What is the most reliable practice before making a dado cut?

• A. Verify the width with a test cut and adjust as needed.
• B. Ignore test cuts and proceed.
• C. Set the fence to a rough estimate.
• D. Remove the blade and start without testing.

Answer: (A)

Verifying the actual width of the dado with a test cut on scrap material of the same thickness is the most reliable practice. The final groove size depends on the blade setup and kerf, plus any tool runout, so a test cut shows you exactly what the cut will produce and whether depth and alignment will be correct. Use that test piece to compare against the mating part, and adjust the fence, blade stack, or blade height until the piece fits snugly but without binding. This approach avoids surprises, saves material, and ensures the finished joint sits flush. Skipping test cuts or leaning on rough estimates risks a dado that is too wide or too tight, wasting time and wood.