones at VDH. The only noticeable difference is that the flange is thinner. It uses a diaphragm without tabs like the original Mistral.

I can't wait to get it in the water. The hoses are similar to the New Mistral but they are made of heavier rubber not silicone. It is a fine piece of hardware! As for the question of price, getting a Mentor had much more to do with networking than $. The reg came from a person who worked on the development of the regulator. Aqualung does not have any in stock and the timing of a new run is unknown. There are no intentions of selling the Mentor to the public. Sorry to dash people's hopes but this information is current as of today and comes from the source

-Ryan

[luis]

rndboulder said:

I put together a new update with much better images and more information:

www.flashbackscuba.com/museum/New_Museum.html

I hooked the reg to a tank and it breathes effortlessly. The balanced second stage makes a big difference. The diaphragm is virtually identical to the ones at VDH. The only noticeable difference is that the flange is thinner. It uses a diaphragm without tabs like the original Mistral.

I can't wait to get it in the water. The hoses are similar to the New Mistral but they are made of heavier rubber not silicone. It is a fine piece of hardware! As for the question of price, getting a Mentor had much more to do with networking than $. The reg came from a person who worked on the development of the regulator. Aqualung does not have any in stock and the timing of a new run is unknown. There are no intentions of selling the Mentor to the public. Sorry to dash people's hopes but this information is current as of today and comes from the source

-Ryan

Hi Ryan

That looks great.

Great pictures. Thanks

Looking at the diagrams of the Mentor (and your inside pictures), the second stage looks like a very well design, but conventional down stream demand valve (not a pneumatically balanced demand valve). Am I seeing something wrong?

Can you check what is the dimension form the tank connection to the front of the can (how deep)? As in how much does it stick out from the tank valve interface?
How does it compare to the Phoenix?

Thanks

Have fun.

Edit:
Another question. The horns/ hose connections on the regulator look to be 1 inch like our vintage hose horns (not like the new Mistral), is that correct?

[sea.explorer]

Luis,

The horns are the same size as the vintage regs. The second stage is balanced and had an external adjustment that allows you to balance the second stage. You can see the adjustment mechanism here:

www.flashbackscuba.com/museum/Aqualung%20Mentor/Aqualung%20Mentor-Pages/Image8.html

It is to the right of the intake. The depth of the regulator is the same as the Phoenix. Out of the water it is the easiest breathing regulator I have used. The main reasons I think it performs so well: High performance silicone diaphragm, high performance mushroom valves in the mouthpiece and the exhaust , and the balanced second stage. We are talking a very small but noticeable improvement in performance over the Phoenix based on my initial impressions. That being said it is very comparable to the Phoenix.

-Ryan

[nemrod]

It seems like the main improvements of the Mentor are the large "rebreather type" mouthpiece with larger silicone valves, silicone valve instead of duckbill and possible balanced second stage.

That is a pretty regulator, I like the dome cover with central exhaust VALVE!

I find it interesting how similar it is to the Phoenix in dimensions, especially length of assembly from valve face.

I also like the non critical horsehoe. The "roller" tabs are on the horseshoe and not on the diaphram preventing ceitical misalignment of the diaphram and horsehoe--nice.

That said, I think there is more perfomance to be had in the old girl (RAM), we just haven't figured it all out quite yet how to get it cost effectively, DSV valves cost a fortune. That and a valve exhaust may represent the final frontier.


James

[Captain]

I would have thought the mushroom exhaust valve would have been bigger.

[luis]

Hi Ryan

The mentor is definitely a beautiful regulator. Since only130 were built, I would say that they were not only hand built, they were hand crafted.

The second stage looks great. It resembles in many ways the second stage on the Voit Trieste. The major advantage over the Trieste is that this one has an adjustable (and replaceable volcano orifice). The adjustment for the volcano orifice is what you are seeing from the back.

The second stage is not what I would call a pneumatically balanced second stage. Not that my definitions are universal, but a pneumatically balanced second stage would incorporate a pneumatic chamber on the downstream side of the seat carrier to balance the IP pneumatic force. The chamber becomes kind of a pneumatic spring and therefore the closing spring can then be extremely weak and still close the demand valve.

There are several different geometries that accomplish the same effect, but the basic idea is that the moving parts are not affected by air pressure. You don’t actually want to make a 100% balanced second stage or it will loose its pressure relive safety backup.

The Mentor has an adjustable volcano orifice which facilitates the adjustments. Having easy adjustment of the second, allows you to more precisely balance the IP force with the spring force. This is what I like to call manually/ mechanically balancing the opposing forces on the demand valve.

