My reg stages are so old I can't even tell who manufactured them so I just join together the ones that work...
Why can we not mix first and second stages from different brands?
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Sorry you are all wrong. The scuba gods will bring down hell and wrath should you mix brands. I thought about it once and the sky clouded over and the waves picked up to a hurricane level.
I quickly erased those sinful thoughts from my head and in penance went and bought 2 full Oceanic reg sets with matching fins and mask and a calm descended over me once again (I think Scubapro will do the same thing?).
Also I have heard if you mix brands, they will self combust under water. Something to do with the square root of half twice its diameter being excessive to the brand (all too technical for me to really understand).
So when you look at second hand gear and are considering mixing brand, resist the urge to save money, respect the manufacture gods wishes and put all your trust and (more importantly) money in their hands so you follow their divine advertising spiel.
OR
You could just risk it and chance saving money by using what you already have like 95% of everyone else here YOU BLOODY HEATHENS.
I quickly erased those sinful thoughts from my head and in penance went and bought 2 full Oceanic reg sets with matching fins and mask and a calm descended over me once again (I think Scubapro will do the same thing?).
Also I have heard if you mix brands, they will self combust under water. Something to do with the square root of half twice its diameter being excessive to the brand (all too technical for me to really understand).
So when you look at second hand gear and are considering mixing brand, resist the urge to save money, respect the manufacture gods wishes and put all your trust and (more importantly) money in their hands so you follow their divine advertising spiel.
OR
You could just risk it and chance saving money by using what you already have like 95% of everyone else here YOU BLOODY HEATHENS.
thre is no problem interchanging regs ....per sa if the ip is close eg Poseidon regs are to high to work well with Sherwood .......
Scared Silly
Contributor
I once saw some once try to put an Atomic second stage on a ScubaPro first stage. You should have heard the squealing.
Jokes aside there are a few that second stages that should not be interchanged, namely ones from Poseidon which are upstream and should only be match with a particular first stage I think the Xstream. I can not recall all of the details. Do a search ...
Jokes aside there are a few that second stages that should not be interchanged, namely ones from Poseidon which are upstream and should only be match with a particular first stage I think the Xstream. I can not recall all of the details. Do a search ...
You could find an ancient tilt valve second stage and install that on a more modern first. Then if there was an IP runaway you would get to experience an LP hose burst. Those first stages would have had a over pressure release.
As far as I know, nobody ever said you could not mix and match except for the very few as has been mentioned due to speical design considerations. The SP109 is great on the Conshelf first. I use Tekna/Oceanic MkV clones in place of SP MkV firsts.
Most second stages can operate decently (when tuned) with an IP between about 115 to 150 psi (150 is kinda high) with around 130 being typical in their manuals. Set the IP to this nominal value and then tune the seconds (cracking force) to that setting and go dive. Regulators set for cold water diving sometimes set a slightly lower IP, typically around 125 or so.
It is not really complicated.
N
As far as I know, nobody ever said you could not mix and match except for the very few as has been mentioned due to speical design considerations. The SP109 is great on the Conshelf first. I use Tekna/Oceanic MkV clones in place of SP MkV firsts.
Most second stages can operate decently (when tuned) with an IP between about 115 to 150 psi (150 is kinda high) with around 130 being typical in their manuals. Set the IP to this nominal value and then tune the seconds (cracking force) to that setting and go dive. Regulators set for cold water diving sometimes set a slightly lower IP, typically around 125 or so.
It is not really complicated.
N
gcarter
Contributor
Although it is a fashion faux pas, the lower classes have been mixing first and second stages for decades with no apparent ill effect.
You just want to make sure that the second stage(s) are downstream models. This includes virtually all except some Poseidon units. The common downstream second stage also acts as an over pressure relief in case the 1st stage is creeping or in free flow. Lacking that a relief feature is needed.
Other than that tune the second to play with the 1st and go dive.
Pete
Other than that tune the second to play with the 1st and go dive.
Pete
Grocio
Contributor
My first stage is a Sherwood and my alternate second stage an Aqualung. I've had no problems so far.
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