Identify an air fitting

[rexcsmith]

I got a new fog buster coolant system for my milling machine. The only problem is that my Millport milling machine seems to have a different air fitting thread than I've seen before. The fog buster wants to connect with a 1/4" NPT. However, the thread on the machine's air switch is slightly smaller. The desired thread is about 1/2" OD and is from 18 to 20 threads/inch, seemingly tapered. It looks a lot like a 1/4" NPT from first glance but it's not. I've been all over the web looking for this thing and so far don't even know what it's called. Someone told me it's a 1/2" 20, but even if that's true, I can't find anything on the web. If you know about this thing, please let me know. I would need to get an adaptor from 1/4" NPT to this. thanks much, rex

[warmstrong1955]

Try here: http://www.eaton.com/ecm/groups/public/ ... 472120.pdf

NPT: .54 OD, 1/4"-18
BSP: .52 OD, 1/4"-19

Bill

[rexcsmith]

I think I finally got it. It's a 1/2" 18 UNF I found it at http://mdmetric.com/4300/Pipe%20Fitting ... apters.pdf

Found the exact part I need to convert from 1/4" NPT to 1/2" 18 UNF
They directed me to Motion Flow Control in Portland where it's on will call now.

Hope it's right. thanks, rex

[rexcsmith]

Bill, now I'm thinking that you might be right. I'll go ahead and pick up the one I found and if it doesn't fit; I'll check out the one you pointed me to. thanks much.

[rexcsmith]

You had the right one Bill. Parker was able to find it for me. I had no idea there were so many thread types. This one happened to be on a Chinese air switch. Thanks much. rex

[warmstrong1955]

Glad you figured it out!

That Aeroquip book is handy. With the book, a thread pitch gage, and a caliper, and you are off & running.
I got a 'thread identifier kit' when I attended an Aeroquip school in the 70's. Can't believe the price for 'em now.....
Mine should be worth even more......it's vintage....

http://www.amazon.com/Eaton-Aeroquip-Th ... B00C73GK48

BSP & BSPP is very common. I work with a lot of underground mining equipment, made in various countries in Europe, and it's most often what they use. Same is true on a lot of engines.
More often than not, China copies what they build....which includes the type of threads.

Bill

[BadDog]

Oh wow! That price is insane. I suppose it's not everyday you find a ID thread gauge including BSP and BPP (etc), but really?