Very common problem and how I fix it.
Started a new thread so I can find it easier.
How to remove a copper DWV trap arm
The original poster of this link thread had a steel nipple trap arm.
When those go bad and the nipple is pretty much gone/rotten
( when the nipple has broken off from the cast santee )
It's almost impossible to cut out and re-tap the threads in the fitting.
I've have gotten lucky once in awhile.
The copper trap arms are often installed with a brass solder ring which are only 2 or 3 threads deep leaving the remaining threads inside the fitting exposed. These have to be chipped out to get the tap in to clean up the threads. be carefule the cast iron can be fragile and you can strip out the treads you still have. one time the side of the tapped fitting cracked and just fell off.Time to open the wall and cut the entire tee out.
Now you can either screw in a new plastic male adapter, brass nipple or a brass dysanco fitting if you want to install a chrome p-trap
Started a new thread so I can find it easier.
How to remove a copper DWV trap arm
The original poster of this link thread had a steel nipple trap arm.
When those go bad and the nipple is pretty much gone/rotten
( when the nipple has broken off from the cast santee )
It's almost impossible to cut out and re-tap the threads in the fitting.
I've have gotten lucky once in awhile.
The copper trap arms are often installed with a brass solder ring which are only 2 or 3 threads deep leaving the remaining threads inside the fitting exposed. These have to be chipped out to get the tap in to clean up the threads. be carefule the cast iron can be fragile and you can strip out the treads you still have. one time the side of the tapped fitting cracked and just fell off.Time to open the wall and cut the entire tee out.
Now you can either screw in a new plastic male adapter, brass nipple or a brass dysanco fitting if you want to install a chrome p-trap
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