custom o-rings

[Couv]

Most of my experience with o-rings not associated with scuba was on military airplanes. Therefore I usually order o-rings using a NSN (National Stock Number) or something similar. For instance, if I wanted a Viton -010 with a duro of 70, I would order a M83248-1-010. M83248 is military grade FKM then -1 = duro 70 followed by -xxx size. For duro 90 middle number is a -2-) Similarly, NAS1613 = series part number = EPDM e.g.. NAS1613-010. (NAS = National Aerospace Standard)

I know this does not answer your question, but perhaps when using AS568 that is the difference between the 1- and 2- numbers.



Couv

 

[HenrikBP]

Thanks for the clarification guys. So in short the -1, -2 and -3 numbers are similar in size based on SAE standards. And then there are special situations such as custom o-rings or Mil spec where the prefix indicates other qualities.

Thanks again. I'm diving this weekend but will place an order beginning of next week and let you know total cost etc.

Henrik

 

[Luis H]

Henrik

Thanks for the message. I don’t have a real strong need for the poppet O-rings, but if you are going to order some I will be glad to contribute about $5 (plus shipping) toward however many that would buy.

I have converted most of my 109 to BA and they seem to work great without much need for regular service. Therefore the replacement parts that I have will probably last me a while, but extra O-rings never hurt. I also have fairly good access to parts from a couple of dealers.

Thanks

 

[halocline]

I'll be happy to contribute $5+ shipping as well. Now that I have a stash of balanced poppet seats, I can rebuild my BAs using these o-rings. Mostly I'm using D300s these days, and actually finally found separate seats for those, so I'd like to get some balance spool o-rings for those. I have no idea what size they are, I could look it up I guess.

To the OP; I have surprisingly little interest in finding a reg that breathes better than the D series; those are basically like breathing on land. In fact, I'll often willingly give up a little ease of breathing to use my B/As or my PRAM just because I like them. Next time I dive to 1200ft with five of my closest friends on one reg I'll let you know!

 

[HenrikBP]

Alright, I'll get an order going today or tomorrow.

So for the 40-87 o-rings (Item # 40-87, All O-Rings (Actual Dimensions) on Precision Associates, Inc.) I have:

Couv: $10 worth plus shipping
awap: $5 worth plus shipping
Luis: $5 worth plus shipping
Mattbou: $5 worth plus shipping

Matboy; can you recommend a good source for the seats - or is it a question of good connections ?

Henrik

 

[halocline]

I got the seats from a shop that I occasionally DM for, I didn't even know they had them.

 

[redacted]

Alright, I'll get an order going today or tomorrow.

So for the 40-87 o-rings (Item # 40-87, All O-Rings (Actual Dimensions) on Precision Associates, Inc.) I have:

Couv: $10 worth plus shipping
awap: $5 worth plus shipping
Luis: $5 worth plus shipping
Mattbou: $5 worth plus shipping

Matboy; can you recommend a good source for the seats - or is it a question of good connections ?

Henrik

I'm good for $10 if needed. I have gotten the balanced poppet seats from my source - about $3 each. I'll take an old D-sereies poppet apart and measure that o-ring. It looks like 1mm wide and about 4mm ID. I have some 1 x 5 orings that I can compare it to.

 

[HenrikBP]

Thanks guys. I'll ask some of my local shops about seats.

awap; I need a few other o-ring sizes so I think we're fine with the minimum purchase. So $5 or $10 is up to you - no problem either way.

Henrik

 

[redacted]

Thanks guys. I'll ask some of my local shops about seats.

awap; I need a few other o-ring sizes so I think we're fine with the minimum purchase. So $5 or $10 is up to you - no problem either way.

Henrik

Then $5 it is.

 

[HenrikBP]

I ordered $35 worth of the 40-87 and that got us 140 o-rings. So each $5 gets you 20 o-rings for a cost of $0.25/o-ring. They couldn't give me the shipping cost until the order goes out tomorrow. I'll post an update then.

Henrik