Why not a button gauge for stage bottles?

[dumpsterDiver]

I myself have always used PVC pipe extensions which go a little past the guage face to protect from scratches and also to absorb shock

 

[Jack Hammer]

I used to use the smaller button gauges and I could read them, but I found them a bit small to be very accurate. It was like reading a fuel gauge on a car, you know about how much gas you have but it aint spot on. Then I had an incident where I had to pass my stage to another diver and he couldn't read the gauge at all, which just added more stress to his situation. I changed them out and am happier with a larger easy to read gauge. YMMV

 

[DA Aquamaster]

On a stage bottle in a cave environment, you will often use a turn pressure of half plus 200 psi, or in some circles and/or situaions, 1/3rds. In either case, you need an accurate gauge that is easy to read. Even the new larger 1" diameter button gauges are still relatively hard to read with the degree of definition required as you have to interpolate between 500 psi increments. In terms of accuracy a quality brass and glass SPG will normally read within 50 psi of the actual pressure in the middle of the needle range. I contrast, a button gauge would be fortunate to be both accurate and readable to within 200 psi.

On the other hand, if you are just using the stage in OW water burning the stage before switching to back gas (with the total reserve in back gas) a button gauge may work for you. But there is a significant downside as it means the reg itself is now not as flexible in terms of the types of dives it is suited for.

 

[Trace Malinowski]

Hello Internets,

I have to rig a couple stages and I was thinking about using a button gauge instead of a short hose and brass/glass gauge...

I had a look around and everyone rigs stage bottles the same way, with the hose a gauge. Isnt this more failure points? Are button gauges crap (never had one)?

Thanks,
C

C -

Button gauges are very difficult to read as everyone mentioned. I had to make due with a button gauge while cave diving last month. They are better than nothing in a pinch. But, you'll want one that is very easy to read at all times in all lighting conditions.

If you had an SPG malfunction and a button gauge was all that was available as a replacement, it would get you through. If you were diving deco bottles and stage bottles and experienced an SPG malfunction and replaced it with a button gauge, you would be better placing the button gauge on a deco bottle. When diving stages, you'll want to be able to verify the pressure in the bottle accurately as DA Aquamaster pointed out. Deco bottles are more likely to be cached during a dive with all gas being usable - especially in smaller bottles.

So, if I were making a stage dive with an AL80 bottom stage, an AL80 deco bottle and an AL40, I'd stick the button gauge on the 40.

Button gauges are okay additions to the save-a-dive kits of tech divers. They are small, take up little room or weight when traveling, and can help other divers with pony, stage and deco bottles with immediate temporary fixes when it might be too time-consuming and unnecessary to correctly install an SPG, hose and cave line.

During a gas switch, a safe method of self-verification is to purge a reg with the deco bottle pressurized, but turned off, and watch the SPG needle drop. A button gauge makes such verification a bit more difficult and may slow the switching process for the diver or team.

 

[PfcAJ]

For me, its all about flexibility. I have a whole bucket of regs (its getting ridiculous, really), and I can grab any one of them and use it as a stage or deco reg. I've got good vision and I can read just about anything, but I want my equipment to be as versatile and standard as I can get it.

If something breaks on my backgas set, I can easily swap out the offending part with something from one of my extra regs and get back to diving! Of course, on dives where I need all the stage regs, I'm forced to tinker and make repairs, but quick replacements are certainly easier and quicker.

 

[DA Aquamaster]

For me, its all about flexibility. I have a whole bucket of regs (its getting ridiculous, really), and I can grab any one of them and use it as a stage or deco reg. I've got good vision and I can read just about anything, but I want my equipment to be as versatile and standard as I can get it.

If something breaks on my backgas set, I can easily swap out the offending part with something from one of my extra regs and get back to diving! Of course, on dives where I need all the stage regs, I'm forced to tinker and make repairs, but quick replacements are certainly easier and quicker.

It's good advice, and I do pretty much the same with the addition of ensuring all the first stages run at the same IP, making it very easy to swap any first or second stage during a trip.

 

[dumpsterDiver]

I have to admit, I use the button guage only on my oxygen bottle and on a back mounted pony. I think that in either of these applications, a plus or minus 250 psi is probably good enough. For a stage bottle that I was trying to calculate a turn pressure, etc. I think I would want a more legible And accurate guage myself.

 

[=C=]

I forgot that its all about the correct gear for the dive.

Soo... The stage is a deco bottle. We are diving 12L twins on air to 147FFW. The profile is almost straight down to the building, then up to the blastmans bunker and an old bldg on the stage EAN50. No overhead, just the odd ferry.

 

[Buoyant1]

I got one since it was cheaper at the time than getting the small brass & glass..I may eventually change, but as of right now it does what it needs to do...let's me know how much gas is in the cylinder, and I can read it while underwater.

 

[elan]

Hello Internets,

I have to rig a couple stages and I was thinking about using a button gauge instead of a short hose and brass/glass gauge...

I had a look around and everyone rigs stage bottles the same way, with the hose a gauge. Isnt this more failure points? Are button gauges crap (never had one)?

Thanks,
C

They do not give you required accuracy. The accuracy of the instrument can be determined by looking at the numbers standing by the notches. The accuracy is usually half a notch. So if you have them standing at 1000psi apart (that what I had on my old button gauge) then the accuracy is 500psi. Not good enough for a deco bottle. You might be reading 1000 psi while in fact the tank has 500 psi.