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Stesso

Measure Corner Angle and Calculate Half Angle

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1:17
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Angles for cutting crown flat

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What happens here

Before any calculations, accurately measure the interior corner angle where the crown molding will be installed. The presenter uses a digital angle finder to measure a corner, which registers as 90.3 degrees (effectively 90 degrees). He then instructs to divide this measured corner angle by two to get the 'half angle.' For a 90-degree corner, this results in 45 degrees (90 / 2 = 45). This half angle is crucial for the subsequent trigonometric formulas.

Goal: Determine the corner angle and its half-value for calculations

Tools and materials

  • Digital Angle Finder Johnson — To accurately measure the interior corner angle
  • Dry Erase Marker Unbranded — To write calculations on the whiteboard
  • Whiteboard Unbranded — To visually demonstrate the calculation of the half angle

What they say

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to punch into your phone. Let's start with 38° spring angle crown, and the complementary angle that we're using for this formula is 52°. Measure your corner. Mine is 90. Divide that by two, and you get 45. For your miter, plug this into your phone. Arc tangent cosine 52 / tangent 45, and that gives you your 31.6 miter. And for the bevel, arc sign sign 52 * sign 45, and you get 33.8,

Auto-generated from the video audio.