There are two variants of the o-ring boss port, the SAE commercial
version (J1916/MS16142) and the aerospace (AS5202/MS33649) version. For
amateur use, they're compatible but for real flight hardware, they're
not supposed to mix. The port contours are slightly different
(different o-ring squeeze) and AS5202 uses UNJF-3B (rolled threads)
instead of UNF-2B for better fatigue resistance. At least that's how I
understand it.
-Bob
On 2/7/21 1:08 PM, roxanna Mason wrote:
The 937 has o-ring boss ports.
On Sun, Feb 7, 2021 at 8:26 AM Evan Daniel <evanbd@xxxxxxxxx <mailto:evanbd@xxxxxxxxx>> wrote:
You might want to double check on the port, too; I'm used to thinking
of the AN-like o-ring boss fittings as being SAE J1926 aka MS16142,
which isn't the same thing as AS5202, though both use the same
threads. I'm not clear on the differences.
Evan Daniel
On Sun, Feb 7, 2021 at 8:28 AM William Claybaugh
<wclaybaugh2@xxxxxxxxx <mailto:wclaybaugh2@xxxxxxxxx>> wrote:
>
> Michael:
>
> Just to be certain we are talking about the same thing; this is
a four-way cross with a male o-ring boss (ORB) on each leg?
>
> If so I’d be happy to get six.
>
> Bill
>
> On Sat, Feb 6, 2021 at 5:14 PM Michael Clive <zeinin@xxxxxxxxx
<mailto:zeinin@xxxxxxxxx>> wrote:
>>
>> I have many of them we don't use. I can box them up and ship
them to you for a nominal fee, like 5 bucks each.
>>
>> Allan aircraft makes them for hundreds a piece. You can also
make them yourself with an AS5202 port contour cutter from McMaster
>>
>> On Sat, Feb 6, 2021, 3:32 PM William Claybaugh
<wclaybaugh2@xxxxxxxxx <mailto:wclaybaugh2@xxxxxxxxx>> wrote:
>>>
>>> I’ve spent most of a week looking for a AN-4 cross (aluminum
or stainless) that will accept o-rings on each mating surface, so
far w/o success.
>>>
>>> Is such a part made? Anyone know where I might order several?
>>>
>>> Special bonus if one leg were an NPT male....
>>>
>>> Slow leaks are proving to be a problem in the buildup of my
pneumatic separation system; the actuated burst valve holds
pressure perfectly but the racing grade AN-4 swivel connectors are
leaking down over about 20 minutes at the swivel side.
>>>
>>> Bill