I have an aluminum AN832-3D (bulkhead union, two male 3/8-24 UNF w/ 37° flares). I need to connect it to a brass male 1/8 NPT fitting and can't seem to find a female/female fitting-coupling that will do the trick.

If it is not aircraft use you could try these people.http://pitstopusa.com/c-132179-fittings-hoses-pipe-thread-to-an-adapters.html. or if it is an aircraft part http://www.aircraftspruce.com/search/search.php
You may have to use a larger pipe thead and an adaptor to get down to the size you need.
B.E.

 

The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them.  Old professor

I checked aircraft spruce they don't appear to have what i need. The existing connections are both male so I  need to find a double female fitting.  

Check this link
http://pitstopusa.com/c-132871-fittings-hoses-pipe-thread-to-an-adapters-male-pipe-thread-to-female-an.html

You may have to use a short pipe coupler to complete the NPT connection.

The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them.  Old professor

iongno--you should be aware that coupling brass to aluminum is never a good plan because of the potential for galvanic corrosion.

You might try googling "Autoclave Engineering".

I agree with the caveat about galvanic corrosion. Are there aluminum connections on the other side of the bulkhead union? Any chance of changing the bulkhead fitting to a more compatible metal?

Berkshire - Earl's Ano Tuff may do the trick. Ideally I would like to have just one part to make the connection. This part would be great, http://www.holley.com/17982NOS.asp, if only it was an AN-3 and at $37 is more than I would like to spend.

swall - I agree corrosion is a concern. However the BH fitting attaches to an aluminum channel. The BH fitting is a lot cheaper and easier to replace than the Al channel. The treads will have ARP thread sealer added that should help with corrosion.

The brass fitting is existing hardware for 1/8" copper tube brake lines. Replacing the lines is out of the question. The system I'm designing is a kit. I would like to keep the fittings so the end user does not need special tools to change it and can go back to original equipment.

http://www.adaptall.com/

 

Mint

I have added your link to my favorites . That is a very useful site.
And I have given you a star for it.
B.E.

The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them.  Old professor