Sealing sink drains and traps?

[MushCreek]

We're getting new countertops in our kitchen, which means of course that the sinks have to be removed and re-set. When I built our house, I had nothing but trouble getting the stupid drain fittings to seal reliably. I'm not looking forward to going through that again, but here we are. I tried lots of things- buying better fittings, buying fittings at a plumbing supply house, running hot water through the drain while tightening them, etc. The only thing I found was to to make a ring of plumber's putty, put it inside the fitting, and tighten it up. I was told that that's totally hack and a pro plumber would never do that (it was a pro plumber that taught me that trick). So what's the secret? What DO pro plumbers do?

 

[Magnum440d100]

Following, as the right side of my kitchen sink leaks like a sonofa. Previous owners solution was to cover every joint with clear silicone, and put a catch can down there to collect the drips.

I only use the left side Lmao.

It’s one of those projects that I KNOW if I start, it’s gonna be a can of worms.

Good luck!

 

[jack stand]

How is it that a zero pressure sink drain can cause more grief than a pressurized supply line?
I was shown by a licensed plumber to set the drain assy in a bed of putty, tighten and clean up the "squeeze out" also.

 

[billconner]

Is this the drain to sink, or pipe joints like either side of trap?

 

[DGersic]

For the basket, set it in plumbers putty unless it comes with gaskets and directions not to.

For the drain lines, I’ve had good luck with the basic cheap plastic pipes that come with softer plastic gaskets and hand tight plastic nuts. The stuff from the local box store, nothing special. The only one I had leaking recently was because the brass nut cracked at the basket. Replaced it with a plastic nut, it’s fine now.

 

[K'ledgeBldr]

Are we talking about the sink drain/basket assembly to the sink?
Or is this more about the drain pipe/trap assembly?

 

[flat350]

Work from the basket strainer down, tighten tailpiece to basket strainer, pipe dope on both faces of the tailpiece washer not the threads, install tube from wall, don't tighten the nut, adjust wall piece to meet trap, fit u bend and tighten both nuts, tighten nut at the wall, light coating of Rectorseal or Megaloc where the compression ring sits on the fitting not the threads, hand tighten the nuts and 1/4 turn or so with channel locks.

 

[MushCreek]

I'm talking more about the trap and associated fittings. I usually have good luck with the basket to sink joint.

 

[mike93lx]

I have had great like with the heavy duty kits from keeney that use thicker plastic and rubber washers.

Tight as you can, then hot water, then tighten again. Works every time for me.

You could always go with pvc too

 

[JRC3]

I do several sink traps a month and never have problems. Hand tight isn't enough, I always give a nudge more with Channellocks. Decades ago I used to use this before I got a feel for things.

RectorSeal T Plus 2 in. 4 oz. Teflon Pipe-Thread Putty/Sealant 23633 - The Home Depot

www.homedepot.com

 

[Renegade1LI]

A common problem is overtightening, snug check for leaks snug again. Also make sure your alignment is good and there's no binding. I Like the schedule 40 two piece traps, easy to remove and clean.

 

[housewolf]

We're getting new countertops in our kitchen, which means of course that the sinks have to be removed and re-set. When I built our house, I had nothing but trouble getting the stupid drain fittings to seal reliably. I'm not looking forward to going through that again, but here we are. I tried lots of things- buying better fittings, buying fittings at a plumbing supply house, running hot water through the drain while tightening them, etc. The only thing I found was to to make a ring of plumber's putty, put it inside the fitting, and tighten it up. I was told that that's totally hack and a pro plumber would never do that (it was a pro plumber that taught me that trick). So what's the secret? What DO pro plumbers do?

Whoever told you that’s a hack, is a hack.
- “pro plumber”

The ring of putty goes between the bottom of the basket strainer and the sink. Bottom side would typica be; rubber washer against the sink, cardboard washer, then nut

 

[firebirdparts]

Goo for the win. Plumbers putty is okay, soft seals (not that nylon) also okay. RTV is best in my opinion. I'm not saying I use any of these, but they sure work if I have to. Look at the surface and you'll see where you've got a mold line interfering with the shape of the seal. You can improve that. I'm talking your p-trap kit here. Or, you could probably still buy a metal p-trap with rubber washers.

 

[MushCreek]

It's interesting; I looked up online, and every video I watched had a different technique and/or solution. Some called for hand tight only, others called for wrenches or channel locks. Some called for goo, some didn't. There certainly wasn't any consensus. I've long felt that a lot of plumbing design is very poor, and if everything isn't just right, it will leak. I went through all kinds of hell trying to get the threaded fittings to seal. Of course, most of that stuff comes out of China now, and the threads are awful.

