Cast Iron Pipe to Radiator

[tbacon]

I am redoing a bathroom and need to move the radiator, I am just a DIY'er so limited skills. The exiting piping is cast iron. My plan was to find an elbow and remove the pipe then use an adapt male 3/4" to pex. There are a number elbows in the run that is exposed now that I removed the tile floor, however, it seems very difficult to unscrew the pipe at the elbow joints, I got one joint to break free but ti was the whole elbow and I can spin it because it is tight against a joist. There is a nice long run of pipe with space around it, I thought I would just cut that and then thread it a threading tool (I have one of the harbor freight ones that has never been used). Was wondering if this is a good idea or if I should look at other options. I have attached a couple pictures of the piping!

 

[breplum]

The piping is STEEL, and the fittings are typically CAST IRON or what we call malleable.
When cutting and threading, be sure to use plenty of threading lubricant.
Back up with wrench when threading, otherwise you can break something downstream.
If you don't know what you are doing with PEX in terms of bending, support and termination, then learn everything or use metal again.

 

[tbacon]

Thanks for the insights. Sounds like there is not some steel pipe to pex clamp type adapter to avoid the threading? I just googled PEX bending thanks for that didn't even know that I needed to consider that, seems I have some research to do! Thanks again.

 

[johnjh2o]

I am redoing a bathroom and need to move the radiator, I am just a DIY'er so limited skills. The exiting piping is cast iron. My plan was to find an elbow and remove the pipe then use an adapt male 3/4" to pex. There are a number elbows in the run that is exposed now that I removed the tile floor, however, it seems very difficult to unscrew the pipe at the elbow joints, I got one joint to break free but ti was the whole elbow and I can spin it because it is tight against a joist. There is a nice long run of pipe with space around it, I thought I would just cut that and then thread it a threading tool (I have one of the harbor freight ones that has never been used). Was wondering if this is a good idea or if I should look at other options. I have attached a couple pictures of the piping!View attachment 28729

Those fittings are cast iron. Use tow hammers. One to backup the fitting the other to hit the boss of the fitting. After a few good strikes, the fitting will crack makeing easy to remove.

 

[tbacon]

Those fittings are cast iron. Use tow hammers. One to backup the fitting the other to hit the boss of the fitting. After a few good strikes, the fitting will crack makeing easy to remove.

Thanks that is definitely something I will try!

 

[tbacon]

In the end, I cut the steel pipe with an angle grinder and threaded the pipe with a $34 tool, then used 3/4" female to 1/2" PEX. I did try banging on it and some penetrating oil then a plumbers wrench with a 5 pound sledge. I am sure it would have work eventually but I was scared I was going to crack something further down the line. Really appreciated everyones advice!