Copper Drain Stub Out?

[JaCkaL829]

Hello,
Quite some time since I've posted on here, but I've always appreciated and respected all of the member's feedback anytime I've come into a problem, or wanted to look something up plumbing related. Although I'm by no means a plumber, I still enjoy the work, and find it really fascinating work.

Anyway, my good friend of mine is doing a 'soft renovation' of a powder room off her kitchen. Just a simple cosmetic reno without really breaking anything. She would like to install a new toilet and pedestal sink. Upon disconnecting and removing the old toilet and sink (just a basin held to the wall with a large metal clip?) I noticed that her stub out for the drain of the sink is made of copper, 1.5" I'm sure. It appears it has a male threaded ring soldered to the end. Her P-trap was an older silver plated brass one that screwed directly into the male ring. I'm just wondering what is the best/simplest way to hook up her new sink? I'm not confident that the new sink drain length will be the same as the old one. I'm thinking if I have to extend the stub out, I can put a PVC FIP Hub adapter right into the copper, than a small length of PVC, followed by a 1.5"-1.25" trap adapter, than just put a 1.25" trap the rest of the way. Would this be correct? I'm looking to do this the most cost efficient way (hence PVC), but more importantly I want to avoid any issues in the future.

At this time I don't plan on breaking the wall more to try to remove the copper stub out, and I don't like the idea of the Fenco no hub couplings since it will be visible; but like I said I'm open to suggestions as to make it correct.

If it we're my home, I would probably break up the wall and cut the steel drain, and just tie in a new PVC san tee, and PVC the whole drain, but she has limited time, and money.

Btw the drain was working correctly/fine no leaks or drips. I just figured this would be a good time to replace since there was a good amount of corrosion/build up in the trap.

Thanks!

 

[OLD TIMER]

Look at he height requirements for the drain outlet in the instructions that come with the new sink. if the height of the drain outlet is ok
then I would leave it alone unless you want to do major work. trap adapters are normally close to the wall. being that its 1-1/2" it should be in
good shape for a lav.

 

[Sponsor]

 

[Reach4]

I can put a PVC FIP Hub adapter right into the copper,

I doubt that existing copper matches a FIP thread. I suspect that is a trap adapter. You might be able to put a plastic nut made to go onto a trap adapter there.

I may be incorrect in this. I am not a plumber.

I did not know that pedestal sink and easy could be used in the same sentence.

 

[JaCkaL829]

I doubt that existing copper matches a FIP thread. I suspect that is a trap adapter. You might be able to put a plastic nut made to go onto a trap adapter there.

I may be incorrect in this. I am not a plumber.

I did not know that pedestal sink and easy could be used in the same sentence.

I took the brass trap home with me. Last night I went to the box store to make some returns and ended up buying the 1.5” male and female adapter (just to see how they fit). The old brass trap screwed into the new male adapter, so wouldn’t the female adapter screw into the existing copper stub out?

I’m hoping this isn’t too difficult of a job regarding the pedestal sink. I know space is a lot more limited compared to a trad vanity. I did uninstall and reinstall my older pedestal sink when I bought house to renovate it, and it wasn’t the easiest but doable.

 

[OLD TIMER]

Wait, I'm lost.

 

[Reach4]

I took the brass trap home with me. Last night I went to the box store to make some returns and ended up buying the 1.5” male and female adapter (just to see how they fit). The old brass trap screwed into the new male adapter, so wouldn’t the female adapter screw into the existing copper stub out?

If it fits, then good, no matter what you call it.

I think you are talking about putting the plastic nut from a plastic trap adapter onto the existing copper male thread. I don't think you are talking about screwing a whole trap adapter onto what you have.

 

[Terry]

If you have 1.5" on the stubout, I just use a 1.5" trap and reduce for the tailpiece.