 

[drmarkr]

A common problem is overtightening, snug check for leaks snug again. Also make sure your alignment is good and there's no binding. I Like the schedule 40 two piece traps, easy to remove and clean.

This.

The most common cause of leaks is stress in the alignment. There can't be any, at all. Snug handtight. If you see a leak, snug once more. If that doesn't stop it, loosen it and reposition the pieces and tighten again. YMMV, of course, but this is how I was taught years ago, by a plumber buddy that caught me trying to jack everything up with putty, lol.

 

[K'ledgeBldr]

The $5 trap kits that are made of plastic are/can be hit or miss. I have found that the mold joint where the flair and seat are can prevent a good seal. Instead of jackin’ with them- I plumb kitchen sinks with Sch40 pipe and fittings. The trap has union type fittings; and a little Teflon dope to the threads can help seal- but it’s more for keeping the threads from locking up.

 

[bluedog225]

2” pvc. Works 100%.

 

[billconner]

I installed two sinks in kitchen a couple of years ago. Ikea sinks with a rubber gasket - no putty like last time. Home Depot traps, etc., hand tightened. No problems.

 

[CraigStu]

I am w/ drmarkr. I buy the trap kits w/ the extra long tubes. There needs to be two of the 180deg tubes to form the trap. This way you can adjust the tubes by rotating them to accomodate nearly any distance. I put the nuts and seals where they need to be before starting. But they are the absolute last step. Slip slide those tubes up/down/around until there is no stress on them and none are running at even a tiny angle compared to the other. Then tighten the nuts. I will maybe use a channel lock very sparingly maybe. But hand tight should do the trick. I think some of the nuts will have two or three little wings cast into them which really helps w/ the hand grip.

 

[The Cobbler]

keep the connections aligned, not overtightened , proper seals installed the right way around .proper pipe measurements
really, there's not much else to it.

 

[PelicanPines]

At our apartment building we used cheap drain pipes and pipe dope and Teflon tape if things had a loose fit. Everyone has their own technique.

 

[Dagny]

If I have a day to set up I use GE silicone if not plumbers putty. Then gets what is called a high liner it eliminates 2 compression joints and hooks directly to the bottom of the crumb cups I put rectors seal no 5 on the plastic rings and a little on threads hand tighten cause my arms look like popeyes.

 

[Glemon]

I have to say when I first started working on plumbing you had the metal drain pipes and if you ever took them apart it seemed like they wanted to leak when you put them back together. For many years now I have used the cheap white plastic kits and had no trouble whatsoever as long as everything is lined up straight with no stress as has been mentioned already. I just tighten them by hand.

 

[Leaflessshadetree]

Get everything aligned. Tighten each fitting hand tight then loosen about 1/2 turn. Then keeping them all inline hand tighten them all.

 

[CraigStu]

I have to say when I first started working on plumbing you had the metal drain pipes and if you ever took them apart it seemed like they wanted to leak when you put them back together. For many years now I have used the cheap white plastic kits and had no trouble whatsoever as long as everything is lined up straight with no stress as has been mentioned already. I just tighten them by hand.

Yep I remember those days. One time I was doing a kitchen sink drain . As it came apart I quickly realized that it would never go back together right. That is when my rule for plumbing was formed. Always replace everything you take apart.

 

[dfiler2]

If you only want to do it once, use plumbers putty, that's what it's for.

 

[JRC3]

That is when my rule for plumbing was formed. Always replace everything you take apart.

And it's just cleaner. Who wants to **** with reusing a gunked up smelly trap to save $4.

I'll give you guys a little tip for draining the old sink trap. Instead of placing a container under and breaking the coupler apart, before you even start, push the water through the trap with a shop vac on blow. Do it from the top through the sink drain. Another tip, I almost always remove the doors on a sink base. A few screws is well worth the time saved with extra room. Even better when the hinges have quick releases.

 

[mike93lx]

If you only want to do it once, use plumbers putty, that's what it's for.

Never used, or needed, putty for a trap.

 

[dfiler2]

No not for the trap, for the drain, you don't use anything on the trap.

 

[Toolfool]

I stopped using plumber's putty years ago, when I had a second floor shower drain leak and had to re-do the drain and replace the entire ceiling below (in my 9 year old house). I used 100% silicone. Next time I saw my plumber, I bitched about it. He said that plumber's putty is job security, it starts to dry out and break down in 7 to 10 years ..... service calls.

