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 Lav drain tail piece extension
Author: sum (FL)

I am hooking up a pedestal sink, and the provided drain tail piece is too short.

The is a gap of 1.5" between the end of the tail piece and the top of the p-trap inlet.

So I bought a tail piece extension, but it was too long, so I had to cut it. For some reason I was distracted and cut it too short.

By too short I mean the cut extension piece is about 3.5" long, if I insert it into the p-trap inlet and let it "bottom" out, there will only be about 1/8" of the tail piece below the nut of the extension piece. Is this too short? Should I not bottom out below and go with a 1" overlap on both ends? Or should I get a new extension and cut it so it will allow the extension and the tail piece to bottom out?

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 Re: Lav drain tail piece extension
Author: sum (FL)

Second question, the drain assembly comes with a plastic "cone" under the flange. I assume it's purpose is the same as plumber's putty.



Should I still use plumber's putty with it, or just use the plastic cone thing?



Edited 1 times.

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 Re: Lav drain tail piece extension
Author: packy (MA)

get an 1 1/4 x 4 plastic slip extension. you can't see it inside the pedestal leg. the nut will have the little wings on it for hand tightening. put the extension into the trap inlet and tighten it with channel locks. now you can slip the trap up into place and tighten the plastic slip nut by hand. it is rediculous to try to get a wrench in there..

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 Re: Lav drain tail piece extension
Author: packy (MA)

yeah, use the rubber it will be fine..
what's important is the tapered rubber washer below the sink (called a mack washer). lather it up with silicone caulk before tightening it. those are notorious for leaking and once the pedestal is in, forget about tightening a leak.

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 Re: Lav drain tail piece extension
Author: hj (AZ)

GEt a longer 1 1/4" threaded tube and cut it to the proper length. It will be cheaper than an extension and make a better connection.

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 Re: Lav drain tail piece extension
Author: PlumberLoren (CA)

Use putty for the connection in the sink but turn that rubber washer upside down and put a bit of pipe dope on it prior to installing the fiber washer, then the metal washer, then the nut. Tighten the nut pretty snug but don't over tighten it. Then you will be ready for your tail piece. I hate pedestal lavatorys. They can be a PITA to install the waste properly.

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 Re: Lav drain tail piece extension
Author: Don411 (NY)

You have enough to use that piece you cut, it doesn't have to bottom out, just split the difference and be sure each end is inserted enough so that the washers can seal.

Note that the RIGHT job would be to purchase a longer tailpiece as HJ has noted.



Edited 1 times.

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 Re: Lav drain tail piece extension
Author: sum (FL)

Packy you mean to put some silicone in the space between the bottom of the ceramic surface and the top of the inveted taper washer thingie? A nylon flat washer goes under it then the big nut to tighten.

I had a leak under in another pedestal sink before and a real pain. I think it was bad machining of the overflow holes on the sides of the drain body, the bottom of the holes were cut to almost flushed with the bottom of the sink and the plumber packed blobs of plumbers putty all around the bottom. It was a real mess to undo the putty to expose the clean edges of the nut to loosen it.

This one is a new sink so I am doing the faucet before putting the sink on the pedestal.

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 Re: Lav drain tail piece extension
Author: sum (FL)

Let me see if I can find a long tube.

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 Re: Lav drain tail piece extension
Author: sum (FL)

That was my first thought as well is to get a longer tube. However when I unscrewed that tube from the bottom of the drain assembly, I noticed the threads are very fine. I for some reason assumed it is some proprietary threaded connection by the manufacturer and a longer tube would be some special order even if one's available.

Bad assumption.

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 Supply lines
Author: sum (FL)

I measured just shy of 8" from the faucet connection to the valve.

I only see 12" and 16" supply hoses. 12" would result in two awkward bends that strain the connections. 16" I can do a loop. 8" or 9" would be perfect. Do they sell 8" supply hoses?

I could not rotate the hot and cold valves to compensate because this time I soldered on male adapters at the wall and the valves are already tightened with the connections pointing straight up.

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 Re: Lav drain tail piece extension
Author: hj (AZ)

You know what happens when you "assume", don't you? They are fine threads, but that means they are the STANDARD oned for tubing.

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 Re: Lav drain tail piece extension
Author: Don411 (NY)

FYI, you realize that the tapered washer is on backwards in the pic....the tapered side goes against the bottom of the sink, the flat side faces down then the nylon washer lets the nut slide freely against the tapered washer.

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 Re: Lav drain tail piece extension
Author: sum (FL)

Don, the taper washer I showed in the pic is the way it came. It goes on top side of the sink so putty is not necessary.

There is another set which I had to remove (an inverted taper washer, a nylon washer, and the metal nut) that goes on the underside of the sink, I removed it so I can slide the top over the sink.

Hence my original question was whether that white taper shown in the pic will sufficiently do the job of the putty or should I toss it and use the tried and true putty instead. I have decided to keep this white rubber washer and see if it works as designed.

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 Re: Lav drain tail piece extension
Author: Don411 (NY)

Gotcha, thanks for clarifying. I have not seen a lav drain with a rubber washer on top like that. I agree, I would use it.

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 Re: Lav drain tail piece extension
Author: hj (AZ)

It should.

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 Re: Lav drain tail piece extension
Author: sum (FL)

This is the top side with the rubber tapered white washer.



This is the underside with the black tapered washer.



I just loosened the nut so I can squeeze some silicone in there per Packy's suggestion. I hope I don't have to take it apart because I don't think that washer will come off without a razor knife cutting and slicing it apart.



...and I did buy a long tube, and made the cut, only to find out the threaded end is "out of round" and won't even thread in. :S :S :S

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