Two-by-two end-drilling jig
thingiverse
Jig for drilling into the ends of two-by-twos, in two parts that should be connected with #6 flathead screws. Designed to drill 5/16" holes with 5/16" ID / 1/2" OD x 1+1/2" aluminum bushings (e.g. https://www.amazon.com/gp/product/B08434PW1C), but may be adaptable to other sizes, or for use without bushings. TwoByTwoEndJig-v1.0-standalone.scad / p1123-TwoByTwoEndJig-v1.0.stl is the part that is to be clamped to a two-by-two. DrillBitBushingJig-v1.2-standalone.scad / p1011-DrillBitBushingJig-v1.2.stl is the part that holds the bushing parallel to the board. Or at least to the sides of the end jig. Or can be bolted to something completely different, for other uses. Screw holes are countersunk in both parts, so direction is up to the user, but I recommend pointing away from the board, so that the top of the guide can be pressed as close to the end of the board as squareness of the end allows.
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