Proton adj.

[maxmaxum]

Is there any difference in the adjustment of a Mares Metal Proton octo and a Regular Mares Metal Proton second stage reg. I have both and both are going to be used as octos. My concern is free flow from the proton that was not originaly an octo. If it does require adj can it be make in the field?

 

[LeadTurn_SD]

If you have the correct tools and understand what you are doing, they can be fairly quickly tuned in the field (detuned slighty, that is).

It would be far better to check their cracking pressure relative to the IP of the first stage you will be using them with, and adjust them to that 1st stage before diving with them.

The Protons we have are all set up as primaries, and I tune them to about 1.2 - 1.3 inches cracking pressure. I have not set one up as an octo, but I'd probably detune just a tad from that level.

You may want to send a PM to Greg Barlow (he dives the Proton Metal, has worked on Mares regs for years) to get his input on how much to detune the Protons for use as an octo.... my personal bias would be to not detune them very much, as they are pretty "stable" as long as you handle them properly (not overly sensitive to freeflow; but they will freeflow on the surface if handled improperly).

Best wishes.

 

[Greg Barlow]

If you have the correct tools and understand what you are doing, they can be fairly quickly tuned in the field (detuned slighty, that is).

It would be far better to check their cracking pressure relative to the IP of the first stage you will be using them with, and adjust them to that 1st stage before diving with them.

The Protons we have are all set up as primaries, and I tune them to about 1.2 - 1.3 inches cracking pressure. I have not set one up as an octo, but I'd probably detune just a tad from that level.

You may want to send a PM to Greg Barlow (he dives the Proton Metal, has worked on Mares regs for years) to get his input on how much to detune the Protons for use as an octo.... my personal bias would be to not detune them very much, as they are pretty "stable" as long as you handle them properly (not overly sensitive to freeflow; but they will freeflow on the surface if handled improperly).

Best wishes.

I agree with your answer. With my own personal Proton regs I adjust my primary to 1.1", and the back-up to 1.3". On customers' regs, I go with 1.2" and 1.4".

Contrary to a common rumor, Mares does not use different lever springs in the AAS versions. They use the settings that I adhere to.

Greg

 

[maxmaxum]

Excellent advice, thanks to u both. i used them for the first time today and so far no free flow . but one octo is set lighter than the proton she dive thats rigged with it, this i do not like. i do not have guages but can tell a slight difference from the inhalation vacume thats required to get it to flow. i have a service manual from an older proton but not on the mr42. is the adjustment going to be the same on the 2nd stage? Also where might a person get a diagram of the rigging of a testing manifold system. Im a fireman and a scott scba tech. but im going to have to rig up something totally different for scuba. Thanks guys

 

[LeadTurn_SD]

When we talk about "cracking pressure", the units of measure are in inches of water. One way that works without instrumentation is to fill a deep pan or container with water, hook the regulator up to a tank, turn on the air, and then very slowy lower the 2nd stage you are testing into the water with the mouthpiece facing up.

As the regulator gets deeper in the water, the pressure (water pressure) on the 2nd stage diaphragm will begin to open the demand valve (by pressing on the demand lever). When air just starts to flow (a slight hiss), that is the "cracking pressure" in inches/H20. The distance measured is actually the distance the diaphragm is below the surface of the water when the air begins to flow.

You can carefully perform this test while holding a ruler next to the case of the 2nd stage, and measure how far below the surface the seam between purge cover and back of the case is when the demand valve "cracks" .

This method is actually described in the Mares repair manual, if you do not have a gauge. I'll need to check where exactly on the 2nd stage body you use as a reference on the Proton, but in the absence of advise from the manual, I'd just use the seam since it sould be "close" to where the diaphragm is.

Best wishes.

 

[maxmaxum]

Done and Done, thanks guys!

 

[LeadTurn_SD]

Hi maxmaxum,

Using the "water" method to measure cracking pressure should at least allow you to "match" the settings on your two Protons (set them so they both crack at the same depth).

Just a few more things (which you probably already know, but just in case):

1. Small adjustments of the 2nd stage orifice go a LONG way. I recommend 1/10 of a turn at a time (clockwise increases pressure on seating surface and increases cracking pressure, counterclockwise decreases).

2. Be sure to ALWAYS depress the purge button when adjusting the orifice to prevent "cutting" the soft seat.

3. Re-check and re-adjust lever height after adjusting the orifice. Again, a little goes a long way (a small turn on the nylock nut moves the lever quite a bit).

With the regulator pressurized and the lever height set correctly, there should be a slight "rattle" if you shake the 2nd stage (this is the demand lever tapping on the diaphragm), but no rattle when the reg is unpressurized. This rattle when pressurized indicates just a slight amount of slack between the lever and diaphragm.... if there is no slack, then the reg may be too sensitive and freeflow.... but too much slack, and it will breath poorly.... I raise the lever until the rattle just goes away, then slowly adjust it lower until it just returns.

Best wishes.

 

[Greg Barlow]

Excellent advice, thanks to u both. i used them for the first time today and so far no free flow . but one octo is set lighter than the proton she dive thats rigged with it, this i do not like. i do not have guages but can tell a slight difference from the inhalation vacume thats required to get it to flow. i have a service manual from an older proton but not on the mr42. is the adjustment going to be the same on the 2nd stage? Also where might a person get a diagram of the rigging of a testing manifold system. Im a fireman and a scott scba tech. but im going to have to rig up something totally different for scuba. Thanks guys

The adjustment will be the same with the Proton no matter what Mares diaprhagm first stage that you use. The only difference would be with the unbalanced piston R2 design, and that is contingent upon the cylinder pressure.

Lead Turn is correct in that you can use water to get a "ball park" figure for the cracking effort. Measure the distance from where the screw on front cover interfaces with the reg's body. A utility tub works pretty well for this test. Put a piece of masking tape on the side of the reg and make some marks at the 1.0, 1.25, and 1.5" measurements. It is actually pretty darn accurate if you have excellent hearing.

Another easy test is to lightly shake the second stage. If you can hear a light clicking sound while the reg is pressurized, it is in the ball park as well. You should not be able to hear any sound while depressurized. Try it a number of times to hear the difference.

Greg

 

[Greg Barlow]

Hi maxmaxum,

Using the "water" method to measure cracking pressure should at least allow you to "match" the settings on your two Protons (set them so they both crack at the same depth).

Just a few more things (which you probably already know, but just in case):

1. Small adjustments of the 2nd stage orifice go a LONG way. I recommend 1/10 of a turn at a time (clockwise increases pressure on seating surface and increases cracking pressure, counterclockwise decreases).

2. Be sure to ALWAYS depress the purge button when adjusting the orifice to prevent "cutting" the soft seat.

3. Re-check and re-adjust lever height after adjusting the orifice. Again, a little goes a long way (a small turn on the nylock nut moves the lever quite a bit).

With the regulator pressurized and the lever height set correctly, there should be a slight "rattle" if you shake the 2nd stage (this is the demand lever tapping on the diaphragm), but no rattle when the reg is unpressurized. This rattle when pressurized indicates just a slight amount of slack between the lever and diaphragm.... if there is no slack, then the reg may be too sensitive and freeflow.... but too much slack, and it will breath poorly.... I raise the lever until the rattle just goes away, then slowly adjust it lower until it just returns.

Best wishes.

Thanks...I should have read your explanation more carefully before submitting my own. Yours is better!

Greg

 

[maxmaxum]

They both worked great, lol. I got it where I need it. Thanks both for the info!