LDS BS in Nitrox class today...

[DevonDiver]

Really? I think thats Extremely debatable based on the Tons of posts that say otherwise... ie. that they didnt have problems UNTIL they serviced their reg.

Dont fix it if it aint broke... in the event of an acute, catastrophic 2nd stage failure to both my primary, secondary AND pony 2nd I'll surface breathing off the free-flowing reg.

Sounds like you know everything there is to know about the subject...so why ask the question?

All those hours on the internet paid off...and your foolish instructor was just wasting his time accumulating thousands of hours underwater......

 

[DevonDiver]

Of course it's false. A reg that breathes so badly as to not deliver enough air for recreational scuba diving is not "in need of service." It's in need of a trash can.

Utter nonsense.....

For decades pro divers did extreme dives on regs that by today's standards for performance, deliver very little air with high WOB. How did they ever manage? Why didn't they all pass out from CO2 retention?

More did...than do today.

Your pathetic arguement is akin to arguing against wearing seatbelts in cars or helmets on bikes.

And besides...some of the old regs performed just fine. Take the Poseidon Cyklon for instance....how many decades old is that?

It's ridiculous to assert that not having your reg serviced annually will cause this sort of thing.

CAN not WILL.

It's easy top justify cost-cutting when you haven't got enough experience to have encountered such problems for real.

I am not posting to support annual reg servicing...only to re-introduce a sense of perspective. Inexperienced divers read these forums...and IMHO nobody should be posting here with the attitude of "it's ok to save money at the expense of safety". You might think you understand the dangers...but that is very different to passing those beliefs on a global forum as if they were hard truths.

People don't hesitate to spend cash on shiney new kit and gadgets for diving... but then skimp on the costs of keeping their most important kit running smoothly. Idiotic.

 

[dave4868]

Kind of a detail, but elevated IP or IP creep on an older sherwood could only be caused by a poor seal at the HP seat, although I suppose if the cup washers were really worn out it could result in slight IP elevation. The piston head o-ring (the big one) separates IP from ambient pressure. If it starts to leak, IP drops, until the first stage opens, repressurizes the IP chamber, and it all repeats. The smaller piston shaft o-ring on this design also separates IP from ambient.

But, overall, I agree with your post that inlet filters rarely get clogged; it's almost always due to serious problems with either the tank or compressor used. I replace filters on my regs when I buy them (I always buy used regs) and inspect them periodically. Occasionally I've found crud in a filter after a charter dive with rental tanks. Not to point fingers, but there is a certain island in the northern caribbean with a central fill station (dive ops often do not own the tanks) that seems to be especially prone to lax tank maintenance. However, no matter how cruddy the filter has occasionally become, it has NEVER resulted in a noticeable increase in WOB in my case.

BTW, this is an excellent reason IMO to avoid the DVT gimmick on some regs. The filter is not visible on those regs and it is impossible to inspect it.

Good info, thanks!

Actually, IIRC, in my case, I found the big o-ring on the piston quite dry and thought it was sticking, not leaking. Couldn't the extra drag of a sticking o-ring cause the IP to creep up as the o-ring resists piston travel and hp seat closure?

I wish I could remember specifically, but it seems like I lubed the o-ring later and subsequently found the IP returned to normal (145psi). Might have just been a dream I had.....

The IP had gone up to 152, I believe, so maybe it was a simple matter of a poor seal at the HP seat, as you said. Funny that I seem to remember an improvement after lubing. Any sense in that possibility?

I'm sure I serviced the regulator shortly thereafter. I do remember that....

Dave C

 

[caseybird]

That should take you to the subject of how an IP gauge and a sink of water can be used to check your regs performance.
Enjoy

Please detail this process.

 

[redacted]

Please detail this process.

See if this helps: http://www.scubaboard.com/forums/regulators/260452-regulator-checklist-inspection.html If you still have questions, I'll be glad to try to help.

I forgot that the link does not really cover using a sink of water to check cracking pressure of your 2nd. Most 2nds have a cracking pressure spec on the order of 1.2 to 1.5 inches of water. Quality, high performance regs may be a ble to get the number below 1.0 (I have seen some that would get into the .6 to .8 range) but many have difficulty getting stable performance below 1.0 without freeflow problems.

Basically, you slowly lower your pressurized 2nd into a sink of water until it starts hissing. Most "standard" configuration 2nd are about 2.4 +/- .1 inches from the diaphragm to the opening of the mouthpiece. It is an easy way to get a fairly good estimate of cracking pressure without the professional gauges used by many shop techs.

 

[halocline]

Utter nonsense....Your pathetic arguement is akin to arguing against wearing seatbelts in cars or helmets on bikes.

And besides...some of the old regs performed just fine. Take the Poseidon Cyklon for instance....how many decades old is that?

My post was not nonsense, and has nothing to do with seatbelts or helmets, although I could have stated it better. Any regulator that is made by a major manufacturer and is in decent working condition will provide enough air for recreational diving. Servicing does NOT typically increase the flow rate of the reg, nor does it typically lower the WOB in any significant manner. There are occasional exceptions, but it's not typical.

The primary issue with this thread is that a dive professional tried to create a false link between spending money at the dive shop and safety. This is a common sales tactic; the fallacy is continually presented as something like "don't skimp, isn't your life worth X"

If regulators in recreational scuba were truly "life support" there would be many more dead divers, and people servicing them professionally would have to pass actual courses with exams and get actual licenses, with peer reviewed periodic testing, just like doctors and airline pilots. Instead the guy at the LDS "fixing" your regulator might have nothing more than a minimum wage job at the shop and a 1 day seminar in reg repair that nobody has ever failed. Maybe your shop has a great tech, maybe he/she is a hack. The point is, if people really died from this sort of thing, there would be SERIOUS liability, and resulting regulatory qualifications.

The whole point of diver training is that dive behavior, not equipment, is what determines safety. That's why we have the buddy system, recreational limits which allow immediate access to the surface, etc....

As a dive instructor, I would have thought you would understand this, but instead you seem intent on just criticizing my post and helping to perpetuate the dive industry's favorite myth, that we as divers can buy our way to increased safety.

 

[diverdavrecon]

It's life support equipment....get it regularly serviced.

 

[Mark_J]

I regularly service pretty much anything I own that has moving parts. I haven't once ever regretted doing so, in fact each time I usually see first hand the justification for regular scheduled maintenance.

While this thread was an interesting read, I do tend to agree with the Instructor of the Nitrox class in that a poorly operating reg could contribute to a higher level of CO2 retention. I still can't help but wonder why would anyone not want to have regular service on their regs?

 

[Meng_Tze]

....I do tend to agree with the Instructor of the Nitrox class in that a poorly operating reg could contribute to a higher level of CO2 retention. ....?

How would that work?

 

[redacted]

It's life support equipment....get it regularly serviced.

I agree. His livelihood and the livelihood of many other LDS key personnel may depend on it.