gluing THREADED PVC fittings?
 

i have a few threaded fittings that i know for sure i won't be taking apart. If i glue them together with PVC cement, will i get a good seal?

You will get just as good a seal if you use a little teflon tape.

I believe it is not recommended. I'm not sure you will get a better seal than tape. When you glue the threads, screw it on, the screwing action doesnt allow even coverage of the glue. Air bubbles form in the threads.

I would not glue a threaded fitting. The cleaner and the glue actually melt the plastic it is not like using silicone which is added to the item. So adding the cleaner then the glue will actually melt away the threads and can hurt the seal. If it is threaded the use teflon tape, if no threads then glue.....

Use PTFE tape or paste. As mentioned, solvent cement will not fill the voids in the threads and may pose a problem down the road. The cement has very little filler in it.

so we're 3 for 1... Looks like i shouldn't do it. How much teflon tape do i use? And is Thread seal tape, the kind you get by the air tools in walmart the same as Teflon tape?

Yes, most likely the same thing. It is usually on a little blue spool and it is white in color. Same thing that i use for regular plumbing in the house and also my air tools. There is also yello teflon tape, but that is for gas pipes. But it is actually the same material it is just thicker.

But if it is white and on a blue spool that is the ticket. I would go around the fitting about 2-3 times. Most PVC threaded connections will seal even without the teflon because teh threads are tapered. So the teflon just makes sure that the seal is nice and tight in teh threads...

LOL when i read this i thought...ohh man someone else made my mistake too...i was actually redoing some plumbing and had to cut the pipe directly above my return pump..i cut it glued on the union and then threaded the piece back onto my pump...i guess i was sloppy with the glue and it ran down the inside of the pipe and glued to my pump...what a real PITA...

anyway use the teflon tape...i use the orange stuff...but the white is perfectly fine...2-3 wraps MAXIMUM...and wrap the tape in such a way that when you thread the parts together you actually tighten on the tape instead of peeling it back onto itself..

hold piece in right hand, threads to the left....put the tape on the side of the pipe closest to your thumb and hanging down...wrap around the pipe under and over, [clockwise if you look at the threads from the end]...

3 -4 full wraps around the threads in a clockwise direction will do just fine.

Start with 2-3 wraps... using too much tape does not help and puts a lot of stress on the female fitting.

I very seldom use teflon tape for threaded PVC or for threaded pump connections. Silicone or pipe dope is much better.

I generally use silicone. Just a smallish bead around the top inside lip of the female part and thread in where comfortable and it will seal perfectly every time. Its removable, will never leak and especially for threading tapered fittings into bulkheads, or more importantly pump volutes, when using silicone you do not need to thread the fitting in all that far to make a perfect seal so your tapered fitting wont potentially stress and break the volute.

twice, clockwise with teflon will be plenty. Don't over tighten or you may crack your fittings, also more likely to happen with more wraps/layers of teflon.