Mechanically balancing the forces in the demand valve is by no means automatic and can be accomplished to some degree on most respectable second stages (definitely including the RAM), as long as the first stage IP is constant. The mechanically balanced forces can deteriorate with time as the second stage seat forms a grove.

In the case of the RAM you don’t have an adjustable volcano orifice, but backing the spring retainer accomplishes very crudely some of the same effects. The final adjustment has to be done by changing the IP, were in the Mentor adjusting the orifice will adjust the second stage spring tension.

The pictures of the Mentor show what looks like a very effective venturi flow geometry. As opposed to the new Mistral, which probably has one of the most poorly design air flow paths I have seen. When you look at the new Mistral the demand valve shoots the air against the side of the case not the inlet hose, basically destroying the possibility of any venturi effect.

The venturi in the Mentor again resembles the Voit Trieste, but the venturi alignment of the Mentor seams more precise than most any double hose I have seen. That is a major advantage of hand crafting what is already s good engineered design.

Improving mouthpiece valves IMHO is the major next leap in performance for our aging RAM’s (and now Phoenix RAM’s). I tested the new Mistral mouthpiece with one of my Phoenix RAM’s and the performance was phenomenal. You should try the Mentor mouthpiece and hoses on your Phoenix. It may be that a lot of the improved performance comes from reduced mouthpiece valves flow resistance.

I also find it very interesting that the size of the Mentor resembles the Phoenix Royal Aqua Master.


Thanks for all the info.

Looking forward to your reports.

[sea.explorer]

Luis,

Again we find ourselves discussing the definition of "balanced". We both know that it is a term used to describe very different things by different companies. You are right that you are balancing the spring tension against the IP on the mentor and there is not a balanced chamber on the second stage. The difference in my mind is that when you are dealing with the second stage you have a constant pressure effecting the mechanics. Since this is a constant, unlike in the first stage, mechanically balancing the spring pressure is all you need to adjust performance of the valve one way or the other. It is a simple solution that produces good results. It is ultimately a different solution to achieve the same end.

Finally your comparison of the Mentor to the Trieste is appropriate. The Mentor borrows many of the best features from the RAM, The Trieste, and The Snarks (Mushroom exhaust) and puts them together in an efficient way. I like the fact that the adjustment of the second stage doesn't require disassembly of the reg. I also think you are right about the mouthpiece and mushroom valves playing a significant role in the ease of breathing. The mouthpiece valves on the Mentor are 1.25" in diameter. There is little doubt that the P-RAM will benefit from the mouthpiece on the Mentor.

The mentor is crafted to the tightest tolerances of any reg I have seen. It is a real work of art that was made possible by the high cost and low production numbers. When thinking about the cost it is important to consider that they are only sold directly from the manufacture which puts an additional 40% margin usually reserved for the retailer back in the the production costs. This is a very expensive endeavor to produce. If they were to release the reg to the public it would likely retail in the neighborhood of $1700 to cover shop margins.

Tom,
I too was initially surprised that the exhaust valve is as small as it is, but I think there is little advantage to making the exhaust larger than the mouthpiece valve since the mouthpiece valve becomes be the limiting factor.
-Ryan

[nemrod]

How does hose routing work out with the Mentor. One of the things I like aboutmy phoenix is how easily I can perfectly route my hoses for BC, spg, octapus, SeaTurtle etc. I also like the archaic hookah port converted using a Moss type adapter.

I think the mouthpiece and larger cage valves are the key to making the Phoenix breathing effort on par with the Mentor.

James

[SeaRat]

Ryan,

I think that if they made the mushroom exhaust in the top box bigger, it would free-flow pretty badly in certain positions. It probably does not need to be as large because of its positioning above the lungs in most diving scenarios, which gives it a natural ease of breathing out because of the lessened water pressure (which also increases the inhalation resistance due only to water pressure of a two-hose regulator on the tank).

Now, I've got my Trieste II completely disassembled, and need to clean it up and reassemble it, or I'll miss out on the summer's diving!

John

[nemrod]

Is the Mentor case stamped or machined from billet or a casting? I assume it is brass?

James

[luis]

The cans look to me like they were stamped. Specially the exhaust side. Ryan will have to confirm this.

The main body looks like it was machined from a solid block. When I talked to Ryan he agreed that it looked like a machined piece.


Ryan
Do you know when (what year) were the Mentors made?

I also wonder how many pare parts did they make (hoses, mouth pieces, etc.)?