Piston or diaphragm 1st stage ?

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Centrals

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Nothing is perfect.
I dive exclusively sealed diaphragm but did use non sealed version as deco regs for a while.

How to look after the equipment properly is far more important than anything else. Tons of info available on the topic.
 

lowwall

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:cool:It’s like going into a firearms forum and asking 9mm vs 45? :cool:
More like a Browning Hi Power (piston) versus Glock 17 (diaphragm). The HP has all the romance and the potential for a better trigger pull, but it needs to be tuned and then cared for properly. The 17 is more utilitarian: cheaper and more tolerant of poor conditions and minimal care.
 

herman

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When I and my wife did buy our 4 regulators (in the seventies) there were not fully sealed first stages, either piston or diaphragms.
We did choose piston, the best available at the time: Scubapro MK5.
It was a good choice: those things are undestructible, we are still using them after 45 years...
The parts are all yet available and we managed to convert them to DIN and to make them oxygen compatible by mounting Viton O-rings and the MK10 conical seat.
However in 45 years the technology evolved and diaphragm regs improved their performances, to the point that nowadays they almost equalled a good piston, with significant advantages in terms of sealing.
Furthermore now a sealed diaphragm is significantly cheaper than an unsealed piston. Staying with Scubapro (the only brand which ensures 40 years of trouble-free operation and serviceability), a MK17 (sealed diaphragm) is just 188€, whilst a MK25 (unsealed piston) is 275€.
So I currently recommend the first one, either to a novice or to a skilled tech diver...

I agree with you on the MK-5/10s great regs but I will challenge you on the longevity of parts. USD/AL Conshelf (diaphragm reg) was introduced in 1965 (56 yrs) and rebuild parts are still available. To be honest, both of these regs are anomalies from an age aspect but it does show a well build reg will last a lifetime. And lets not forget the MK-2 (unbalanced piston), a great little reg that has well stood the test of time, still being made and parts are easily obtained. Considering it's low cost and widespread use in rental fleets, I would wager it has logged more dives than any other reg model.
 

Centrals

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Same as nearly all modern appliances nothing last for more than few yrs. It is a shame but....
 

Hoag

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More like a Browning Hi Power (piston) versus Glock 17 (diaphragm). The HP has all the romance and the potential for a better trigger pull, but it needs to be tuned and then called for properly. The 17 is more utilitarian: cheaper and more tolerant of poor conditions and minimal care.
So where would a CZ-75 SP-01 fit in?

Sorry. My bad. Back to our regularly scheduled programming. :rofl3:
 

tbone1004

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I'm a Fish!
It is obvious you don't like pistons since Atomic got bought by Huish. Regulators in general work, pistons or diaphragms. They work under water, salt or not. I also don't care if it's a "pain" for a tech to service my regulator. After all that's what the reg tech gets paid for. For the record, I also never screamed in pain when servicing my sealed pistons.

how is it you're correlating my dislike of piston regulators to Atomic being bought out by Huish? My dislike of Atomic is primarily rooted in them mismanaged by Huish, but my dislike of piston regulators is rooted in their inability to be sealed as effectively or efficiently as diaphragm regulators and has nothing to do with Atomic itself. Their fanboys however seem to think they are Gods gift to regulators which is irritating, but such is life.
 

Eric Sedletzky

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how is it you're correlating my dislike of piston regulators to Atomic being bought out by Huish? My dislike of Atomic is primarily rooted in them mismanaged by Huish, but my dislike of piston regulators is rooted in their inability to be sealed as effectively or efficiently as diaphragm regulators and has nothing to do with Atomic itself. Their fanboys however seem to think they are Gods gift to regulators which is irritating, but such is life.
There’s a lot of things that irritate certain groups that other groups do or talk about and vise versa, it’s part of the political climate of diving.
But sometimes we just need to step back and realize that we’re all in the sport because of one common thread, we all love to dive.
Dive and let dive.
 

Bigbella

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I have used both configurations and continue to do so, with little preference for one or the other; though, my unbalanced "compensated" regulators -- all decades old -- tend to be on stage or pony bottles, more often than not; but I do take all of my equipment out -- both diaphragm and piston -- on shakedown dives, after I service them.

Maintenance, I have to agree, is just about everything, regardless of design.

The only surprise that I am interested in, is decent visibility . . .
 
https://www.shearwater.com/products/peregrine/

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