Three Ways to Cut Cast Iron Pipe

snap_cutter_for_cutting_cast_iron_pipe.jpg If you own an older home, chances are part of your plumbing is made from cast iron.

Cast iron pipe holds the unique distinction of being very brittle as well as very strong, making it difficult for homeowners to modify it.

While cast iron pipe is seldom installed, it is often removed and replaced as it fails.

For this reason, knowing how to cut a cast iron pipe is essential if you intend to work on your house’s plumbing.


Image courtesy Plumbing Supply


Method #1: Hacksaw

Although a homeowner can use a hacksaw to cut through a piece of cast iron pipe, this is the slowest and most difficult method available. Using a hacksaw to cut through a cast iron pipe will often require multiple blades and should be reserved when it is the only option available.


Method #2: Cold Chisel

Using a cold chisel to cut through a cast iron pipe is much more efficient than using a hacksaw, but requires considerably more skill. A ball peen hammer and cold chisel are among the most difficult hand tools to use accurately and effectively, making this a frustrating endeavor for the amateur. In addition to this hindrance, the cold chisel method for cutting cast iron pipe only works when you have access to all sides of the pipe and enough room to maneuver your chisel.

To use this method, draw a line using some chalk around the pipe where you wish to cut it. Using the cold chisel, start making small marks around the diameter of pipe along the chalk line. Because cast iron is brittle, the pipe should split after a few rotations over the same line.

Although many cast iron pipes will break cleanly using the cold chisel method, a jagged cut is also not unusual. This may not be an issue depending on your reason for cutting the pipe, but if you wish to create a smoother cut you should be able to remove any jagged pieces with an adjustable wrench and hammer.


Method #3: Snap Cutter

If you have more than a single cut to make, renting a snap cutter is well worth the cost. This is the only method that plumbers use when working with cast iron pipe. Despite its name, a snap cutter does not really cut so much as break the pipe at the designated location. Made up of a piece of roller chain and a ratchet, the chain is placed around the pipe where it exerts even pressure around the pipe. As the pressure increases the wheels embedded in the chain bite into the cast iron until it snaps.

A snap cutter almost always creates a smooth cut and is by far the quickest method to cut cast iron pipe. Often this tool can be rented at a home improvement center if you cannot justify purchasing one for a small job.




I have a lot of hands-on experience in the home construction industry, with a good deal of experience in sustainable building. I'm mostly interested in home restoration and home renovations.

More Posts

Fun From Around the Web

  • Walnut Creek Plumbing

    Method #3: Snap Cutter – Is the one that we always use, but for some of my employees, they also used the other 2 methods depending on the situation.

  • Dswhatley

    Could you use an angle grinder. If so what blade?