Calling all plumbing experts...

[samnaz]

I'm dry fitting hard PVC pipe and fitting and have noticed the pipe doesn't fit fully into the fittings (I know it's not supposed to) but some aren't even close to the notch. How much give does the glue allow?

I need to know before I glue anything. My setup requires precise alignment. If the glue doesn't allow them to slide fully to the notch, can/should I hammer them all the way in? Below are some pipe/fittings I'm unsure about...

 

[Caravanshaka]

I wouldn’t hammer anything in, as you may stress the pvc enough to crack it. It looks like you are mixing schedule 80 and 40 parts, which is not a big deal, but you sometimes run into the problem described. I would suggest lightly sanding the male side of the joint until it fits dry before gluing.

 

[theMeat]

Measure into the fitting/shoulder. That’s how far it will slide in when cemented

 

[reefproaquatics]

Primer should soften the pipe enough for the fittings to slip together and the glue will lubricate the pipe. Just hold the fittings together for a bit as they may try to back out

 

[zeroc0o0l]

Good advice on holding the fitting while the glue sets, it will back out. I also marked the pvc with a sharpie for funky angles and fitting depth.

 

[samnaz]

Thanks everyone. I will try lighting sanding the outer pipe (more than I already have) so it fits in further, I will also do a practice run or two gluing pipe into fitting just to see how much it gives. This is my first time plumbing a tank (obviously).

 

[redfishbluefish]

Don't sand anything. The cleaner and cement will let the pipe simply glide into the fitting. I'd suggest cleaning and cementing both fitting and pipe. Put the pipe into the fitting and turn a quarter turn. Hold for about ten seconds.

 

[samnaz]

Don't sand anything. The cleaner and cement will let the pipe simply glide into the fitting. I'd suggest cleaning and cementing both fitting and pipe. Put the pipe into the fitting and turn a quarter turn. Hold for about ten seconds.

Is rubbing alcohol the best way to clean the pipe beforehand?

 

[smiley28]

1inch

 

[Swoody]

Is rubbing alcohol the best way to clean the pipe beforehand?

Give it a light scrub with some 180-200 grit and a little rubbing alcohol be fine.... Myself I just gave it a light sanding, got rid of any rough or loose edges, wiped it off with a rag , and off to the races..... I’ve never had a problem

 

[mikes686]

Just like redfishbluefish said, don't sand it. It's designed for a tight fit when primed and glued, it'll soften enough to slip together. It hardens and maintains a watertight seal. If you sand the fittings, it may fail.

 

[JoshH]

Don't sand anything. The cleaner and cement will let the pipe simply glide into the fitting. I'd suggest cleaning and cementing both fitting and pipe. Put the pipe into the fitting and turn a quarter turn. Hold for about ten seconds.

+1 On this :) I do sand Pipe that I have cut with 220 sand paper on the edge of the cut, just to get any burrs off the edge and provide a smooth surface to slide together. But fitting to fitting, not required.

 

[don_chuwish]

I had the same frustration when dry fitting. Hard to get everything prepped & perfect when you can't even get them fully slid together. But yeah, once they've been primed & slimed with glue they'll go all the way in.

 

[theMeat]

Don’t sand it.
Don’t use primer or cleaner and then try a dry fit.
Let primer or pvc cleaner dry before cementing.
Cement dries within seconds. Apply to both sides, male/female, slide in, 1/4 turn/twist, hold for 15-20 seconds, done.

 

[red13]

Don’t sand it.
Don’t use primer or cleaner and then try a dry fit.
Let primer or pvc cleaner dry before cementing.
Cement dries within seconds. Apply to both sides, male/female, slide in, 1/4 turn/twist, hold for 15-20 seconds, done.

What Meat said, except apply primer to both sides twice, then apply glue. Two layers of primer will get the fitting nice and "gooey" and you should be able to seat them. Also make sure you use primer not just a cleaner.

 

[andyg1960]

To sum up, sand it, and dont sand it.

 

[Fin]

I usually dry fit as best I can (without hammering) and then mark the joint (both for depth andoper orientation) and mark / number the joints so they go back together exactly as they were when dry fitted. Works for me anyway. Best example I could find at the moment.

 

[redfishbluefish]

Please, NO SANDING. The cleaner/primer as well as the cement will soften the pipe/fitting allowing them to slip together very easily....all the way to the stop.

If you haven't purchased the cement yet, the cleaner/primer and cement come as a kit.

Note that this primer is purple, which is required when used in "coded" applications. If you don't wish to see this purple, you still can purchase clear primer.

So to summarize, clean/prime both fitting and pipe. That is, take the little applicator that's attached to the top of the can and brush/apply all the way around the pipe/fitting. Apply cement in a similar manner with that brush in the top of the can.... to both fitting and pipe and slip together until the pipe stops, and now give it a quarter twist and hold for 10-15 seconds until it sets. Done! You're now a plumbing expert! :D

 

[mfinn]

Don't sand it.

 

[theMeat]

What Meat said, except apply primer to both sides twice, then apply glue. Two layers of primer will get the fitting nice and "gooey" and you should be able to seat them. Also make sure you use primer not just a cleaner.

One pass with primer is enough. Especially with schedule 80 which gets real gooey fast. Which is why I recommend cleaner instead. Too gooey/ not dry enough and it weakens the cement bond. Cleaner is more than enough and the finished product looks better.