I have a 3/4" pipe thread hole in an aluminum plate, and I need
to be able to connect to both sides of it using pipe fittings, with
the through bore size not so critical. I have been looking around the
web trying to find out what to call a double sided reducing bushing,
but so far no luck. Short of having one made, I'm wondering if anyone
has had this problem before and what you did about it. FWIW, the
fittings would hopefully be stainless, but there's no serious need for
it other than everything else in the system is.
Thanks!

"Carl M" wrote in message
...
I have a 3/4" pipe thread hole in an aluminum plate, and I need
to be able to connect to both sides of it using pipe fittings, with
the through bore size not so critical. I have been looking around the
web trying to find out what to call a double sided reducing bushing,
but so far no luck. Short of having one made, I'm wondering if anyone
has had this problem before and what you did about it. FWIW, the
fittings would hopefully be stainless, but there's no serious need for
it other than everything else in the system is.
Thanks!

Search on 'bulkhead coupling'.
http://www.kthsales.com/website/vend...n-Fittings.htm

http://www.discounthydraulichose.com...ings_s/220.htm

HTH- Carl (not the same Carl and not Karl)

On Mar 16, 11:31*am, "Carl Byrns" wrote:
"Carl M" wrote in message

...

* * I have a 3/4" pipe thread hole in an aluminum plate, and I need
to be able to connect to both sides of it using pipe fittings, with
the through bore size not so critical. *I have been looking around the
web trying to find out what to call a double sided reducing bushing,
but so far no luck. *Short of having one made, I'm wondering if anyone
has had this problem before and what you did about it. *FWIW, the
fittings would hopefully be stainless, but there's no serious need for
it other than everything else in the system is.
* * Thanks!

Search on 'bulkhead coupling'.http://www.kthsales.com/website/vend...n-Fittings.htm

http://www.discounthydraulichose.com...ings_s/220.htm

HTH- Carl (not the same Carl and not Karl)

I've seen those, but not quite what I need. I have atmospheric
pressure on one side of the plate, high vacuum on the other, and I
need to pipe through a different pressure, so it has to fit the
existing pipe thread (the plate is too big to take back to the machine
shop, and I'd rather not drill it out for a baseplate NPT adapter,
which might be too small) and let me connect pipe fittings on either
side.
Thanks for looking, though!

On Mar 16, 12:36*pm, Don Foreman
wrote:
On Sun, 16 Mar 2008 12:22:30 -0700 (PDT), Carl M

wrote:
* * I have a 3/4" pipe thread hole in an aluminum plate, and I need
to be able to connect to both sides of it using pipe fittings, with
the through bore size not so critical. *I have been looking around the
web trying to find out what to call a double sided reducing bushing,
but so far no luck. *Short of having one made, I'm wondering if anyone
has had this problem before and what you did about it. *FWIW, the
fittings would hopefully be stainless, but there's no serious need for
it other than everything else in the system is.
* * Thanks!

I would take a 3/4 to 1/2 reducer, bore it out so a 1/2 nipple will
pass thru, silverbraze or weld the nipple in place. That gives you 1/2
NPT male threads on both sides of the plate.

Now that's a possibility. If all else fails, I'll go that route.
Good tip, thanks!

How about this: Use a nipple a few inches long, and run a pipe die up about
half way. Run a pipe tap into the hole far enough so the nipple will thread
in and come out the other side. Use plenty of sealant, since you may not
have a good taper-to-taper fit.

On Sun, 16 Mar 2008 12:22:30 -0700 (PDT), Carl M
wrote:

I have a 3/4" pipe thread hole in an aluminum plate, and I need
to be able to connect to both sides of it using pipe fittings, with
the through bore size not so critical. I have been looking around the
web trying to find out what to call a double sided reducing bushing,
but so far no luck. Short of having one made, I'm wondering if anyone
has had this problem before and what you did about it. FWIW, the
fittings would hopefully be stainless, but there's no serious need for
it other than everything else in the system is.
Thanks!

I would take a 3/4 to 1/2 reducer, bore it out so a 1/2 nipple will
pass thru, silverbraze or weld the nipple in place. That gives you 1/2
NPT male threads on both sides of the plate.

On Sun, 16 Mar 2008 12:22:30 -0700 (PDT), Carl M
wrote:

I have a 3/4" pipe thread hole in an aluminum plate, and I need
to be able to connect to both sides of it using pipe fittings, with
the through bore size not so critical. I have been looking around the
web trying to find out what to call a double sided reducing bushing,
but so far no luck. Short of having one made, I'm wondering if anyone
has had this problem before and what you did about it. FWIW, the
fittings would hopefully be stainless, but there's no serious need for
it other than everything else in the system is.
Thanks!
I use a half of a 1/4 pipe coupling, turned down to fit the bored out
inner end of a 3/4 - 1/4 reducing bushing. Silver solder the two
pieces together and you have your fitting. I made a couple of these to
adapt propane tanks for my compressor.
Gerry :-)}
London, Canada