Ok I bought this Mares 1st & 2nd stage:
Mares Prestige 12 Regulator
But also plan on buying & using this Metal Octo as my Primary because it is metal & I wont have cotton mouth:
Mares Proton Metal Octopus
I did this because I bought the 1st & 2nd stage combo when it was on sale for $150 shipped and always planned on using a Metal Octo for my primary 2nd stage & know Mares was one of the more "Affordable" metal regulators, so adding the $165 for the Octo & I have my entire life support for $320 which I feel is a really great deal on high quality equipment.
I know that Octo's are generally "tuned" differently than normal 2nd stages.
So how do I go about adjusting the Octo be be the Primary 2nd stage and then adjusting the current 2nd stage as an Octo? (LP said they wont calibrate the octo for me)
Sounds kind of quirky, but makes sense to me financially since I'm getting a metal primary for much cheaper than buying the metal 1st & 2nd stage combo.
Thanks.
I own and service several Mares regulators, among them Proton 2nds and MR-12 firsts. I will try to briefly describe what is involved in "tuning" your Proton and Prestige regs, but I'd highly advise taking "Option 1" (the short answer). It is not at all hard to do.... but you
absolutely need to understand what you are doing before tearing in to your 2nd stages.... and again, based on your question, I'd recommend the "Short Answer" below.
Short Answer: By taking your first stage and both 2nd stages to any decent reg tech. It should be a 5 minute job if they know what they are doing, and are somewhat familiar with Mares regs.
Long Answer: The Mares Proton Metal is a "classic downstream" regulator, unbalanced, with no external adjustment. To correctly tune your 2nd stages, you first need to test the intermediate pressure (IP) of your MR-12 first stage, then you can proceed to "tuning" the 2nd stages:
1.) Hook the regulator to a full tank, ideally with 2,500 - 3,200 psi.
2.) Using your IP gauge, make sure that your new MR-12's IP is within factory "spec".
3.) Measure the cracking effort of your Proton 2nd with your Magnehelic gauge. A well tuned and adjusted Proton, to be used as a Primary 2nd stage will "crack" at about 1.2" of water.... you can also use a basin filled with water and a ruler, measuring from the level of the 2nd stage diaphragm (about at the seam between front cover and body of 2nd stage) to the water surface to establish a rough cracking effort estimate.
4.) The Prestige 2nd may not need to be "de-tuned" for use as a 2nd, it just depends on how it came from the factory.... my experience is the factory "tune" is conservative with Mares regs. I set my Mares "backup" seconds to "crack" just slightly higher than my primary 2nds. About 1.5 - 1.6". You will need to handle them somewhat carefully at the surface to avoid accidental freeflow, but once submerged and full of water I've found them to be perfectly "stable" at this setting.
5.) To adjust the cracking effort on your Proton, you'll need to remove the hose (to access the adjustable orifice) and remove the side plug (to access the demand lever nut).
6.) A small turn of the orifice clockwise will increase cracking pressure, and turning counter-clockwise will decrease cracking pressure. A little goes a LONG way. Adjust and then test in 1/12 turn increments.
You must depress the demand lever whenever turning the orifice in order to prevent cutting and potentially ruining the 2nd stage soft seat! And you must re-adjust lever height each time you adjust the orifice.... turning the orifice clockwise will LOWER the lever, and counter-clockwise will raise the lever. So as you adjust the orifice, you are effecting the seating pressure on the demand valve, and the lever height, which effects responsiveness... it is a balancing act. Unless you have in inline adjusting tool, you will need to make a small adjustment, re-attach the hose and represurize the reg, test, and repeat until you have the correct adjutment.
7.) Lever height on the classic downstream (and all regs) has a big effect on how well the reg performs. Too low and it breathes badly, too high and it is too sensitive and freeflows easily. A properly adjusted Proton will make a soft "click" noise
when pressurized if you shake it... this is the lever striking the metal disk on the diaphragm, and indicates just a tiny bit of play (necessary to prevent the reg from being too sensitive).... the click will NOT occur when the reg is depressurized.
So.... if after reading the LONG answer your eyes have glazed over.... follow the advice in the SHORT answer. I strongly urge you to take the reg to a good tech, spend a few dollars, and have it done correctly.
Have fun with your new toy!
Best wishes.
