Turret or Swivel on Reg??

[DIVERDREW]

Zeagle makes a DS4 non swivel first stage and a 50D swivel style first stage. The internal components are identical in these first stages but the 50D is basically a DS4 with swivel or turret LP ports to give the diver alternate hose routing options. My question is, do you feel the swivel or turret on the first stage adds an unacceptable failure point to the regulator or is this point a non issue?

Thanks in advance for the feed back
Drew

 

[drizzt117]

Some would say that it definately adds an unneeded failure point, and I tend to agree with them. I just don't like swivel 1st stages, so its a non-issue for me b/c I wouldn't use it anyway.

Thomas

 

[metridium]

Had a Mk20 swivel failure just before entering the water once...ostensibly due to poor maintenance. It was one month away from its next annual inspection at a Scubapro-approved facility.

Since then, I either dive with redundant first stages or with a trustworthy buddy otherwise. The Mk20 will be phased out to eventually become a stage regulator.

 

[DIVERDREW]

Can anyone quantify the likely hood of this failure point? I agree that the turret does creat another possible failure point, but can anyone tell me the likelyhood of this failing? Even a 5th LP port addes another possbile failure point as it is also a oring failure point, but I don't consider this even worth consideration as the likely hood of failure is so minute. The turret however is not a static failure point which may make it a higher risk area? Thoughts? Has anyone ever had this type of failure on a reg??

Drew

 

[DIVERDREW]

metridium thanks, I must have just posted the second question just after u posted your response. That is my thinking also, to eventually move this reg to my deco bottle from my back gas. Right now it is on my left post as my backup reg on doubles.

Drew

 

[ElectricZombie]

I do not think it adds a failure point IF the reg is properly re-assembled after servicing. I have 3 turret 1st stages and have had no problems at all.

Here at the University, all we use are Mk20/Mk25 regulators. We probably have 30 - 35 of them and have never had a problem with the turret.

 

[DIVERDREW]

Thanks Zombie
I looked up the schematic for the reg and there is one more internal oring than the DS4. I have never had the reg apart myself but am curious to see how the swivel moves over this ring, it sounds as though the swivel turret is not much of a failure point issue however in the grand scheme of things. I know JJ uses the SP swivel and GI uses the flathead or TX100 nonswivel.

Drew

 

[redacted]

the turret O-ring is fairly substantial, is on the LP side, and is reasonably well captured. While all o-rings represent a failure point, I don't believe this one is any special problem. And its failure, while dive endings, should not be life threatening.

Serious potential problems comes with the turret bolt (swivel retainer) if not properly torqued. The torque specification is 70 inch pounds (about 6 ft-lb). Over-torquing this bolt can cause thread failure which can lead to catestrophic failure. I have seen past threads on this board that have suggested some dive shops will replace this bolt anytime they rebuild one of these regs of unknown background. Not really sure what good this does as I suspect the shorter run of threads in the swivel (turret) may be the more vulnerable point. In any case, it's probably a good idea to make sure your tech has & uses a torque wrench (another sensetive subject) and inspects these threads for any sign of stress of fatigue.

While I'm not familiar with other regs, I suspect this holds true for most if not all turreted 1sts.

 

[DIVERDREW]

AWAP
Thanks for the tips, that will be useful information when it comes time to have the reg serviced. I am popping into the dive shop today so I might try to bring up the torque wrench issue without offending the owner ;-)

Thanks Drew

 

[metridium]

awap wrote...
the turret O-ring is fairly substantial, is on the LP side, and is reasonably well captured. While all o-rings represent a failure point, I don't believe this one is any special problem. And its failure, while dive endings, should not be life threatening.

Even on a catastrophic failure? On a 100' solo dive, for example?

When mine failed, it was moving some serious air. I have nothing to compare it with, so perhaps it sounded much worse than it was...but I suspect it wouldn't have taken long to drain the tank.