Turntable w/ Adjustable brakes

"Place a straight edge across the corners of the baseplate, and make a mark with a pencil near the center of the board.   Do the same to the opposite corners.   The intersection of the pencil marks will give you a X, and the exact center of the board. Draw two lines at right angles to each other and going through the center of the X and extending six inches either side of the center.

  With a compass, draw a circle 6 5/16", using the intersection of the X as a location.   This corresponds to the hole in the bearing.   Position the bearing over the drawn circle and turn it so that the four holes in the lower bearing plate are centered over the four lines you drew before.   

Now clamp the bearing in place and drill four holes, 5/32" diameter through the baseplate, using the bearing as a template (before drilling, make sure you are using the correct holes by placing a ruler to measure the spacing of the holes, which are 8 1/2" from center to center).   

You can substitute wood screws to secure the bearing to the baseplate, and in that case, do not drill the 5/32" holes, and use a suitable pilot drill for the wood screws that you selected.   The corners of the baseplate can be rounded off for safety as well as appearance."

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