Scubapro O-ring Sizes

[Wayward Son]

I have found VDH to be an very valuable resource. Service kits, parts -including replications of ones no longer made- service kits, videos, there's a LOT to support people there.

 

[Fibonacci]

Anyone know the correct o-ring sizes for the older brass-and-glass Scubapro SPG spin-off lens holder to body?
Seems there are at least two face sizes, a smaller one that could be used with an adaptor to fit the console, and a larger one that fitted straight into the console.

 

[Couv]

I've never seen one of those seals fail, however if you are bound and determined to replace them take the gauge to a hardware store to find a match. Then order the a quality seal of the correct size.

Judging from an external measurement only, my best guess would be a -035.

I'll be interested to hear your findings.

 

[Fibonacci]

Thanks Couv
I tried to unscrew one of the plated brass cover bezels by hand, and its pretty much stuck in place.
With the usual freezing and heating in hot water process I've used successfully before to free corroded-in-place regulator parts I'd say there's a very good chance of cracking the glass to fix a seal that isn't leaking!
If it ain't broke...

 

[Hawaii Treasure Finder]

Mystery solved.... maybe.

Master couv has previously measured the groves (journals) of the S-wing poppet:

• Active journal (near the balance chamber): .091"/2.31
• Wiper journal (near the LP seat): .077"/1.96mm

I measured an older poppet, the blue one with the metal stem and a single o-ring, and:

• Single journal: .0962/2.44mm

So now it makes sense... sort of:

• The current all plastic S-wing poppet with a smaller journal takes a 2.2mm, with a 5% strech
• The older poppet with the metal stem and a larger journal takes a 2.5mm, with a 2.5% oversize

Hi Zung - this may be addressed in a different thread already - but concerning the two little o-rings on the g250 poppet measuring 2.2mm x1mm, would you feel comfortable using a 2.0x1 viton 75 or would you go with the larger 2.5x1 viton 75? I ask as the site I use for all o ring orders has the 2.0 or the 2.5 but not the 2.2... (site is theoringstore.com). Thanks in advance for the feedback.

 

[Zung]

Hi Zung - this may be addressed in a different thread already - but concerning the two little o-rings on the g250 poppet measuring 2.2mm x1mm, would you feel comfortable using a 2.0x1 viton 75 or would you go with the larger 2.5x1 viton 75? I ask as the site I use for all o ring orders has the 2.0 or the 2.5 but not the 2.2... (site is theoringstore.com). Thanks in advance for the feedback.

I tested the 2.5 and it works; I don't know about the 2.0, so you have to test it yourself. And if you're still alive after the experiment, tell us all about it.

Then again, since this isn't a high wear item, it'll probably last a while and give you enough time to source the right stuff (2.2).

 

[Couv]

1.0 x 2.0mm o-rings work and are available from McMaster Carr. McMaster-Carr
However, see @rsingler 's post #280 1.0 x 2.2mm seals are available from P.A.I.

@Zung Good to see you're still among us. Don't be such a stranger.

 

[Zung]

@couv
Hey Bro, how z'it doing?
Sorry for my long absence, I've been enjoying a new hobby: my retirement!

 

[Couv]

I've been enjoying a new hobby: my retirement!

Congratulation! I'll be joining the ranks at the end of this year.

 

[Zung]

Welcome to the club!
You'll see, it's quite a change; to quote a colleague who's been there: "freedom, no stress, pay for software, miss all the colleagues, no monday morning meetings, no forecasting...", to which I'd add: pay for and tend you own car, deal with a painful drop in the income, and rejoyce at the sizeable drop in the income tax....