Regulator Question, is this normal?

[halocline]

The thing with this reg, if I read the first post right, is that both 2nd stages were leaking at some point, is that correct? That indicates an IP problem, so hopefully the tech at the shop made sure that the IP was stable and in the right range. I would go back to the shop and make sure this was done. It would not surprise me to learn that the IP was a bit high and/or creeping.

It is not uncommon for some new 2nd stages to leak a little as they break in, especially if A) they're unbalanced 2nds and B) the reg is new out of the box and have not been tuned or worked in a little by cycling the purge under pressure several times. In fact, someone, I think Peter Wolfinger's company, used to make a device to cycle 2nd stages, specifically for this reason. After I rebuild a 2nd stage, I usually leave it pressurized for several hours and tap the purge a hundred times or so over the course of that time. This also insures that the IP is rock solid.

 

[KD8NPB]

If it was tuned right from the beginning, it shouldn't really need that.

If it was tuned right from the beginning, it SHOULD need that.

I usually tune regulators within 1/8 to 1/16th of a turn from freeflow for maximum performance. Once the seat breaks in, it may develop a TINY freeflow.

This represents near perfect regulator tuning which is what all technicians should strive for.

 

[PfcAJ]

So perfect, that the customer has to take it back to the shop?

No.

This is a silly example of people trying to get too slick with their gear and causing problems. ESPECIALLY for a new diver who doesn't know better. Their freshly serviced/ brand new reg is now 'leaking' when their on a trip to Bonaire. Great. Exactly what they wanted.

Maximum performance... baloney. Most divers can't even tell, and the ones that can tell can probably adjust it themselves, anyways. I own a BUNCH of regs, and the last thing I want to do is fiddle with them at the dive site because some tech tried to get cute.

 

[KD8NPB]

So perfect, that the customer has to take it back to the shop?

No.

Excessive seat-to-orifice contact may cause premature failure of the seat.

Plus, when I used to have my regs serviced, I expected maximum performance. The air gets a tad dense past 100 ft...

 

[halocline]

Well, that's why you should pressurize and cycle the reg many times before giving it back to the customer. That way you can tune it for best performance and it won't start leaking after a dive or two.

In general though, I tend to agree that most divers are not going to perceive 1/4" of water difference in cracking effort. I've had some interesting experiences sharing air with divers that have expensive regs that don't perform that well because (presumably) they're out of tune; they have no idea. Ignorance is bliss! And it really doesn't matter, a dive breathing off a reg that cracks at 1" is just as enjoyable and safe as one that cracks at .75", unless you're an obsessed knucklehead, but we don't know anyone like that, do we.....

This is one nice thing about balanced 2nds; they're easier IMO to tune and hold a tune, because there's so much less spring pressure on the seat when not pressurized. The balance chamber provides the pressure in proportion to IP.

---------- Post added December 11th, 2012 at 08:59 AM ----------

Excessive seat-to-orifice contact may cause premature failure of the seat.

Plus, when I used to have my regs serviced, I expected maximum performance. The air gets a tad dense past 100 ft...

This is a good one. If the orifice on a 2nd stage was grinding into the seat hard enough for the seat to fail, you'd have to have suction like a high price 'escort' just to get a breath.

And if you're having performance problems at 100 ft, it's got nothing to do with your 2nd stage. That's a first stage problem; the 2nd stage flows the same volume of air at all depths. Extra density wouldn't slow it down until it got 'thick' enough to have a real-world increase on friction, and that's a LOT deeper than anything recreational.

But, I agree that in general it's nice to have your regs performing at their best, and I agree that tuning an unbalanced 2nd stage extremely tight will wear the seat more in storage than tuning it for best performance. But failure? No way, and anyhow the difference in breathing would be so extreme that most divers wouldn't accept it.

 

[PfcAJ]

Excessive seat-to-orifice contact may cause premature failure of the seat.

Plus, when I used to have my regs serviced, I expected maximum performance. The air gets a tad dense past 100 ft...

I wouldn't know. I don't dive anything but trimix past 100'.

 

[Scott L]

If it was tuned right from the beginning, it SHOULD need that.

I usually tune regulators within 1/8 to 1/16th of a turn from freeflow for maximum performance. Once the seat breaks in, it may develop a TINY freeflow.

This represents near perfect regulator tuning which is what all technicians should strive for.

The likelihood of a regulator malfunction is at it's highest immediately after servicing.

 

[cerich]

Some techs tune a reg so it is on the very edge (pun intended) of a freeflow for max. performance, some will back it off so it won't start to freeflow after the first few dives. There isn't so much a "right" or "wrong" to either way as long as the owner of the reg is aware of which one has been done (accepts it will need tuning after a couple dives or accepts less than absolute max ease of breathing from the reg).

We recommend the selling shop present that option to the buyer of the reg and tune according to the owners wish.

This is not uncommon with any brand of regulator.In fact there is a bench fixture that will actually help techs break in the knife edge oriface and seat (both first and second stages)http://www.scubatools.com/p-599-quick-set-poppet-seat-break-in-fixture.aspx that we recommend shops purchase and use in servicing and pre delivery tune (sorta like a car dealership does prep as well), it really reduces issues like yours. Every brand I am aware of recommends the dealer do a pre delivery tune. (I have doen the tech class for Scubapro, Mares, Dacor, Sherwood, Genesis, Oceanic, Aeris, Poseidon,Sea Quest, Aqualung, Draegar and a couple others I am sure I missed... ) I have taught the repair class to dive shops for Mares, Dacor, Oceanic, Aeris and currently for EDGE and HOG of course.


We also recommend that any diver take a quality Equipment specialty course that will teach users the reasons and fixes for easy stuff like this. If that gets you interested step up to a TDI/HOG repair Specialty Class from a HOG Dealer that will get you well into the details of it all.

 

[oldschoolto]

I like to make the octo reg crack at 1" to 1 1/4" or so... I "HATE" a regulator that's constantly free flowing, For most divers it's just not needed to crack at 1/4 inch... I don't have any fancy tools... Just use the kitchen sink and a IP gauge ... Works just fine... I set the crack on the 2nd stage regulator about 1/2" to 3/4" and they breath easy... I never do any diving that would call for max performance in a regulator...

Jim...

 

[KD8NPB]

This is a good one. If the orifice on a 2nd stage was grinding into the seat hard enough for the seat to fail, you'd have to have suction like a high price 'escort' just to get a breath.

Debatable. A few grams of pressure is all it takes to cut a ring in the seat over a short period of time. That doesn't translate into much seat height.

And if you're having performance problems at 100 ft, it's got nothing to do with your 2nd stage. That's a first stage problem; the 2nd stage flows the same volume of air at all depths. Extra density wouldn't slow it down until it got 'thick' enough to have a real-world increase on friction, and that's a LOT deeper than anything recreational.

If I'm already breathing mud, the last thing I want to do is have to fight 1.0 in-h2o versus my personal regs which I keep set at below 0.5 in-h2o.