Follow these steps to perform the five-cut method:

1. Start with a Square-ish Panel: Take a stable, flat piece of plywood or MDF, roughly 12" x 12" or larger. The exact size doesn't matter, but all sides must be straight.
2. Make Four Cuts: Label the edges 1, 2, 3, and 4. Make a cut on edge 1. Rotate the panel 90 degrees counter-clockwise and place the freshly cut edge against your sled's fence. Cut edge 2. Repeat this process for edges 3 and 4.
3. Make the Fifth Cut: With the fourth cut edge against the fence, make a final, fifth cut to create a narrow offcut strip (about 1" wide). Do not move the main panel.
4. Measure the Offcut: Carefully measure the width of the offcut strip at both ends. Measurement 'A' is the end that was part of edge 1. Measurement 'D' is the end that was part of edge 4. The other measurements (B, C) are not needed for the calculation but demonstrate the process.
5. Enter Values: Input your A and D measurements into the calculator to find the error.

Example 1: A sled that still needs tuning.
Offcut measures A = 10.000″ at the first-cut end and D = 10.005″ at the fourth-cut end. The spread is 0.005″, and with a total cut length near 40″ the calculator reports about 0.0015″ of error per foot — already close, but the fence can still come a hair tighter.

Example 2: A freshly built sled way out.
If D reads 10.100″ against A of 10.000″, the 0.100″ spread points to a badly racked fence. Because the five-cut sequence doubles the true error, your real per-side deviation is roughly half the raw gap — still far too much to cut square parts.

Example 3: Calling it done.
After a few nudges you get A = 10.000 and D = 10.001. That sub-0.0005-per-foot result is well inside the excellent range, so you can stop adjusting and trust the sled for fine joinery.

• Rotating inconsistently. Every one of the four setup cuts must go the same direction around the panel. One reversal cancels the amplification and the numbers become meaningless.
• Measuring the widest point, not the same reference. Take A and D at matching spots along the strip and keep the tape square; a slanted read on a thin strip overstates the gap.
• Letting the strip flip. The offcut has to stay oriented exactly as cut. Rotate or flip it and you're measuring handling error, not sled error.
• Chasing a zero you can't reach. A perfect 0.000 is unrealistic on a saw with any play. Aim for an acceptably small per-foot figure instead of endless fiddling.

"The five-cut is the closest thing to absolute truth we have for a sled, because it needs no outside square to be perfect. I keep a dedicated strip of MDF just for this test, run it after every blade or fence change, and record the number — the trend tells me when the sled is drifting before my parts do." — Table Saw Technician

"Temperature and a loose hold-down can move the reading more than the fence can. Clamp the work the way you always will, take two runs back to back, and only trust the number if they agree. One odd result is usually you, not the saw."

• Crosscut Sled: A jig that holds a workpiece and slides in the miter slots of a table saw to make precise cross-cuts, especially at 90 degrees.
• Fence: The reference surface on a sled or saw that the workpiece is held against to ensure a straight, square cut.
• Error Amplification: The principle behind the five-cut method. Each rotation and cut multiplies the initial error, making a very small inaccuracy large enough to be measured easily.