Cast-Iron Radiator Restoration: Removing old pipe nipple to make way for new fittings

HeatingHelp

Bob "Hot Rod" Rohr of Caleffi shows how to remove an old pipe nipple to make way for new fittings when restoring a radiator.

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claude_2

Important to note if you're going to use a tap to clean the threads. The tap is tapered, therefore do not run that tap all the way through or your nipple will be loose. Yes, I did this very thing about 25 years ago on my living-room radiator and had to use a ton of Teflon tape and auto form-a-gasket to fix it. I check it every year for a leak, none yet, but boy did I feel like a total idiot after pulling that little number!

DennisSirianni

Hot Rod makes the difficult simple and easy. Thank you

Jackmartin

We have all at one time or the other cut to deep and nicked the threads. Then you see people wind 6 feet of Teflon on the nipple put enough pipe dope for an entire install and quess what it leaks! I started out in the industrial refrigeration area and we used only steel pipe and extra heavy everything, ammonia does not take any prisoners. We used a pipe sealant most of the youngsters have never heard of it is called Expando. The material comes dry in the container and looks for all the world to be cement mortar. In a way it is, you take out the amount you need mix it with water until you have a realtively stiff mix and coat the nipple with it and if you have really nasty joint put some on the internal threads too.
Now, the big secret, Expando ( read the word) expands ,big suprise. Install your fitting tighten it like you would any fitting and LEAVE IT FOR TWENTY FOUR HOURS. Expando turns to a solid mass it expands into every opening it can reach and after twenty four hours you have a joint that not only doesn't leak but it is
impervious to all substances. Now, if you run across a fitting with expando ,you cannot loosen it by force no one is that Strong. However, get out you torch heat it to 300 degrees f. you can turn it out with the correct pope wrench. Stay Well and Be Blessed, Jack

retiredguy

I can see that "hot rod" has cut out a few nipples in his professional career and thanks to the other guys that show that like the rest of us mortals we can and do make mistakes when performing this "FIX". The 1 thing that I usually did when cutting a nipple out of a radiator that you had to save was to finish cutting slots by hand with a hand saw that way when you cut through the nipple the saw blade would bind slightly to let me know when to stop sawing. A large can of EXPANDO was a necessary tool to have on hand as was anti- sieze compound.

great lesson; thanks

hot_rod

Here is another thread sealant that works well on "nicked" threads. it works similar to the Expando product in that is hardens and fills gaps nicely.
https://www.highsidechem.com/leaklock.php

EBEBRATT-Ed

I have used Expando we had a job with black pipe with some kind of process oil at 550 degrees. It is what the mfg of the equipment insisted on.

And it worked...no leaks

I have nicked some threads in my time teflon tape and true blue usually does the job on normal steam or water systems

StevieD

I used the slice and chisel method to get out a stuck nipple and nicked the threads with the sawzall. Rookie mistake! I filled the nick with JB Weld, then retapped the threads. It worked like a charm. In fact, the thread repair is almost invisible. And no leaks!

Mad Dog_2

I remember working in Columbia University Main Campus changing out steam traps mid 1990s.  I made and modified all kinds of Sawzall blades and hacksaw blades to cut and cape out 1/2" Threads..many were by hand.  Atleast Brass goes fast!   Mad Dog 🐕 

Intplm.

@hot_rod
Nice video. Now when I can't show someone how to do this I will refer them to your video. Thanks @hot_rod and heating help for sharing.

EBEBRATT-Ed

That works. Nice job.

If you really want a challenge, try picking out a CI bushing and more challenging is a cast Iron plug. The cast iron tends to chip off in small pieces and won't peal like steel.