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#756
octo as a primary?
Sonnylynnvick75 - 4/16/2014 10:33 AM
Category: New Diver Q&A
Replies: 21

As I’m fairly new, I figure this is a viable question. Is there any difference in the capabilities of a primary and an alternate second stage? The reason I ask is I have a back up alternate 2nd stage (scubapro r290) (I primarily use air2). I’m curious as to the usage of this back up in certain situations, for instance, My primary reg fails can I swap my back up alternate 2nd stage in place of my primary 2nd stage?
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Greg - 4/16/2014 11:22 AM
Usually alternate regs aren’t made as nice as primary regs, cheaper parts. Primary regs usually have more features (balanced, adjustment knobs, venturi switch, etc.).

That being said...I rented gear one time, and the alternate reg breathed much better than the primary reg...so I used that during the dive. I made sure to tell my dive buddy what I was doing using hand signals. I pointed to my primary and signaled "something is wrong", then I pointed to my alternate and signaled "ok". The primary still worked, it just took more inhalation effort to breath.
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LatitudeAdjustment - 4/16/2014 12:22 PM
In the beginning they were the same but as the primaries got better and breathed easier the 2nd had to be de-tuned so they wouldn’t freeflow. The reg on my stage bottle is a primary but its presurized and then turned off until I need it.
If you go to scubadiving.com and look at scuba lab you can see the breathing test for the regs, some of the 2nd’s don’t breath easy at depth so if you are thinking of going into tec later I wouldn’t buy say a Sherwood Shadow now.
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John_giu - 4/16/2014 5:47 PM
You could but I would STOP diving until I replaced the primary.
The only reason to have to Octo is to save your life should your primary fail.
If I understand you correctly?
#756
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Sonnylynnvick75 - 4/17/2014 5:20 AM
Let me reword my question with a scenario:

I go diving at one of the local quarries, I have a plan set for 3 dives throughout the day. On my first dive of the day my Primary fails. I make an ascent using my air2. I return to the picnic tables and remember that I have a spare octo in my save a dive kit. Instead of calling it quits for the day, I replace my failed primary with my spare octo. In this scenario I would always have my air2 as my emergency air supply, I would only be replacing a failed primary with my spare octo.
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LatitudeAdjustment - 4/17/2014 6:49 AM
From Sonnylynnvick75: I would only be replacing a failed primary with my spare octo.

Totally legal, no one will call the Scuba Police!
#756
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Sonnylynnvick75 - 4/17/2014 7:11 AM
From LatitudeAdjustment: LatitudeAdjustment - 20 minutes ago.
From Sonnylynnvick75: I would only be replacing a failed primary with my spare octo. Totally legal, no one will call the Scuba Police!

More or less just curious if this was viable option in the event something did happen.
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Eric_R - 4/17/2014 5:02 PM
I’m still diving with the same regs I bought in 1987 and they work great! I have an MR12III and a Mares MR12 V Octo that I will often switch during the dive to make sure their working properly. I’ve used them for everything from the Caribbean to ice diving here in Mi and have never had a problem.
#7352
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UWnewbee - 4/17/2014 8:27 PM
From Sonnylynnvick75: More or less just curious if this was viable option in the event something did happen.