 

[dfiler2]

My experience has been just the opposite, silicone fails after a couple of years, plumbers putty will last until you change out the sink.

 

[MushCreek]

In one of the sinks, we had a leak between the drain basket and the sink. It only leaked if there was water in the sink. Two odd things. One, the big nut that secures it has a small hole in it. Two, the plumber's putty I bedded it in was soft, as if the water was dissolving it. Putty shouldn't soften on contact with water, should it? What would be the point of it?

The only thing useful I was able to glean from watching videos is that the joint in the P-trap that goes to the wall pipe has to be perfectly aligned. That one joint is under water all the time, so it's the most likely place to leak. The other joints have a sft seal, which should help, although I've seen them leak, too. Sometimes the plastic parts have huge parting line ridges where they were molded. I spent my career in the injection plastic molding industry, so I understand all about those. I've also seen one where the parting lines were misaligned, like the two halves of the mold were out of alignment. Typical cheap ****.

 

[The Cobbler]

If you only want to do it once, use plumbers putty, that's what it's for.

most new fittings & fixtures don't require plumbers putty if done correctly ( nor should it be used )

 

[housewolf]

most new fittings & fixtures don't require plumbers putty if done correctly ( nor should it be used )

Want to guess how I know you’re not a plumber?

I see you aren’t in US… maybe it’s a Canadian thing

 

[housewolf]

In one of the sinks, we had a leak between the drain basket and the sink. It only leaked if there was water in the sink. Two odd things. One, the big nut that secures it has a small hole in it. Two, the plumber's putty I bedded it in was soft, as if the water was dissolving it. Putty shouldn't soften on contact with water, should it? What would be the point of it?

The only thing useful I was able to glean from watching videos is that the joint in the P-trap that goes to the wall pipe has to be perfectly aligned. That one joint is under water all the time, so it's the most likely place to leak. The other joints have a sft seal, which should help, although I've seen them leak, too. Sometimes the plastic parts have huge parting line ridges where they were molded. I spent my career in the injection plastic molding industry, so I understand all about those. I've also seen one where the parting lines were misaligned, like the two halves of the mold were out of alignment. Typical cheap ****.

Yes, the putty should be soft. If it’s not, roll it in your hands until it is. When you tighten the nut under the strainer you should squeeze almost all the putty out from under the strainer. Maybe lay the strainer in the hole beforehand and make sure it lays flat. The ”gap” the putty fills should be almost nothing. I don’t see any magic to it but that’s a joint that (almost) never leaks when done properly and is very unlikely to start leaking over time. If you‘re tempted to use silicon or something like that, somethings wrong and you’re putting a bandaid on it. Like I said above, there are two washers between the nut and the bottom of the sink, paper & rubber. The rubber goes against the sink and the paper against the nut. This is a conventional strainer I’m describing, I’m aware there are different types that clamp to the sink using different methods but the principle is the same.

It sounds like the p-trap “kits” you are talking about are the tubular size (1-1/2” or 1-1/4” OD) pvc. I don’t use those just because I wouldn’t want to be called back on any work I did. I’m retired and any work I do now is most likely done for free. I’m not anxious to do it once much less twice. Under a kitchen sink I like SCH 40 PVC trap, pipe, ftgs etc… most people use the space under the KS for storage and bang/bump the drains under it regularly that tubular PVC isn’t very bang/bump friendly. Under lavatories my preference is chrome plated brass as long as the j-bend part of the trap can connect at the wall. If there’s an offset required I like 1-1/2” SCH 40 with a reducing trap adapter at the tailpiece connection.

 

[nmk_61802]

I've noticed that they now make a push to connect P-trap system:

https://www.lowes.com/pd/Keeney-1-1-2-in-Plastic-P-trap/1000383267

 

[MushCreek]

When I say soft, I mean as in melting. It's like it was dissolving in water.

 

[housewolf]

When I say soft, I mean as in melting. It's like it was dissolving in water.

Are you sure it’s plumber’s putty? There are other types… (painters). I’ve got some old tubs of putty that are probably as old as some members here and it generally gets harder, you have to knead it a bit to get it workable. I’d replace what you have.

 

[bluedog225]

I got all my stuff gathered together to do a kitchen sink at my country place. Really happy I found all the tools, parts, etc. Drove out, got set up. Got half way through the job and looked down…painters putty. Dang it. I’ve never bought painters putty in my life, on purpose.

 

[MushCreek]

No, I'm quite sure I used plumber's putty. I don't even have any painter's putty.