Scubapro R109 and O2 Cleaning

[smorneau]

I have a R109 that I would like to use as a deco reg for 100% o2 for my up coming Adv. Nitrox/Deco class. I need to O2 clean it.

I am going to wash it in my ultra sonic cleaner with simple green and use cristo lube where needed and change the o-rings to vitons. Is there anything I am missing? Is the seat ok to use with o2? What sizes are the o-rings that need replacing?

Thanks

 

[halocline]

You do mean the metal case 109, right? Not the plastic R190?

Anyhow, I guess you could find a sheet of viton or some other fluoroelastomer to stamp seats out of, I don't think you can buy viton seats. There's only two o-rings, 902 for the orifice and 011 for the adjustment knob.

Why wouldn't EPDM work? It's not a high pressure situation.

 

[smorneau]

Are the ones we are getting from Vintage Double Hose EPDM?

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[smorneau]

Yes I mean the all time great 109!

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[DA Aquamaster]

If you are talking about the R109 second stage, O2 cleaning is a complete waste of time. It's won't stay O2 clean and there is no need to O2 clean the second stage beyond normal cleaning anyway as all it will see is O2 at intermediate pressure.

The first stage, whether it is a Mk 1, Mk 2, Mk 3, Mk 5, Mk7, Mk 8, Mk 9, Mk 10, Mk 15 or Mk 20/25, is what needs to be O-2 cleaned.

Viton o-rings have a higher ignition temp, but EPDM o-rings are also suitable for O2 as their ignition temp is well above that of Buna-N / Nitrile rubber o-rings, and they wear a lot better in dynamic applications than Viton O-rings. Plus if you do get an O2 fire in the reg, Viton produces phosgene gas when it burns - that was on of the favorites used in gas attacks in WWI. It's a long shot but the residue of that is not something I'd want to breathe if I had a flash fire in a first stage.