Cannot thread plastic nut onto galvanized/iron pipe

[chuckd83]

I installed a disposal over the weekend. Pretty straight forward project until I got to the (galvanized, iron?) sewer line coming out of the wall. It is threaded and thought the plastic nut would go straight on.

I don't know if it's the corroded threads or what, but I cannot get the plastic piece on. Maybe the wrong thread pitch? I've attached a picture. Any way around this other than keep trying?

 

[hj]

The threads are corroded, but the nut does NOT screw on to it anyway. You need a threaded brass "trap connector" on the pipe THEN the trap into it with a slip nut.

 

[Sponsor]

 

[chuckd83]

The threads are corroded, but the nut does NOT screw on to it anyway. You need a threaded brass "trap connector" on the pipe THEN the trap into it with a slip nut.

Thank you very much for the reply. It didn't seem correct to connect the plastic directly to the galvanized pipe.

Is this the product you mean?
https://www.ferguson.com/product/br...1-12-in-fip-waste-connector-b197cx/_/R-990426

 

[Reach4]

That is what hj means. You will need to clean those galvanized threads enough to get the pipe adapter into place. Maybe steel or brass brush and some PB Blaster, and lots of time. Maybe a dental pick too.

You would also probably be enlarging the wallboard hole.

 

[Terry]

I sometimes need to replace the galvanized nipple from the wall on kitchens. The threading tends to disappear over time.

 

[Jadnashua]

It almost looks like that may be a 'close nipple'...IOW, it's all threaded, and directly fits into a threaded socket behind it. IF that's true, it might be good to consider replacing it with a brass one that won't corrode. Now, getting it loose could be a pain. IMHO, any time you can replace old galvanized piping when doing some renovation, then is the time to do it. It never was a good idea, just a less expensive option.

 

[Dj2]

1. First you have to open a bigger hole.
2. Most likely, the nipple is fused to the T in the wall.
3. I'd cut the vertical pipe in the wall below the T and above the T, with enough space to install #5.
4. Then clean the cuts.
5. Using 2 no hub coupling shielded connectors, install a PVC or ABS T with a drain arm to the trap.
6. The arm can be rotated at the coupling to where you will need it.
7. Tighten the couplings.
8. Finish the hole in the wall.

 

[chuckd83]

I got the threaded brass trap connector and it won't thread on. The initial nipple threads are damaged so I can't even get it started. The rest of the threads are fine. If I can somehow get it past the first thread, it would be fine.

I've tried PB blasting and scrubbing it, but doesn't work. Any other thoughts?

Can I use some sort of fernco adapter on this? I assume not since it won't make a seal against the threads.

 

[Jadnashua]

A triangular file might help you clean up the threads on the nipple. If you can exchange it, I'd get one that wasn't damaged! A die could clean up the threads, but that probably would be an expensive option for a one-time use. A triangular file is more likely to be useful again down the line.

 

[Jadziedzic]

Search for "thread file" online or check your local hardware store; cleans up/restores threads faster than a regular file.

 

[Double J]

Hi Guys,

I have a similar problem. I am trying to cap a galvanized steel pipe tee to stop a leak. Unfortunately, a pipe was cut off and ruined the threads on the tee. I cannot thread the cap on it. Can you please help how to resolve this matter?

1. Can the threaded piece be taken out of the tee and then capped with some piece?
2. Should I repair the thread and then attach the 1 1/2 inch galvanized cap?

Please let me know the easiest solution to this and what tools/parts I will need?

Please see link for pictures and video of the problem at hand.

Plumbing

14 new items · Album by J

photos.app.goo.gl

Thanks in advance for all your help!