After you make the cut outs cut a 9" length of the Burke tube. The easiest way to cut the tube is with a table saw but it can be done with a hand saw. The picture shows the Burke tube cut to the proper length.


Draw the outlines for the four windows in the Burke tube with the marker and cut out #2. Space them equally around the circumference of the tube. To draw the outlines, you'll need a thin black marker and cutout #2.
Place the cutout on the bottom of Burke tube. Make sure the cut-out is rightside up (the slits on the side should be on the bottom). Draw around the inside of the cutout window.

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