1st Stage Reliability

[JahJahwarrior]

There are a few things that make this an interesting question, and difficult to answer with anecdotal evidence.

First is the fact that many regulators from different brands, have similar guts. Don?t ask me about what factories they come from, but one of the differences in reliability might be quality control, at the manufacturer or at the retailer, and especially in the soft parts.

Another is the fact that regulators are supposed to be serviced annually or so. I think a lot of cave divers don?t service their regulators annually, we use them until they break. A lot of us have the same $10 IP gauge and some orings and tools in our save a dive kits, and consider that we can just repair the regulator at the dive site. But most of us probably have a spare first stage, or an extra stage reg setup, so we can swap parts around if we have a boom at the dive site. I think knowing that regulators are reliable for longer might trick us into putting off service, and I?m guilty of this too.
It doesn?t help that most of us grow our regulator farms annually. It?s normal, you start with an open water regulator that might not be very tech looking, then get a doubles setup, then a deco set, then stage reg, then more stage regs, then a sidemount set, then rebreather, then your partner gets into diving and you do it all again. In the mean time, you find some black Friday deals, or some used regulators, and as you go, you shuffle regulators down the chain, keeping the newest ones on your backgas, and the stage regs and open water regs might be the worst, because you consider that if something happens to one of those, it?s not a big deal, just turn the dive, but you want good and recently serviced regulators on your backgas.

Then there?s how we use the regs. Every breathe is another impact of the HP seat but frequent diving for most of us is still just 2-4 dives per month. Salt is difficult to rinse out of unsealed regs, but sand is also a pain. I imagine that both are difficult on orings over time, but I haven?t had a regulator fail directly due to either of those.
One of the last things is that a right post regulator or single tank open water regulator can have a decent IP creep that isn?t noticeable as you are breathing it down. You turn it on for a check, then back off. When you go to dive, the freeflow you get you assume is from bumping the second stage, or hitting the water. For you, it?s still a reliable regulator, but it might really need servicing.

I don?t think there is any brand that is especially unreliable. I?ve gotten regs to last for 3-5 years between rebuilds. I?ve only had IP creep require a switch out on one dive and that was probably year 4 for that regulator, so no complaints from me. I?ve seen one turret regulator blow a diaphragm and I do believe there was a run of ?bad? seats. I keep a spare first stage in my toolbox, but I?ve only used it once. I?ve had many more issues with hoses, HP spools, and second stages seats, but I believe all except the Miflex hoses blowing up, were well past 1 year of use, so I can?t blame the regulators.

[mfascuba]

I've gotten years out of SP Mk20/25's between service visits. Run to fail. Dive Rite first stages for stages, O2 cylinders, deco bottles, etc. The stages and deco bottles invariably get shut down after initial splash in the water regardless of whether fresh or salt water, and then the purge button on the 2nd stage gets hit, it flushes water back into the first stage. Fresh water isn't so bad, but the salt will tear up the guts on those pretty fast. All part of the cost of doing business. Nothing like hearing salt water gurgling in the LP hose as you are doing deco in the ocean.

Also keep a few HP spools in your save a dive kit - might keep you from missing a dive from the tiny o-ring getting ground to paste.

[Kelly Jessop]

So the 'test' is proving that the Mk10 drains a tank faster in case of MP failure.. Not sure I see the correlation towards Performance here.

Far from a scientific test by any means,but in the case of the Mk10 v Mk20, it hints the Mk10 has better performance, in a beer and pretzel kind of test.

[Nitrogenius]

Far from a scientific test by any means,but in the case of the Mk10 v Mk20, it hints the Mk10 has better performance, in a beer and pretzel kind of test.

sure Kelly the 'unscientific' approach was well understood. I just have difficulties how a faster/stronger Flow from one first stage to the other should serve as performance indicator as only the Performance after the second stage seems relevant and whether the second stage performs better because of a higher Flow feil first stage is questionable at last.
BTW the test also to compare the first stages only would need to at least make sure they were operating at the exact same IP as otherwise the 'test' is flawed from the getgo..

[Kelly Jessop]

sure Kelly the 'unscientific' approach was well understood. I just have difficulties how a faster/stronger Flow from one first stage to the other should serve as performance indicator as only the Performance after the second stage seems relevant and whether the second stage performs better because of a higher Flow feil first stage is questionable at last.
BTW the test also to compare the first stages only would need to at least make sure they were operating at the exact same IP as otherwise the 'test' is flawed from the getgo..

I think the key is how much gas a stage can move, which may not translate to performance, but kicking in high flow etc, you want gas on demand. You are right a high flow 1st stage may do you no good if the second stage breathes poorly,but I have never felt constrained to matching brands. For example, my Sherwoods I use for sidemount have either Scubapro G250s or DiveRite unbalanced 2nd stage, because these second stages are reliable, but deliver a lot of gas. In this day in age when you can buy a stage versus a set, I never understood why people bought high performance 1st stages,but the matching 2nd stage was a dog.

[Nitrogenius]

In this day in age when you can buy a stage versus a set, I never understood why people bought high performance 1st stages,but the matching 2nd stage was a dog.

Agreed..

[gschaut]

I always loved my Sherwoods for first 30 years of diving. Totally bulletproof. But when I switched to side mount, the Sherwoods did not have the flexability (turret) for side mount hose configuration.

[Kelly Jessop]

I always loved my Sherwoods for first 30 years of diving. Totally bulletproof. But when I switched to side mount, the Sherwoods did not have the flexability (turret) for side mount hose configuration.

Strange, that is why I use them for sidemount because of the configuration worked well for hoses.

[mrki]

So assuming that they were operating at the same IP and the Mk10 actually has a higher maximum flow than Mk20. How does that that translate directly into better performance? Do we have any reports of people on Mk20s not getting enough gas? And not in a I'm-panicking-I-can't-breathe kind of way. Objectively not getting enough gas to satisfy their oxygen requirements? If hose failures happen 10 times more often than that, maybe it's Mk20 that has "better performance".