Scubapro O-ring Sizes

[Zung]

I attempted to place an order last week while in L.A., here's what I've got:

"... we have cancelled your order for these washers.
Due to the cost of complying with extensive US export regulations, McMaster-Carr accepts international purchases only from our established international customers..."

And I've ordered stuff from them before!

 

[guruboy]

Never mind. Found the 5-179 at theoringstore. Had been shopping at oringsusa

 

[AFdivedoc]

I attempted to place an order last week while in L.A., here's what I've got:

"... we have cancelled your order for these washers.
Due to the cost of complying with extensive US export regulations, McMaster-Carr accepts international purchases only from our established international customers..."

And I've ordered stuff from them before!

I had this issue with them when I was stationed at a US base in Japan. They would not ship there even to a US post office box, and I had previously ordered from them many times before. We're talking small quantities for personal use, and not trying to establish an o'ring dealership! It was a bit frustrating.

 

[buddhasummer]

interesting, the site used to let me look but now it says I need an account. I wonder if it caught my IP address...

 

[buddhasummer]

I attempted to place an order last week while in L.A., here's what I've got:

"... we have cancelled your order for these washers.
Due to the cost of complying with extensive US export regulations, McMaster-Carr accepts international purchases only from our established international customers..."

And I've ordered stuff from them before!

Guess you're not deemed "established" enough, that sucks.

 

[Couv]

Another example of "The Establishment" keeping the man down.

 

[herman]

Oh trust me, he's not keeping the budda down.

 

[Wayward Son]

so, best I can tell from this thread is that the 2.5mm o ring works OK on the S wing poppet in place of the 2.2mm that's hard to get here.

I have found a european source, works out to about $0.21 / o ring for 100 qty cans before shipping. I haven't yet found a source for them domestically.

NBR 70 SOFT 2.20 X 1.00 -O-rings for Scuba Diving

at $0.04 each, this is the lowest price on the 2.5mm I've found:

1mm X 2.5mm Metric Buna-N 70 O-ring [N1.00X002.5] : The O-Ring Store LLC, We make getting O-Rings easy!

 

[Zung]

I'd rather stick to the proven, see my previous post :

• 2.2mm for the dual o-ring poppet
• 2.5mm for the single o-ring poppet

You've got a good source for the 2.2mm; depending on how many you want/need, the price is OK'ish, or start a group buy.

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

 

[rsingler]

I was holding back, but I can't resist.
Got the microscope out, and compared 01.050.363 with my replacement 1mm x 2.2mm Viton 70
From mold marks to size, these o-rings are nearly exact matches.
Don't know if SP uses EPDM, but the duro 70 vitons feel identical and they perform flawlessly.
Precision Associates 70 Duro Black Fluoroelastomer .040 C/S x .087 ID x .167 OD
1-800-394-6590
But no, they're not 4c apiece.
For my money, the identical surface configuration with the 363 on this critical part made the choice easy.

Viton 1x2.2 on left, SP 363 on right; 30X magnification