AN fittings - quality control

[Rupester]

I just received the two AN816 fittings I ordered from Spruce to reinstall the replacement red cube. This is the second time I've received two of them on the same order that are notably different. Coincidentally, the last time I ordered two of these (again, from A/S) the same thing happened. Anybody else notice this? Should I prefer one "style" over the other?

[agirard7a]

Terry. In a recent thread I posted regarding
piping up my red cube. A few guys tuned in and recommended
Steel fittings.

[Rupester]

Thanx, Al. It depends where it's located and whether or not it's solid piped or with flex hoses. I'm confident Al will work fine for my installation.

[DanH]

Originally Posted by Rupester

I just received the two AN816 fittings I ordered from Spruce to reinstall the replacement red cube. This is the second time I've received two of them on the same order that are notably different. Coincidentally, the last time I ordered two of these (again, from A/S) the same thing happened. Anybody else notice this? Should I prefer one "style" over the other?

You should get a genuine AN/MS spec fitting. Anything else is fraud; the staff at Aircraft Spruce should know the difference.

We had this conversation a few years ago.

[john.schwaner]

Both styles are allowable (my interpretation of note a)

AN816 drawing note a: "at the option of the manufacturer, the smaller diameter may be drilled through the fitting from end-to-end."

Not sure if I'm interpreting this note correctly.

[az_gila]

Are they both marked "AN"?

At one time there were unmarked fittings getting delivered through the aircraft channels...

[az_gila]

Originally Posted by john.schwaner

Both styles are allowable (my interpretation of note a)

AN816 drawing note a: "at the option of the manufacturer, the smaller diameter may be drilled through the fitting from end-to-end."

Not sure if I'm interpreting this note correctly.

I read it the same way...

http://www.everyspec.com/AN-SPECS/AN...-13.010280.pdf

[Rupester]

Per the Spruce catalog, the fittings are AN816 4-4D.

Referring the pics above:
The one on the left, darker in color and less shiny, has stamped marks on each of three hex sides: HK, D, and AS
The one on the right, which subjectively appears to be of higher quality, has stamped marks on two of the hex sides: RE, and AS-D

The ones I ordered a month or so ago have identical marks.

FWIW

[DanH]

Originally Posted by Rupester

The one on the left, darker in color and less shiny, has stamped marks on each of three hex sides: HK, D, and AS
The one on the right, which subjectively appears to be of higher quality, has stamped marks on two of the hex sides: RE, and AS-D

I am sincerely pleased to hear about marking. It sounds right....manufacturer ID, AS5195 standard, aluminum.

[az_gila]

Originally Posted by Bob Axsom

What is the ID of the holes on both sides of both fittings? The D means aluminum which is consistent with blue fittings. The AN816-4 has only two pipe thread sizes:

AN816-4 = 1/8" pipe
AN816-4-4 = 1/4" pipe

Bob Axsom

To be a bit more precise, from the Mil Spec -

1/8 NPT 0.188 in. diam +/-0.003

1/4 NPT 0.261 in. diam +0.004/-0.003

These should be the standard hole diameters for a pipe fitting.