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Scuba fitting specifications

Anyone know the dimensional specs for the 3/8-24 and 7/16-20 straight threaded fittings used on scuba regulators and hoses? I don't mean the inside and outside threads themselves (they are UN spec), but the face that mates to the O-ring. There are several steps in the face of the female fitting which I would like to be able to machine myself.

It may be something like SAE J514, but that's not quite right.

See "HP & LP Scuba Adapters" here for some (fuzzy) photos:

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Here's 7/16-20 hydraulic adapter that looks like a male scuba fitting (the O-ring side on the right, not the flared end):

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Grainger just calls this "SAE standard", and I'm not sure if this is the same as used for scuba or not.

Reply to
Richard J Kinch
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Most likely one of these three: MS(like MS33649) or AN (like AN10050) or SAE (either 514 or 5202)

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We usually cut them with porting tools from Wetmore or Tosco.

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Reply to
tomcas

Try "rec.scuba.equipment" or "rec.scuba"

Reply to
Gary Owens

Yeah, I figured some metalworking types would be more likely to know the technical details. The rec.scuba.* is about brand X vs brand Y, not about what you make in your own shop.

Reply to
Richard J Kinch

Your references above all have 120 degree beveled cuts on the outermost step; the scuba fitting has only a square step.

Here, I made a drawing of my measurements that have worked for me, although I would like to have the actual specification:

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Reply to
Richard J Kinch

Let me correct what I said above. After examining some typical ports, it is apparent that they do have a bevel or taper where the O-ring seats on the female side.

I've thoroughly Googled and Deja'ed this issue and I can't seem to find any hits at all on it, other than some non-specific comments about the fittings being "SAE".

Reply to
Richard J Kinch

If you take some rough measurement and post back with them it would help.

Reply to
tomcas

Again answering my query after some more searching, it seems that the SAE J1926 standard seems to match well. This was reproduced as a military standard MS16142 which is available at

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although this has been cancelled in favor of just referencing the SAE document (which costs $$ to download).

Reply to
Richard J Kinch

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