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I could use some help figuring out how to remove the trap under my bathroom sink from the wall. It looks like all the connections from the trap are unthreaded connecting to the outlet/wall.

I've removed both the nut at the top of the p-trap and the nut at the bottom of the sink drain (probably wasn't necessary).

TIA

"Photo of a P trap under a sink, showing a horizontal waste pipe, and white plastic cement visible in the joints"

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  • Are you replacing the sink? The only situation I think is appropriate for full solvent welded joints in drains under a sink is in very hard use environments like a restaurant, school cafeteria, the concession stand at the high school football stadium, etc. youtu.be/2befOMjA3ho Aug 3 at 1:39
  • It takes an expert to solvent fuse that drain line and trap so it ends up in the right location under the tailpiece and at the right angle. The fitting recommended in isherwood's answer allows two types of adjustment, linear along the axis and rotation about the axis. In addition, the trap should have a union in it that allows the sink end to be located in an arc. These three adjustments are all necessary to get the sink end of the trap to line up with the tailpiece. This trap was not meant for this application but for underfloor for a shower or floor drain. Aug 3 at 1:44
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Cut it off.

That's all apparently built with cement-welded joints. There is no practical way to un-weld them.

I would cut the pipe immediately downstream of that coupler near the wall and cement on a male thread adapter hub (using purple primer and PVC cement). To that you can attach standard compression fittings to build up a new trap.

"A two-part compression coupler, with a 1.5 inch diameter and threads on the hub.  A nylon nut that threads on and secures the pipe."

Protect everything from purple stains. It's permanent.

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There are bits available to drill out PVC slip fittings. Have some, haven't actually used one yet. Not sure how reliable they are, especially if the end of the pipe is slanted or jagged; I would recommend caution and carefully keeping the drill straight.

If it were to start going wrong, e.g. drill motor jumps around and the bit wants to go sideways, back off and rig some sort of hard guide for the shaft. Might use a Dremel tool. And wear a mask, goggles, have a vacuum going to catch the little PVC shaving snowstorm.

I'd think that extra care and (as a brainstorm) possibly some 'filler' cement (mix clean PVC shavings with cement to build up the fitting if needed, thin layers then give it time to harden)? might be needed.

Jones Stephens Corp J44-150 Jones Stephens 1-1/2" Ram Bit Socket Saver by westlake Learn more:

https://www.amazon.com/dp/B000HE9YS8 enter image description here

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    I've done similar as a last resort. You're left with open PVC pores and a sketchy fit, which results in a sketchy new joint. I would only do this if there's absolutely no other option.
    – isherwood
    Aug 3 at 12:42
  • Too much trouble considering the time, effort, and cost of replacement parts. Good method to file away for another situation tho. Aug 6 at 21:18
  • @isherwood do you mean the "Socket Saver" bits, or building up with filler? By "similar" what specific tool(s) did you use? Aug 6 at 21:42
  • I believe I used a variety of tools to break out the pipe, then a rotary rasp to clean up the lumps. Doesn't really matter, though--you'll ever remove exactly the right amount of material and achieve a clean, smooth surface. You'll be building up or relying on the cement do do more than it should.
    – isherwood
    Aug 9 at 19:37
  • @isherwood or at least consider the application. I agree that this seems unwise for e.g. a water supply fitting inside a wall. However this seems fine for the OP's application. Sink drains are seldom subjected to significant pressure, barring some unclogging methods, the fitting is large (lots of bonding area, better leverage), and if the joint fails during unclogging then at least someone is right there and should immediately know about it. Further, I might expect better concentricity using the purpose-built tool than a rotary rasp. Aug 11 at 16:55

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