Cutting PEX pipe is a fundamental skill for many DIY plumbing projects.
Whether you're repairing a leak, installing a new fixture, or building a custom
irrigation system, knowing how to properly cut PEX tubing ensures a secure,
leak-free connection. This comprehensive guide covers everything you need to
know about cutting PEX pipe efficiently and safely.
Why Proper Cutting Technique Matters
Making a clean, straight cut on your PEX pipe is critical for two main
reasons:
It creates a smooth surface for fittings to seal against
It prevents future leaks and connection failures
A jagged or angled cut can compromise the integrity of even the
best-fitting connection, leading to water damage and costly repairs down the
line.
Tools for Cutting PEX Pipe
You have several options for cutting PEX, ranging from specialized tools to
common DIY instruments.
1. PEX Pipe Cutter (Recommended)
This is a specialized scissor-like tool designed specifically for PEX
tubing. It features a sharp, hooked blade that cleanly shears the plastic
pipe.
Best for: Frequent use, cleanest and easiest cuts.
2. Ratchet PEX Cutter
A ratcheting tool that provides extra cutting power with minimal effort,
ideal for tight spaces or cutting multiple pipes quickly.
Best for: Tight spaces, high-volume projects.
3. Utility Knife
A sharp utility knife or box cutter can make a clean cut if used
carefully.
Best for: Occasional use when specialized tools aren't available.
4. Copper Pipe Cutters
Standard copper tube cutters with a sharp wheel can work on PEX, though
they may create a slight bevel on the edge.
Best for: Situations where you already have the tool available.
Step-by-Step Guide to Cutting PEX Pipe
Using a PEX Pipe Cutter
Measure and Mark: Use a tape measure and a permanent marker to indicate
exactly where you need to cut. Wrap a piece of tape around the pipe for a
straight cutting guide if needed.
Position the Tool: Open the PEX cutter and place the pipe fully into the
cutting jaw. Ensure your mark is aligned with the blade.
Make the Cut: Squeeze the handles firmly and evenly until the blade cleanly
shears through the pipe. The action should be smooth and require moderate
pressure.
Using a Utility Knife
Measure and Mark: Mark your cutting line clearly. Consider wrapping tape
around the pipe to guide your cut.
Score the Pipe: Hold the pipe steady and use the knife to make a deep score
mark around the entire circumference.
Snap the Pipe: Bend the pipe away from the score line. The PEX should snap
cleanly along the scored mark.
Clean the Edge: Use the knife to carefully trim away any rough edges or
burrs.
Pro Tips for a Perfect Cut
Always cut straight: A 90-degree angle to the pipe length is essential for
proper fitting connection.
Deburr the edges: After cutting, use a utility knife or deburring tool to
remove any small plastic fragments from the inside and outside edges of the
cut.
Support the pipe: Hold the pipe firmly on both sides of the cut to prevent
bending or distorting the shape during cutting.
Keep blades sharp: Dull blades will crush or deform PEX pipe rather than
cutting it cleanly.
Common Mistakes to Avoid
Using saws: Avoid using hacksaws or power saws, as they create rough edges
and plastic shreds that can contaminate your plumbing system.
Making angled cuts: Crooked cuts prevent proper seating of fittings and
often lead to leaks.
Rushing the process: Take your time to measure twice and cut once for the
best results.
FAQ
Can I use scissors to cut PEX pipe?
Regular scissors are not recommended as they will likely crush the pipe
rather than cut it cleanly. Always use a tool with a sharp blade designed for
cutting plastic tubing.
Do I need to sand the edges after cutting?
No, sanding is not necessary. Simply remove any visible burrs with a knife
or deburring tool.
What size PEX cutter do I need?
PEX cutters are typically sized by the maximum pipe diameter they can
handle. Ensure your tool is rated for the size of PEX you're using.
By following these simple steps and using the right tool for the job, you
can achieve professional-quality cuts on PEX piping for all your plumbing
projects. Remember that a proper cut is the foundation of a reliable, leak-free
plumbing connection that will last for years to come.