dont take this the wrong way,, but what do you think your octo is actually for?? my next thought is if your not sure if you can use your octo in a emergency,, did they not go over this in your class?? every class ive seen this has always been covered
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bronxdiver - 4/17/2014 10:22 PM
I use to have the Scubapro MK2/R295 and Octo R295, they are the same regulator, except for one being yellow and having a longer hose. That being said i dnt see why u couldnt use it as a primary. Some octo’s dnt breathe as well as a primary but u are still supposed to be able to use it and breathe thru it. I have seen divers who use an octo as a primary also. Dnt see the need to STOP and wait till u get ur primary fixed. Might not be broke, Maybe ur octo is a great breather and u use an air source as ur octo or u have ur primary hooked up to a different rig and ur just configuring ur gear this way for ur current circumstance.
#756
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Sonnylynnvick75 - 4/18/2014 5:12 AM
Uwnewbee. Re read my scenario. Obviously I understand an octo is used in an emergency. I understand an Octo is just another regulator. I’m not asking if it can be used as an emergency device. I’m asking if it is capable of long term usage(more than an ascent to the surface) and if it is basically the same quality as a primary as a replacement
#2632
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John_giu - 4/18/2014 7:31 AM
By The Way,
I usually take a least a few puffs from my Octo before EVERY dive just to be sure it will be there if I need it. Some times while diving I’ll switch just for the practice. I like my Mares Abyss 42 but the MR12 octo breathes just fine, as other posts have noted. Not all octopus are junk regs that breath poorly.
#7352
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UWnewbee - 4/18/2014 8:59 AM
From EskimoBluDay: Geese dude. Do you even read the OP’s post before being condescending? Do YOU know what an Air2 is, what it’s for, & how it’s used?

Gee dude did you see the Only point i commented on in a quote? Yes i Know what a air2 is!! Dude I think im gonna nominate you as the forum police
#7352
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UWnewbee - 4/18/2014 9:32 AM
some that i know of use regs that are both primarys others have primary an octo, most i know of including myself will switch only in a emergency to surface and end the dive, I myself travel with 2 complete reg set ups and have swapped,, but i myself dont think its a wise idea doing on site repairs as 1 grain of sand or water can ruin your whole day or the possibility of worse happening
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Eric_R - 4/18/2014 12:27 PM
Has anybody every seen a reg fail where it didn’t supply air when there was still air in the tank? Maybe a first stage. They are of sound design otherwise you would be diving with a complete spare setup all the time and would have been taught to do so in class and this sport would not be what it is today. The cheaper regs may not preform as well at various depths and temps but it will supply you air.
#7352
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UWnewbee - 4/18/2014 1:00 PM
I actually witnessed a diver swap both regs from hose to hose not realizing the valve seats were broken in for each one and possibly different,, as soon as he charged the line one free flowed an the other didnt work,, we told him to undo what he did and everything was fine,, why he did the swap we had no idea
#2632
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John_giu - 4/19/2014 8:18 AM
From Progrower: Progrower - 19 hours 48 minutes ago.
Has anybody every seen a reg fail where it didn’t supply air when there was still air in the tank? Maybe a first stage. They are of sound design otherwise you would be diving with a complete spare setup all the time and would have been taught to do so in class and this sport would not be what it is today. The cheaper regs may not preform as well at various depths and temps but it will supply you air.

TRUE,
They are designed to "FAIL OPEN". Or, to put it another way, they are "NORMALLY OPEN, or flowing" But I still would not dive without a working octo.
#756
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Sonnylynnvick75 - 4/21/2014 3:31 AM
From Progrower: Has anybody every seen a reg fail where it didn’t supply air when there was still air in the tank? Maybe a first stage. They are of sound design otherwise you would be diving with a complete spare setup all the time and would have been taught to do so in class and this sport would not be what it is today. The cheaper regs may not preform as well at various depths and temps but it will supply you air.

I was referring to "fail" as a free flow or a second stage being stuck open. I understand Second stages have a fail-safe in that they are designed to free flow or stay open should something mishap, but I would personally rather use a properly working second stage to continue my dives throughout the day.
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diverray - 5/10/2014 4:23 PM
My interpretation of your question is that you still have an emergency backup (Air2), and have changed your primary second stage from a black one to a yellow one. I see nothing wrong with this, other than as noted above that many of the yellow ones don’t breathe as easily. Unless I’m missing something, I don’t see a safety issue here?
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MDW - 1/24/2015 8:52 PM
My opinion is there is no such thing as an "Octopus" since A) it only has one hose, not eight (LOL) and B) a second stage is a second stage. Your primary second stage is the one in your mouth and your secondary second stage (or what some people inexplicably refer to as an "octopus") is the other one that’s not in your mouth. Ideally, you would just have 2 of the same one so it doesn’t matter which one is in your moth at any given time.