Guide to Mares regulators from 2000-2020

[lowwall]

I have an orphaned MR42T - so no hope for me to get the latest environmental sealing kit or orher improvements? Else, it’s been a solid reg in the time I’ve became a diver.

Nope. But at least you can still get parts. Service kits, the poppet and the seat are all available on multiple sites. The diaphragm is the same one as the 15X.

There was an environmental seal kit for it, called the Cold Water Dry kit. It's not stocked anymore, but they will occasionally come up if you really want one. The part number is 416852. I don't see any advantage outside of freezing water. It's a diaphragm reg with a big hole into the ambient chamber, so the guts are sealed away and the ambient chamber is easy to rinse.

 

[Nedster]

Thank you for this. It is super informative.

 

[Valtman]

I kind of doubt anyone planning a normoxic Heliox dive to 200m (656') is going to consider a budget regulator like a Mares 15X.

I kinda doubt anyone is planning a normoxic dive past 60 meters at all. I hope not.

To the point...

Last year after a bit of research I ended up buying a second hand Abyss 22 single tank reg. It was the old version, came with a no name secondary, rubber hoses, kinda ugly so I sold (no gifts, I'm poor) that to my girlfriend and found a really fresh 22X version for myself. I truly love it's performance - at least in shallow warm water. My Apeks's feel like rubbish now.

Today I acquired a couple of MR12ST's, two more Abysses and two Prestiges. Oh, and a three button Suunto Zoop into the bargain. Spent a total of 320 €. My plan is to build an Abyss 12S sidemount set using swivel adapters on the 1st stages. If for some reason it doesn't work out they'll be my stage regs. If it does work out maybe I'll get couple more 12's to be the stage regs with the Prestiges.

Should there be any problems getting the 12's O2 cleaned BTW?

I'm looking to get CWD Dry kits for the regs. Some websites say the same kit goes for 12S and 22. The most reasonably priced kit says it's only for 12S. Not all MR12ST's look the same. The one (propably the most current, 2011?) on the product picture for the CWD Dry kit seems to have the main barrel in two pieces where as mine are all solid from the DIN wheel to the plastic end cover. Thinking about the backwards compatibility/upgradability of Mares regs all the same parts should fit in all of the regs that have the same number, right? If not between different numbers as well.

I also started thinking if I need the CWD kits at all. They do perform quite well without them? Where would you draw a line for needing the kits? I'm in Finland so the water will be more or less 4 degrees year round. Most of my diving will be elsewhere though. Does depth play a role in the equation? I do want a setup that will eventually take me safely and reliably to at least 100 meters.

Or is my plan doomed from the start, should I buy more Apeks's instead?

I love this thread, learned so much, thanks!


Cheers
Valtteri

 

[lowwall]

I kinda doubt anyone is planning a normoxic dive past 60 meters at all. I hope not.

Argh. Hypoxic, not normoxic. Why didn't anyone notice within the edit window?

I'll need some more time to answer your questions about cold-water kit part numbers. Except to say that most of the folks who used to dive these regs in water temps like yours didn't bother using them.

But they weren't regularly taking them to 100m either. Maybe pick up some of the older, heavy MR22 firsts for that and keep the 12 for stages? Or, since it's sidemount, I guess you can experiment with one of each. I'm excited to hear how it works out.

 

[Valtman]

Argh. Hypoxic, not normoxic. Why didn't anyone notice within the edit window?

I'll need some more time to answer your questions about cold-water kit part numbers. Except to say that most of the folks who used to dive these regs in water temps like yours didn't bother using them.

But they weren't regularly taking them to 100m either. Maybe pick up some of the older, heavy MR22 firsts for that and keep the 12 for stages? Or, since it's sidemount, I guess you can experiment with one of each. I'm excited to hear how it works out.

I specifically wanted the 12's for their light weight, small size and (with the swivels) optimal hose routing. The 22 actually would work quite nicely when mounted "upside down" and using only button SPGs. I'd still go with the 22X since I think my DSTs are already excessively heavy. Having 3 - 4 of those, or just two old 22's in front of you really f's up your trim. Using two different regs with a half a kilo weight difference means you're diving sideways, not worth experimenting.

If there was an option I would have considered something that's still produced, but this form factor seems to be only used by piston regs nowadays. Maybe 2S would work just as good, but they can't be environmentally sealed which made me choose to stick with diaphragm regs. The flagship Scubapro is a piston reg though...

