air compressor fittings - how tight

[proboscis]

Hi all,

So I bought an air compressor and I have the various fittings (regulator, air dryer, etc.). I'm gonna use teflon tape, but I'm curious on how tight everything should be? Like hercules tight to the point of stripping threads, or just hand-tight + 1/4-1/2 turn? Thanks

 

[helterskelter]

hand tight then snug them up lightly. If they leak take them back apart and re-do the tape.

 

[The Cobbler]

overtightening can cause the fittings to distort & leak . a good snug plus a bit more with a wrench & you should be good

 

[MFolks]

Soapy water dribbled over the fittings will tell you about leaks. Bubbles will form quickly.

 

[EOC_Jason]

Yeah, no need to go crazy... Snug, but not gorilla tight...

 

[proboscis]

Thanks guys!

 

[Mohawk Dave]

I've learned to snug first. If it leaks, then a little more snug.

Back in the day I used to go gorilla off the bat....that's bad.

 

[bczygan]

http://www.engineersedge.com/hardware/pipe_thread_installation_13424.htm

 

[wjamyers]

since we're already discussing hose fittings I'd like to double check... on a 3/8" air hose the thin hex nut on the hose side of the connection is 9/16"... correct?

Also... all of my wrenches are too fat to fit on this damn nut (I crushed the end of my leaking hose getting the fittings off with a vise grip... )... what do you guys use to avoid this?

Also... do you reuse the fittings?

should I just put new fittings on my new hose? If not, how carefully do I need to clean the old teflon off the threads?

Sorry for all the noob questions and the hijack but I think these questions are relevant to this topic.

 

[rlitman]

since we're already discussing hose fittings I'd like to double check... on a 3/8" air hose the thin hex nut on the hose side of the connection is 9/16"... correct?...

Often, but not always. I've found ones that are metric too, and I'm not sure if there is a standard to these.

I use my PliersWrench on these a lot, as the first half of the jaws are thinner than standard wrenches.

 

[mlum6969]

you don't have to kill the fittings.. just snug and a little more.

 

[Mikeske]

Believe it or not, I have never used teflon tape on the fittings, I just tighten until they do not leak under pressure. If anything I use some never seize on them.

 

[alwaysFlOoReD]

Believe it or not, I have never used teflon tape on the fittings, I just tighten until they do not leak under pressure. If anything I use some never seize on them.

I was told by my FIL gasfitter that tape is used to reduce friction, not for sealing.

 

[doogdoog]

You could use tappet wrenches since they are thin and will be able to go between the joints or just grind down an old wrench.

 

[Sticky Grips]

NPT threads are tapered, which provides an interference fit. The threads are suppossed to slightly deform when tightening.

Add some tape or pipe sealer, and install just past snug. There's no reason to crank down on them.