Mixing Atomic First and Second Stages (Plus advice grovel in thread)

[Jackie Treehorn]

First post on SB. Been lurking a while. Here is my situation:

I'm a new diver (1 year diving, 150 logged dives, PADI MSD). All my diving is in warm water reef/wreck settings.

I have an ST1 with an SS1 Titanium. I replaced a Ti2 Octo after my first 5 or so dives for the SS1 as I wanted the safe second configuration.

I'm considering using my Ti2 as a second stage for a pony setup (13cf or 19cf). To give me the most flexibility, I was considering a M1 DIN as the first stage with it. The idea being that I would have a DIN unit handy if I needed it, and a first stage geared for more techie stuff I i decide down the road to do that.

My other thought was to just get a DIN first stage of the ST1 as that guy has been awesome so far!

Thoughts? Advice? Flames? All would be appreciated!

 

[guruboy]

It doesn't matter what atomic you use. They all perform the Same.

 

[Jackie Treehorn]

Yeah, that part I figured out from searching around. But what about the ST1 vs the M1 as first stages for the pony?

Just looking for opinions and thinking it all thru before pulling the trigger.

 

[diversteve]

I wouldn't use an Atomic 2nd stage for a pony if you're going to dive it with the valve shut-off as the Seat Saver Orifice on all of them will allow water to seep into the hose/first stage while it's wet. I believe the Ti2 has an SSO also but I'm not positive on that older model.

I don't see any advantage of the ST1 over the M1? Monel is inert so depending on what's in the pony it might be better. Actually the difference in the stages is pretty much the material used so you could save money by going with a Z2 - they all breathe the same.

My choice for a pony (I don't have one) would be the Zeagle Envoy RaZor since it incorporates the valve into the first stage. Envoy RaZor Of course it doesn't function as a backup DIN reg.

 

[Jackie Treehorn]

Hmmm... you've given me something to think about there. My thought was to dive with it charged but valve shut off. Getting water in my first stage of something I wouldn't reguarly be using sounds like a receipe for disaster.

Thoughts on the ST1 vs the M1 was corrosion resistance vs. gas flexibility if I later wanted to get into tech diving.

The razor pony system looks cool and I had already considered it. I'd lose the ability of a DIN setup and I've only dived with Atomic so there is a trusted level of comfort with using what is familiar.

I'd love more thoughts if they exist. Thanks!

 

[guruboy]

For a pony you can just leave it on the entire time.

 

[Scared Silly]

I wouldn't use an Atomic 2nd stage for a pony if you're going to dive it with the valve shut-off as the Seat Saver Orifice on all of them will allow water to seep into the hose/first stage while it's wet. I believe the Ti2 has an SSO also but I'm not positive on that older model.

The above is more or less correct. But when using a pony bottle or really any bottle pony, travel, deco, etc that will not be used immediately what one should do turn it on to pressurize both the first and second stage. Whether one decides to turn it off or leave it on is a personal decision.

For instance, IMHO for a pony bottle that is tank mounted it should be left on. Simply because reaching back and turing it on when Davey Jones is calling is one task that one should not need to perform. If the bottle is slung like a deco bottle then turning it off is reasonable as one can easily turn it on. Once off then there is the chance during the dive that the regulator will depressurize. Which then as noted above may lead to water seepage.

II don't see any advantage of the ST1 over the M1? Monel is inert so depending on what's in the pony it might be better. Actually the difference in the stages is pretty much the material used so you could save money by going with a Z2 - they all breathe the same.

My choice for a pony (I don't have one) would be the Zeagle Envoy RaZor since it incorporates the valve into the first stage. Envoy RaZor Of course it doesn't function as a backup DIN reg.

For a pony/backup reg I would just find any Atomic first stage on the secondary market and use it.

 

[BoltSnap]

A pony bottle regulator should always be on ready for the unlikely chance the diver or his buddy are OOA. In this case, you don't have the time to putz around to remember that the pony is off and for you to turn the air on for ANY regulator. With Atomic regulators (or any high performance regulator with venturi and/or cracking pressure adjustment), the adjustment knob for the cracking pressure should be turned in for the highest effort when the second stage isn't in use.

The M1 gives you the option to use higher O2% than 40% should you decide to use with as a deco bottle if you go tech. Whatever you decide on, ST1, M1, etc., you should use a regulator with a swivel turret on the first stage to make it easy when using the second stage should you need to use the pony. I don't see the point to use the much more expensive ST1 on a pony over the M1 or the sealed B2 (M1 is best IMO).

 

[Jackie Treehorn]

Thanks for the replies. The M1 it is.