Regulator attachment details

[mxracer19]

Ill be getting my regulators and guages and whatnot soon and I only have 1 question.

Do I need to know anything specific about attaching my spg and octo to my 1st stage? Or do these things just screw in? My mechanical side says just screw them in with some oxy-compatable grease...but my safety side says to ask. And what is a good tourque setting? finger tight with a 1/4 turn?


Thanks
-Matt

 

[Scottri]

They just screw right in. Be careful not to tighten them up to tight. Snug them down lightly. Let the O-ring do it's job. Just coat the o-rings very lightly with a silicone grease until they are shiny. Not much is needed.

 

[DA Aquamaster]

They just need to be snugged very slightly past hand tight. 1/4 turn is WAY too much and will cause the fitting to separate as the threads will be stretched.

Tighten them with a short wrench and/or choke way up on the handle so that your hand is right next to the fitting to minimize the amount of torque you can put on it.

As indicated above, the o-ring does the sealing, you just need it tight enough so that it does not come loose from normal handling, etc.

 

[mxracer19]

Thanks guys.


-Matt

 

[M_Bipartitus]

I was thinking about the torque issue a few weeks ago and as it has come up...

Are there any manufactures that state a suggested torque to tighten connections to? and if so what value?

 

[DA Aquamaster]

Scubapro specifies torque values for nearly everything but with regard to hose attachment only specifies what is described as "tool tight" which is effectively what I described above to use a wrench to go only very slightly beyond hand tight. It seems to to be the industry standard.

One issue with torquing a hose fitting is that you would have to use a crow's foot and adjust the torque value accordingly. The torque amount is (or should be) so small that things like o-ring hardness and lubrication would affect it. And evena small, but still relatively long torque wrench on the fitting is potential problem as poor technique, a faulty setting or a mis calibrated torque wrech could cause big problems. It's one of the few application where, in my opinon, feeling what is going on is more important.

The important thing is to have the fitting full seated to fully enclose and contain the o-ring and it needs only be tightened enough to prevent it from coming loose under normal handling. I like being able to "feel" how the o-ring is seating when tightening one. The threads themselves on most fittings are very fragile as there is not much metal left between the hole in the fitting and the bottom of the threads and they can easily separate if over stressed.

I serviced a first stage a couple weeks ago where the primary regulator hose literally came off in my hand while pulling the hose protector back to expose the fitting. The owner had excessively tightened the fitting with the result that he had effectively separated all but the top two threads and the pulling movement on the hose was enough to cause the remaining two threads to fail. He indicated he had not used the reg since moving the primary to a different port and I advised him he was very lucky as a failure in the water would have resulted in a spectacular freeflow that would have emptied his tank in about a minute.

 

[Queen]

I'm not much of a techie but this stuff is fascinating! I've always been too scared to trust my life to my own (sadly lacking) mechanical abilities but I think it may be time to learn.

 

[Greg Barlow]

Ill be getting my regulators and guages and whatnot soon and I only have 1 question.

Do I need to know anything specific about attaching my spg and octo to my 1st stage? Or do these things just screw in? My mechanical side says just screw them in with some oxy-compatable grease...but my safety side says to ask. And what is a good tourque setting? finger tight with a 1/4 turn?


Thanks
-Matt

The advice that DA Aquamaster gave is right on the money. I have serviced way too many regs that had overly zealous owners tighten the fittings to the point of damaging the fitting. A quarter turn on a hose beyond finger tight would probably result in at least 15 pounds of torque, and would likely cause damage to the first stage body or fitting.

Greg