Leaking 1/2" union -- face on a lathe?

face them off and cut an oring groove in one half.

basilisk

If it ever needs disassembly, the 'just dope' solution has flaws. Why not get out the razor knife and some oaktag or gasket material and cut yourself a gasket?

Someone did a dope-but-no-gasket replacement on my car's water pump. When it needed replacement, I found that the housing parts were glued tight and couldn't be budged. No gaskets meant that the attaching bolts were a couple of turns tighter, and went into the engine block past the fully-cut-thread length (so the bolts broke, of course, at disassembly time).

I would think it would work. What is the worst that can happen? Does not work and you have to get another union.

But it might be easier to use some valve grinding compound and lap the joint smooth.

Dan

Good one! Esp. since I got o-rings!!

I remember a flat water union with flat rubber washers. Maybe the washer is old and cracked.

Heh, no washer, which is proly the real problem, given this style of union. I'll go and see what fits, mebbe a garden hose washer will do.. I can always cut a washer from 1/8" rubber.

It doesn't take much of a leak to empty a tank overnight.

Heh, washer seems to be working! When you got a hammer, everything looks like a nail.... when an empty lathe is standing around, everything seems to need turning!

What kind of pressure?

Rubber or fiber gaskets or pipe dope may just get blown out over time. Maybe a copper gasket will hold?

Face it on a lathe and then lap the mating faces with valve lapping compound (the automotive stuff will probably do a decent job).

It's 120 psi. Fiber would proly be good, or nylon. I put in a nylon-ish washer, leaked a little, tightened'er up, rock solid now for hours at 105 psi.

I thought of copper or alum, as well. But this is good for now, no machining drama req'd. And lapping is def'ly beyond my psychological wherewithall.... :(

Most modern unions don't appear amenable at all to gasketing. Which is probably just as well. Even black pipe unions have bronze facing at the mating surface, however, for a good seal.

My old-style union was all steel, tho.

My found washer works like a charm -- 106# for days. I wouldn't do this for water plumbing, esp. where access is a problem, or eventual leaks an issue, but for clearly visible stuff, these old unions+gasket seem fine. You don't really have to muscle them together, either. Two smallish channelocks did fine.

Lots of water systems have 100 psi+ pressure. My locale has pressure regulators on the input to the house.

...

Good to know - thanks for closing the loop. Bob

Municipal? Why so high?

NYC is 60 psi, max. That extra 40 psi is a lot of extra juice for 100 psi pumps, no?

effingYonkers is mebbe 30 psi -- hmmm, lemme check... I happen to have two gauges on the laundry spigots -- guess I had nuthin to do and had extree gauges, fittings.....

HOLY SHIT -- 60 psi!! Heh, my tax dollars at work.... Cain't believe I've had these gauges installed all this time, and never read them....

Maybe it's like here, lots of hills and apartments in this town. Gotta have enough oomph to get up to the top, you know. The high- rises probably have booster pumps on the upper floors, but the smaller buildings probably don't. And if the water tower is on top of the highest hill and he's at the bottom of the deepest valley, his pressure is going to be high. A little thing called gravity is involved.

Stan

I live in the land of big hills. Some places they would be considered mountains. the hills around San Francisco are about 1500' high. I live about 40 miles from SF at an elevation of 440' and they put the storage reservoirs high up the hills around here.