Freeflow at 100fsw

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Sounds like you did an excellent job of handling the situation.

There is always some controversy about using an octo-inflator. I have used one for years and I have never had a major problem with mine (SP Air II). I have used mine in an OOA emergency. It worked just fine and I donated (actually the guy took) my primary. I test my Air II on nearly every dive. The Air II can be touchy if you get sand in it and it can be easy to freeflow if it isn't adjusted correctly. If I do a shore dive, I take the cover off and rinse it thoroughly after the dive. If I don't, it will surely freeflow due to sand being in the diaphram.

I know not everyone likes them, but the octo-inflator I use is my choice for an octo.
 
One thing you can do to check the tuning of a reg is to put it in the water mouthpiece up, and slowly lower it until it starts to freeflow. It should be about halfway up the body when it starts or 2.5 cm/1 inch deep.

This freeflow situation is one reason I dont really like the adjustable second stages.
 
For rec diving, the octo is great. If I need it, I know exactly where it is, because I use it all the time for buoyancy and quacking. It actually gets less abuse than my primary because it is so short and because of its location. It breathes differently than my primary, a little wet and noisier.

For tec diving, analog pressure guage, primary and secondary.
 
James Goddard:
Would you consider this a fair assement to sum it up?:

Because you practice (something many divers do not do), sharing the octo with the dump valve was not a major inconvience. However, the shorter hose for sharing was an inconvience and probably was the source of the twirling you described?

I would say that is a fair assessment.

--Dan
 
If it is a 2nd stage free flow, an Apeks Free-Flow Control Device would help.

Of course, it is only fix-gap solution to the problem (i.e. adjust your IP and crackling effort correctly), but in a fix, the Apeks FFCD is a possible solution.


-BubbaFetta
 
pufferfish:
It would seem to me that if the purge button was accidentally pushed or the resistance knob dialed all the way out one would always get a freeflow.

I have the same regs (Legend LX Supremes). So long as the reg is in your mouth, you don't have to worry about free flow. If it will happen at all, they will not free flow unless dialed all the way and out of your mouth and purged, etc. Even in this situation, I have never had this happen if I have the mouthpiece down below the purge button, i.e., facing down. This is the reason that a proper primary regulator hand off includes removal, aiming the mouthpiece down until in front of your buddy, if possible, and then turning the mouthpiece toward your buddy's mouth as it arrives in front of his/her face.

On the other hand, remember about the dangers of CO2 build up due to work of breathing. You want an easy breathing, high performance regulator to minimize this problem. This may not seem like a big deal in shallow water but gas density will increase when diving deeper. Add harder work due to current, etc., and it becomes even more important to use a top performer. Overbalancing and proper adjustment will keep gas flowing with the least work of breathing, which is the goal.

These regs not only have the dial knob but also have a +/- lever. Just move the lever to "-" if you are going to clip off to your d-ring for deco, etc. Purging will not cause free flow at that point. After some practice, you can take the reg out of your mouth and flip the lever easily and quickly. In the end, there is no problem but you still have a top performing reg when you need it (as opposed to designing to avoid free flow situations at the sacrifice of ease of breathing).

When I have hit the purge with the reg out of my mouth underwater, I have never had a free flow issue with them even dialed all the way to easy breathing. The only remotely similar thing happened to my backup when dialed to easy breathing but levered to "-" when being towed behind a scooter in a strong head current. I just adjusted knob a little in addition to the lever at the first sign of flow; end of problem.

I have never had a better performing regulator. I practice a lot of out of gas/sharing drills and my reg is easier breathing than any other I have used, in my side by side drills, underwater. I am sold on them.
 
Thanks SDM. So reduced WOB which should reduce the risk of CO2 buildup seems to be the reason. This probably comes at the expense of a slightly higher risk of second stage fleeflow in very cold conditions. The reason I asked this was my LDS had detuned my Apeks slightly for ice diving and after they put it back to spec for the other three seasons I noticed it was cracking slightly harder than my buddy's LX Supreme when previously they had been the same. Took it back and asked them to reduce the cracking pressure some more to the point it free flowed slightly dialed all the way out.
I have not had a problem with a ff since except once on the point when I hit the purge accidentally with the system charged. No longer have the desire to use my buddy's Aqualung but they are very nice regs I must say.
 
https://www.shearwater.com/products/swift/

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