The "right" octo to pair with Atomic ST1?

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BoatingDave

Contributor
Messages
124
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Location
Philadelphia, Pennsylvania
# of dives
50 - 99
So I am leaning on getting the Atomic ST1 reg, I like the stainless steel strength and corrosion resistance, environmental sealing, and think that titanium (Ti3) would be overkill for me.

I may be doing some cold water diving (no ice diving) but may be in water around 50 F, so I like that freeze protection comes standard. However, there is no Atomic ST1 octo so was leaning towards the M1 octo to pair with it. It also has standard freeze protection.

So my questions:

1. Is this a reasonable pairing? I am willing to pay a bit more for a quality regulator given the importance of the reg... Or should i not worry about freeze protection on the second stage and go with the Z3?

2. if "freeze protection" really a first stage issue, and I would be fine with a cheaper octo that is unlikely to freeze if needed for a few minutes at depth when making an ascent with a buddy (or me) in trouble.

just not 100% sure where my focus should be. I am a fairly risk averse person so want to make sure I am doing things safely.

Thanks
 
I have two ST1 second stages in my ST1 regulator setup. I have the primary on a longer hose, 40", since I donate the primary. The second ST1 second stage is on a 24" hose and that's the one I'll use when I donate my primary ST1 second stage to my buddy. In other words, I have two ST1 second stages or matching second stages.

The main and only issue with the set up I have is that the ST1 second stage comes with a VERY expensive hose with permanently attached swivel. This hose setup makes the ST1 second stage unnecessarily very expensive.

The second best is to use an M1 octo but it won't be much less expensive I think. The third option is buy a Z2 octo and all is well.

50F water isn't very cold and doesn't require more cold protection than what is already available on any of Atomic regulators.
 
Get the cheapest one you can, they all breath the same. The M1 and Z2-3 all have zirconium plated air barrel, the only difference is the exhaust deflector and diaphragm cover. T and B Regs have titanium air barrels, I think the ST1 has stainless. I’ve bought two T series an older T1 and converted it to J seat T2x with Monel piston and swivel retainer, and a T2x, buying used you can get them for less than a new ST1.
 
@BoatingDave SS has no strength benefits in this application FWIW. The brass is more than strong enough, and for corrosion resistance, the chrome is certainly more than good enough. Not bashing the regs, but it's not something I'd pay more for.

That said, if you want the ST1, just get another ST1 second stage to match. There is nothing special about the "octo" version of any reg other than some color changes on some of them. Just dive matching ones like @BurhanMuntasser said. Echoing what he said, their proprietary hoses are stupid and to add insult to injury, if you want to replace it with a normal hose you have to pony up another $25 or something for the collar so the standard hoses seal. If you get an Atomic with the swivel hose, PLEASE get that collar when you purchase the reg and keep it in your save a dive kit/regulator bag. In the event a hose blows out or something else where you want to change the hose, you will up the proverbial sh!t creek without a paddle if you don't have it.
 
Like Burhan's suggestion of an M1 Octo. They're $350, the ST1 octo is $429 for the same performance in stainless. Monel is inert - does not corrode.

Z2 octo's are $289 so for $60 I'd get the M1.

The reason to buy Atomic - besides their excellent performance - is so your dealer can service both stages.
 
I always forget about the “comfort swivel” because I take them off before I use the regulator, the “jam nut” costs $12, a nice hose of a more sensible length (like a 22/24” for over the shoulder or 40/44” for under the arm, $25ish and you can sell that brand new Atomic hose for $75 to $100.
 
There are only two differences in the Atomic second stages. M1/Zx have a zirconium inlet tube whereas the others are titanium. The M1 has a stainless steel orifice whereas the others have a titanium orifice. Everything else is cosmetic and bling. Zirconium has better heat conduction properties than titanium. Me, I would just get a Z2/Z3 second stage and go dive.
 
https://www.shearwater.com/products/teric/

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