 

[JaCkaL829]

I attached a couple more pics to describe what I did above as to not confuse anyone. The original 1.5" silver plated trap is the first one. From what I read this has different names such as "LA" I guess because it has the cleanout port on the bottom of the trap since you are not going to unscrew it from the copper stub out every time to clean it. The other pics are of the male and female adapter, one to show the threading is the same as the brass adapter soldered onto the copper stubout, and the second to show the female adapter going into the male (although I won't be using the male PVC adapter at all). Looking at Terry's photo I guess I just need to get a 1.5" trap that has the trap arm with the slip nut to connect to the last curve of the trap. Once I measure I cut the trap arm and glue it to the PVC adapter?

I also forgot to ask, but should I put dope and/or Teflon tape on the threads of the brass male adapter for the female PVC adapter? Dope seems more appropriate than tape, but I never know when to use the Teflon and I feel it's used too often when it shouldn't be.

Thank you all for your responses, I do appreciate it.

 

[JaCkaL829]

I attached a couple more pics to describe what I did above as to not confuse anyone. The original 1.5" silver plated trap is the first one. From what I read this has different names such as "LA" I guess because it has the cleanout port on the bottom of the trap since you are not going to unscrew it from the copper stub out every time to clean it. The other pics are of the male and female adapter, one to show the threading is the same as the brass adapter soldered onto the copper stubout, and the second to show the female adapter going into the male (although I won't be using the male pvc adapter at all). Looking at Terry's photo I guess I just need to get a 1.5" trap that has the trap arm with the slip nut to connect to the last curve of the trap. Once I measure I cut the trap arm and glue it to the pvc adapter?

I also forgot to ask, but should I put dope and/or Teflon tape on the threads of the brass male adapter for the female pvc adapter? Dope seems more appropriate than tape, but I never know when to use the Teflon and I feel it's used too often when it shouldn't be.

Thank you all for your responses, I do appreciate it.

 

[JaCkaL829]

I just though about it again, I don't think I can glue the trap arm, so I "believe" I would need to use a p-trap that is hub - hub and just glue a piece of 1.5" pvc to the fip adapter on one side and to the trap from the other side. Than as Terry said, glue a trap adapter for the tailpiece going down into the trap.

 

[Reach4]

I now agree that you bought fittings that are regular NPT.

I was mistaken on earlier comments. The thread on 1-1/2 NPT and the trap adapter nuts seem to both be 11.5 tpi.

I think a trap adapter nut will screw onto the copper directly.

I am thinking that you could buy a 1-1/2 in. PVC Threaded Trap Adapter with Nut and Washer. I think you could screw that onto your copper, or, better yet, you could discard the big piece and use the nut and washer directly on the copper.

 

[OLD TIMER]

An 1-1/2" trap arm should slide in that adapter coming out the wall, if it does, use the compression ring and slip nut that comes
with a new 1-1/2" trap. if it doesn't, than buy an 1-1/4 trap and use a 1-1/2" x 1-1/4" reducing compression ring that comes with
a 1-1/4" trap. sometimes you have to take a wire brush to the inside of a used drain and clean it out for the trap arm to fit.
NO GLUE, NO TAPE, NO NEW TRAP ADAPTER. A LITTLE DOPE ON THE TRAP THREADS IS OK.
I'm reiterating what Reach4 is telling you.

 

[JaCkaL829]

Thank you reach 4 and old timer. After reading what you said, I think I found what I need: a 1/2” to 1/4” slip joint reducer. It’s just the zinc nut and washer. I’m going to do the whole trap in 1.25” for space saving. Looks like the trap arm will fit in the brass stub out and getting sealed by the washer and zinc nut to hold it.

Now the question is how far do I stick the trap arm in the brass stub out?

 

[Reach4]

Now the question is how far do I stick the trap arm in the brass stub out?

Not so far that it reaches where the pipe starts to go down vertical. Give it some margin. I am guessing maybe 2.5 inches if you are cutting the tailpiece trap arm to length. If the trap arm does not need cutting, I am thinking 1/2 inch or more would be enough.

 

[OLD TIMER]

Its called a trap arm. insert at the very least 1-1/2"