Torque for Atomic DIN conversion

[twinkles]

I am thinking about converting my Atomic B2 to a DIN fitting. What is the proper torque for the DIN fitting on an Atomic Regulator.

And if I should go back to the Yoke fitting what is the proper torque for the yoke nut?

Last question (probably not) but where could I buy a yoke nut for my Atomic B2?

 

[paulwlee]

33 ft/lbs for both DIN and yoke fittings.
Your Atomic dealer should be able to get the yoke nut for you. Did you scratch it up?

 

[twinkles]

yep scratched it up.

 

[DA Aquamaster]

33 ft/lbs is a lot compared to similar designs.

 

[paulwlee]

That's what I noted down from the manufacturer(Atomic) parts list/diagram, after which I triple checked. But I don't have the documents myself, so if someone else does, please feel free to confirm.

I see on one manufacturer service manual I do own, that Aqualung Titan first stages require 20 +-2 ft/lbs for DIN and yoke fittings, in the same general range, considering it's a different make/model.

 

[Flightlead]

tight is tight....loose again is too tight!

Seriously, 33 ft/lb seems excessive to me. And I'm confident based on measurements on the three that I recently converted using my my SAE calibrated elbow that the manufacturer installed yokes were not at that high a value.

I just snugged them up finger tight then added a good nudge with a wrench (boy, that's an accurate engineering measurement, eh?) I certainly didn't get anywhere near spark plug torque (32 ft/lbs was what I always used). I've dove them all successfully down to 140 fsw with no problem.

 

[DA Aquamaster]

Scubapro for example uses a narrow range centered around 22 ft lbs for the yoke/DIN retainer and as noted above Aqulaung is in the same 20ish ft pound ball park.

Take an extra 9 to 11 ft lbs of torque, add saltwater, some O2, and some time and you get 33 ft lbs plus whatever is required to break loose the corrosion and things can get interesting when it comes time to take thing apart.

But, Apollo's specs are Apllo's specs, I'm just really interested in hearing the rationale for that much torque.

 

[paulwlee]

I just snugged them up finger tight then added a good nudge with a wrench (boy, that's an accurate engineering measurement, eh?) I certainly didn't get anywhere near spark plug torque (32 ft/lbs was what I always used). I've dove them all successfully down to 140 fsw with no problem.

Human perception is notoriously inaccurate especially with respect to force.
I read about a study somewhere about experienced mechanics tightening bolts to what they thought were the right specs by feel, and they were all over the map.
Since your work setup and body position is very different when you are tightening your spark plugs, I don't think it makes for a good basis for comparison.
Also, the fact that you dived it to 140ft doesn't really matter. I'm quite sure there is a large proportion of regulators out there that are torqued to anything between 30%~%300 of the manufacturer recommended torque spec and seeming to work just fine.

But again, since there are two people expressing skepticism and since I now don't have access to the documents, if there is anyone who can verify my number, I'd be grateful.

 

[Flightlead]

Human perception is notoriously inaccurate especially with respect to force.

human perception is notoriously inaccurate, period

anyway, I agree with you the right answer is to look in the manual.

 

[rakkis]

You really shouldn't be messing around with that stuff if you're unsure about the proper way to do it.