Saws

Miter saw blade is not square to the fence

When the blade itself leans relative to the fence even at the 0-degree bevel stop, joints won't close properly no matter how careful the cut is. This is a bevel calibration issue, not a blade problem.

Difficulty
Moderate
Time
20–30 minutes
DIY cost
$0–$15
Pro cost
$50–$100

Symptoms

  • 90-degree cuts leave a visible gap when two pieces meet
  • Bevel scale reads zero but cut isn't square
  • Problem is consistent across different blades
  • Cut face looks slightly angled, not straight

Likely causes

  • CommonBevel stop out of factory calibrationThe 0-degree bevel detent can shift out of true over time.
  • PossibleFence not perpendicular to the table surfaceIf the fence itself leans, the blade will never square to it.
  • PossibleDebris under the fence or table lifting it slightlySawdust buildup can tilt the fence a fraction of a degree.
  • Less commonBent blade giving a false readingA warped blade can look square but cut slightly off.

What to do

  1. Unplug the saw before making any adjustments.
  2. Place a square flat against the table and up against the blade body (not the teeth) at the 0-degree bevel position.
  3. If there's a gap, loosen the bevel lock and adjust the calibration screw or stop bolt per the manual until the blade reads true square.
  4. Clean any sawdust from under the fence and table surfaces that could be causing a slight tilt.
  5. Recheck the fence itself for square against the table using the same square.
  6. Make a test cut in scrap and check the joint fit before moving to your project material.

Tools and parts

  • Miter saw
  • Engineer's square
  • Screwdriver or hex key for calibration screws

When to call a pro

If the bevel won't hold calibration after adjustment, a repair shop can check for worn detents or a bent arm assembly.

Safety

Generally low risk

Generally low risk for a careful person. Stop if anything looks different from what this guide describes.

Related guides

Operator provides AI-generated troubleshooting information. It can be wrong. For safety-critical, electrical, gas, structural, medical, automotive safety, or other high-risk problems, consult a qualified professional.