balanced diaphragm vs. balanced piston

[DivingDoc]

OK --

Which is better for recreational ocean diving -- balanced diaphragm or balanced piston? I've heard varying opinions from different LDS's.

One guy says that diaphragms are better because they are environmentally sealed and therefore don't corrode inside as much and that pistons rapidly decline in performance after their first use because of the fact that the ocean water gets in and corrodes the parts. (This guy sells and recommends the Mares Abyss as the best reg on the market)

The other guy says that pistons are better because if they fail, they free flow, but if the diaphragm fails, you don't get air, period. Also, they are easier to service because of fewer moving parts. (This guy sells and recommends ScubaPro as the best reg on the market).

So vote, and comment -- what say ye??

 

[Stone]

Oxyhacker's going to give you the best reply, so I'll just give an example in regards to the comments about balanced pistons:

All of my diving is ocean diving. I just overhauled my reg, my wife's reg, and one of my son's regs (Genesis balanced pistons, which are by no means top of the line). None of the regs (100+ dives each) showed obvious corrosion. I probably could have relubed the o-rings, flipped the HP seat, and been done.

As for a piston's performance degrading as soon as you use it, only one of the regs had an IP that crept slightly out of spec before it stabilized. Maybe the flowbench could detect a performance difference, but I couldn't.

 

[buff]

Piston vs. Diaphram is really not a concern for the recreatinal diver under "Normal" diving conditions. Both perform very well and with annual maintenance should last a lifetime.

 

[noshow]

Been told that getting one that is environmentally sealed id more important than piston vs. diaphram. Keeps the gunk and dirt particals out and id better for the first stage? ... or so I've heard.

 

[canuckton]

I agree, not an issue.

What is more interesting, when is piston superior and when is diaphragm superior?

 

[Tavi]

The results of the poll don't seem to match the responses posted.:mean:

 

[DivingDoc]

Exactly what I was thinking!

Support your votes, oh ye diaphragm choosers!

 

[noshow]

If I had to choose/vote then it would be/it was a diaphram.... :boom:

 

[DivingDoc]

Originally posted by noshow
If I had to choose/vote then it would be/it was a diaphram.... :boom:

What would be your reasons? For example, would it cause you to pick a Mares Abyss over a SbubaPro S600/MK25?
=-)

 

[noshow]

Good question, not sure, maybe. Any line's "top of the line reg" is a wicked reg. I think at that point it comes down to personal preference from what I can gather. If the MK25 is environmentally sealed then it's prob pick a hand. One LDS I've chatted with is totally sold on the fact that diaphragms are THE way to go, hands down. Another has said no big deal and suggested I pick a hand between the Apeks and Atomic. I have an Apeks so I guess I erred on the side of caution.

I would like to know the true facts....