Deco bottle SPG

[MaxBottomtime]

I agree with Rick on this one. I am a relatively recent button gauge convert. They are low profile, less prone to snagging, are virtually indestructable and they also eliminate two o-rings in the HP spool and a potentially leaky HP hose.

And they are inexpensive at $25-$35 each - about 1/3 the cost of a good brass SPG.

They are not quite as easy to read under water, but then you don't need to read them that often and when think you may need to, you are hanging on a deco line with nothing better to do anyway. They are really of more value on the surface to double check the pressure before the dive as you either are going to plan properly and have enough or you won't. If you screw it up and run short, having a gauge tell you you're screwed won't make it any better.

I had this same argument on another list. It makes more sense to me to use a pressure checker at the surface. Since after opening the valve to pressurize the hose, then shutting it down to protect against leaks until you actually switch to your deco bottle there really is no need for an spg at all. As you said, if there's not enough gas to complete your deco, having an spg won't give you more.

 

[matt_unique]

I had this same argument on another list. It makes more sense to me to use a pressure checker at the surface. Since after opening the valve to pressurize the hose, then shutting it down to protect against leaks until you actually switch to your deco bottle there really is no need for an spg at all. As you said, if there's not enough gas to complete your deco, having an spg won't give you more.

If for whatever reason you do run short on deco it would be better to know in advance than to begin to notice great breathing resistance then your last breath from the tank. This is not a conversation about what to do to ensure this never happens of course but if you ended up at this point. I would personally prefer to know by looking at my gauge to decide how much time I should spend returning to my backgas for decompression.

--Matt

 

[DA Aquamaster]

If for whatever reason you do run short on deco it would be better to know in advance than to begin to notice great breathing resistance then your last breath from the tank. This is not a conversation about of course but if you ended up at this point. I would personally prefer to know by looking at my gauge to decide how much time I should spend returning to my backgas for decompression.

--Matt

If you planned the dive properly, dove the plan and brought along an adequate deco gas supply and reserve (1.2 works, 1.5 is better), it won't be an issue. Losing access to the deco gas entirely is another matter entirely and you should have a separarate contigency plan already developed but again, an spg would make no difference in that situation either.

So while it is not a "what to do to ensure this never happens" conversation the two are pretty closely linked - if you plan and execute the dive properly, you really don't need an SPG on the deco bottle during the dive, and if you don't plan and execute your dives properly, an SPG on the deco tank is going to do very little to extend your diving career anyway.

Again, I used to be a believer in a large SPG, but I just don't see the benfit of having one along anymore. A button gauge SPG makes a nice compromise. It almost unnoticeable when it's along on the dive and if you absolutely need to reassure yourself during the dive that there is still adequate gas in the deco bottle, it is accurate enough to suffice for that purpose.

 

[matt_unique]

If you planned the dive properly, dove the plan and brought along an adequate deco gas supply and reserve (1.2 works, 1.5 is better), it won't be an issue. Losing access to the deco gas entirely is another matter entirely and you should have a separarate contigency plan already developed but again, an spg would make no difference in that situation either.

So while it is not a "what to do to ensure this never happens" conversation the two are pretty closely linked - if you plan and execute the dive properly, you really don't need an SPG on the deco bottle during the dive, and if you don't plan and execute your dives properly, an SPG on the deco tank is going to do very little to extend your diving career anyway.

Again, I used to be a believer in a large SPG, but I just don't see the benfit of having one along anymore. A button gauge SPG makes a nice compromise. It almost unnoticeable when it's along on the dive and if you absolutely need to reassure yourself during the dive that there is still adequate gas in the deco bottle, it is accurate enough to suffice for that purpose.

Ha ha - this reminds me of the scene from Captain Ron when they run out of gas in a storm enroute to an island. Ron says "I know we must be close because we only had enough gas to make it...and we just ran out of gas!"

The same could be said for having an SPG anywhere including your back gas. I agree the SPG will not change your situation if you planned incorrectly but as a matter of principle I would not dive without an SPG on my gas supply. You can't plan for every possible contingency.

--Matt

 

[teckhead]

Hi Jason, i use a brass spg also for my deco tanks, so if you can aford it , go for it , since your be diving for a long time best to have the best, (i imagine)
and yes Jason , if you use richer than 40% it need,s to be 02 clean.
just my 2 cent worth!

 

[wedivebc]

, if you use richer than 40% it need,s to be 02 clean.
just my 2 cent worth!

Where can I get my gauge O2 cleaned? I asked at the dive shop but the idiot there looked at me like I was nuts...

 

[Tamas]

Hay Jason I know exactly what you mean. I had a couple of US Divers Micra regs laying around and wanted to use them for my deco regs. I had one hell of a time getting people to except the fact that they would work just fine. People kept telling me that I didn't need a balanced first stage for a deco reg and that I should just buy another cheap unbalanced reg instead. I kept telling them that I already had these two regs and that I never used them and asked why should I spend another $300 to buy two new regs when I already had these two. I finally got them to admit that there was no reason that they wouldn't work it was just over kill as a balanced reg wasn't necessary. Now I have two O2 clean regs for my deco bottles and didn't have to spend more then $50 to get them cleaned.

Exactly, I use a DiveRite 1205 on my stage bottle, because I had it laying around and it was dirt cheap to buy.

 

[edp]

it all depends what you are doing - it is like buying a car - are you racing, transporting, commuting etc. Depth is the relevent factor here.
If you are a trimix diver then brass and glass takes the pressure better. If not then any guage is OK to be honest but needs cleaning obviously.
Short hose / long hose - up to you - the idea behind short hose is to reduce clutter and it is all you need as you can double it back and tie wrap to your first stage so it is easy to see. Long hose - only needed if you cannot see the short hose ! Im assuming you are trained up for deco, but just on the offchance you arent then dont do it, and if you havent dived with stages, twins etc on a course then take one or learn from someone experienced - seen too many accidents on the teach yourself road !!
good luck

 

[wedivebc]

it all depends what you are doing - it is like buying a car - are you racing, transporting, commuting etc. Depth is the relevent factor here.
If you are a trimix diver then brass and glass takes the pressure better. If not then any guage is OK to be honest but needs cleaning obviously.
Short hose / long hose - up to you - the idea behind short hose is to reduce clutter and it is all you need as you can double it back and tie wrap to your first stage so it is easy to see. Long hose - only needed if you cannot see the short hose ! Im assuming you are trained up for deco, but just on the offchance you arent then dont do it, and if you havent dived with stages, twins etc on a course then take one or learn from someone experienced - seen too many accidents on the teach yourself road !!
good luck

So how much does your shop charge to O2 clean a SPG?

 

[teckhead]

If for whatever reason you do run short on deco it would be better to know in advance than to begin to notice great breathing resistance then your last breath from the tank. This is not a conversation about what to do to ensure this never happens of course but if you ended up at this point. I would personally prefer to know by looking at my gauge to decide how much time I should spend returning to my backgas for decompression.

--Matt

well said Matt
i,m with you on this