It will take time before I'm anywhere near 100 m, but I'll get there eventually. Still waiting for that magical 10k to appear on my bank account for the CCR. So they would be bail out regs anywhere past ~50 m, but even more so they need to be reliable. I think I'll start without the CWD kits, see if I feel the need for them when things get more serious.

With two regs if icing would happen you just let that reg warm up while breathing on the other. And why do we practice feather breathing if we never get to do it for real? Tech divers plan for failures but of course we also consider every piece of equipment to minimize the chance of a failure. The swivels surely make the setup more fragile but other than that I don't think there's still anything better on the market than an old Mares. I'm sure someone will get mad when I show up for big boy dives with my unsealed "vintage" regs.

Is there any real world benefit for DFC? The right side/long hose would use that port, not the left/short hose, unless I do some really weird hose routings. Will I notice a big difference between the regs?

I'll post some pictures when I have the rest of the parts and get to build this puzzle.

 

[lowwall]

Ok. I see where you are going. A DIN 12 is a really compact first stage.

You definitely do not want a 2. It's an unbalanced piston so freezing is a legitimate concern at 4°C. Also the WOB increases as tank pressure decreases. It's not a big difference, but I'm sure it would be very noticeable with the higher density gas at your depths.

 

[lowwall]

Today I acquired a couple of MR12ST's, two more Abysses and two Prestiges. Oh, and a three button Suunto Zoop into the bargain. Spent a total of 320 €. My plan is to build an Abyss 12S sidemount set using swivel adapters on the 1st stages. If for some reason it doesn't work out they'll be my stage regs. If it does work out maybe I'll get couple more 12's to be the stage regs with the Prestiges.

Should there be any problems getting the 12's O2 cleaned BTW?

I'm looking to get CWD Dry kits for the regs. Some websites say the same kit goes for 12S and 22. The most reasonably priced kit says it's only for 12S. Not all MR12ST's look the same. The one (propably the most current, 2011?) on the product picture for the CWD Dry kit seems to have the main barrel in two pieces where as mine are all solid from the DIN wheel to the plastic end cover. Thinking about the backwards compatibility/upgradability of Mares regs all the same parts should fit in all of the regs that have the same number, right? If not between different numbers as well.

OK, there are 4 basic versions of the "modern" (post-Voit) 12. They came in yoke and DIN. There were also EN 13949 Nitrox versions with its different threads for Europe (well, France) and a parts kit to convert to that version. Those got NX added to the reg name.

These are in chronological order from left to right. The oldest one has 1HP port and a fixed orifice. You don't want that one. Then came the MR12T, which in turn was followed in 2008 by the original MR12S, normally just called 12S. Mares updated the 12S in 2011. They left the labeling on the reg the same, but internally call it the "12S 2011" or "12S 2k11". The ring on the metal body makes it easy to spot the original 2008-2010 12S.

The changes were minor, but the the MR12T and 12S originally required different service kits. A couple of years ago Mares decided to consolidate their MR12 service kits by including the parts, including the HP seat/poppet, for all variants into one kit (and charging more for it). This is 46201370 for the the kit with rubber O-rings.

If you want to go over 40% O2, you'll need to get them O2 cleaned - which should not be a problem - and then find a service kit that uses Viton O-rings. The universal Viton kit is part # 46201371. I don't think they are still making it, but they do come up for sale occasionally. The original MR12T Viton service kit is # 46186154 which is discontinued, but you can use the NX version which is part number 46200678. The original part number for the 12S DIN Viton kit is 46200966 which is very hard to find.

I don't know if the NX service kit has everything you need for the 12S. Does anyone? It should be close and you can definitely buy any missing o-rings individually from scubagaskets or similar.

The next question was about the CWD kits (aka coldwater kit aka environmental seal kit). This is more straightforward. The MR12T and the 12S 2k11 uses the same kits as the 22: the dry kit is part number 416855 and the oil-filled kit is 416851. The 12S from 2008-2010 had its own dry kit with part number 416856. The only one of these still in production is the oil kit because it's used on the (Abyss) Navy 2. But there's still a few new old stock of the others floating around if you decide you need them.

 

[Valtman]

Thanks!

So mine must be the 2011 version but they are the size of the 2008 version in your picture. What's up with that?

