Many of my clients are unsure about newel caps and how they are attached to the newels. These caps are typically fitted for larger over-the-post newels. The cap has the same profile as the handrail does. The installer has to join the handrail fittings to the cap by cutting a pie shape from the cap and the corresponding “point” on the handrail fitting.
Most installers will cut the pie shape from the cap on a bandsaw and then clean up the cut with a sharp chisel. The pie cut from the newel cap is NOT a 45deg angled cut. Instead your cut is as wide as the width of the handrail and ½ as deep. So if the handrail is 2 5/8” wide your cut will be 2 5/8” wide and 1 5/16” deep as measured from the perimeter of the cap. See the drawing below.
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