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 Shower Clog/Opening Copper Cap
Author: dstrafford (MA)

Hi all

Thanks for letting me post here. We've had a slow draining shower for months now. It's gotten really bad of late.

The house was built in 1942 and still has all the original copper piping. I tried snaking from the tub, but the joint is at an odd angle. I'm able to get access to the pipes through a panel in another room. In the wall, I see there is a joint with a cap on it. The cap is copper with a square piece sticking up in the middle. Inside that square piece it looks like it is threaded. Does anyone have a sense of how I might be able to open that without cutting it open?

Any help would be so greatly appreciated.

Here is a picture of the cap.


Edited 2 times.

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 Re: Shower Clog/Opening Copper Cap
Author: m & m (MD)

That may be the top of a drum trap but the photo doesn't include enough of the body to be sure. Regardless, the cover unthreads but it may take some torque. Try some liquid penetrant first and let it soak a while before you attempt.

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 Thanks so much :thumb:
Author: dstrafford (MA)

Thanks so much for the fast reply!

Here are two other shots of the cap. Not sure if this helps inform anything!



Edited 1 times.

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 Re: Shower Clog/Opening Copper Cap
Author: packy (MA)

it is in fact a drum trap..
it may be tough to open but it should unscrew.
put a pipe wrench on the square top and tap gently with a regular hammer.
if there is water in the tub it will spill out the trap when you get it open so be careful.
once it is open, snake the outlet (top opening). the pipe that needs to be snaked is not very long.
once you get the snake wire thru, trickle a little water in the tub. the water should not rise above the bottom of the outlet opening. snake it a few times witht the water going thru to wash the clog into the big pipe it connects to..

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 Thanks for all the replies thus far. :)
Author: dstrafford (MA)

Thanks so much!

I can't get any access to the top of the drum trap as there are word planks everywhere. Would some sort of socket wrench do anything? I may be at the end of my DIY rope here. Thanks for all the replies thus far.

Edited 1 times.

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