The "reasonably priced" CWD kit is the 416856... I could get the 416855 kits now for ~130 €. (2x + shipping from Switzerland.) I guess they are not going to get any cheaper in the future.

I should also get a couple of 46201370 service kits and... Six, we have six Abyss 2nds in the family, so six 46186160 service kits. Plus two 46201355's for the 22's we have. The same kit goes for the 22X and the old chonker? I should also learn to service my own gear.

www.maremossoforzasette.it seems to be a good source here in Europe for service kits, shipping is 5,90 €.

For O2 clean stuff I think it's easier and cheaper in the long run to go for the 2S. Brand new 1st stage costs about the same as getting an old one cleaned and serviced. They'd have a MOD of 21 meters and at least Mares says they've been tested in extreme conditions so they should have adequate performance. What do you think?

Again thinking well ahead in the future, is it possible to convert a Mares 1st stage to have fixed IP? These are used in mCCRs for the O2 when using a mass flow orifice, or a "leaky valve". Rising IP with increased depth would introduce too much O2 in the loop. I think this is usually done by replacing the flexible part of the environmental seal with a rigid one.

 

[Jens Bölte]

Hello

2x + shipping from Switzerland.) I guess they are not going to get any cheaper in the future.

Buying products from Switzerland will always be expensive. Mares does not normally sell service kits and spare parts to end users. Is there no dive shop in your area that would order the CWD for you?

I think this is usually done by replacing the flexible part of the environmental seal with a rigid one

Yes, reVo, who now use Mares regulators, use a metal plate instead of the flexible diaphragm. I have never seen the rigid metal plate in the catalogue, but maybe reVo sells them.

Best wishes Jens

 

[lowwall]

So mine must be the 2011 version but they are the size of the 2008 version in your picture. What's up with that?

They are the same size. It's just a photo artifact.

The "reasonably priced" CWD kit is the 416856... I could get the 416855 kits now for ~130 €. (2x + shipping from Switzerland.) I guess they are not going to get any cheaper in the future.

Ouch. Might not be worth it. Most people who used these when they were new didn't bother, even in your temps.

I should also get a couple of 46201370 service kits and... Six, we have six Abyss 2nds in the family, so six 46186160 service kits. Plus two 46201355's for the 22's we have. The same kit goes for the 22X and the old chonker? I should also learn to service my own gear.

www.maremossoforzasette.it seems to be a good source here in Europe for service kits, shipping is 5,90 €.

That's where I bought most of my kits and also my 22.

No problems. Except I sometimes got different versions of what they had listed. For the kits it was good because they sent the latest version. For my 22, it was annoying because it was supposed to be a 22X which was never sold in the US, but when it showed up it was an MR22T. I kept it because they didn't actually have a 22X to exchange for it and the price was really good.

For O2 clean stuff I think it's easier and cheaper in the long run to go for the 2S. Brand new 1st stage costs about the same as getting an old one cleaned and serviced. They'd have a MOD of 21 meters and at least Mares says they've been tested in extreme conditions so they should have adequate performance. What do you think?

I think I'm getting out of my depths here. Let's start with the easy question. The R2/2S should be fine. The only concerns with unbalanced piston regs are low tank pressure performance and increased susceptibility to freezing. But these issues go away for deco tanks as you'll never be pushing large volumes of gas through them.

But I can't answer whether you can use a new reg for rich mixes. First, I'm not even sure what you will be using. A MOD of 21m is a weird number, that's 51.6% at 1.6 ppO2.

Anyway, there's no way to know if Mares non NX regs are assembled with 100% O2 safe lubricants. I'd guess they are, but Mares only states they are safe to 40% so the CYA answer is that even new regs should be O2 cleaned and serviced before use. And what are the local thoughts about using standard nitrile rubber o-rings with mixes over 40%? FWIW, DGX says it's OK: Is it safe to use rubber O-rings with Nitrox? | Dive Gear Express®

Again thinking well ahead in the future, is it possible to convert a Mares 1st stage to have fixed IP? These are used in mCCRs for the O2 when using a mass flow orifice, or a "leaky valve". Rising IP with increased depth would introduce too much O2 in the loop. I think this is usually done by replacing the flexible part of the environmental seal with a rigid one.

Now we are definitely beyond the limits of my knowledge. I have no idea. How does this even work at the depths you are talking about? Ambient pressure at 100m is equal to the surface IP for Mares regs.