Editor’s note: Our Mind Upon Mind series is a nod to a 1937 Chips from the Chisel column (also featured in “Honest Labour: The Charles H. Hayward Years”), in which Hayward wrote, “The influence of mind upon mind is extraordinary.” The idea being there’s often room for improvement. (You can read the entire Chips from the Chisel column here.)
And so we ask for submissions: After building projects from our books, what else have you thought of, tried out and improved upon?
Today’s submission is from Jay Abramovitz in Voorhees, New Jersey.
I came up with an approach for accurately drilling holes at compound angles that has worked surprisingly well for me.
I started with three 2′ narrow lengths of pine. I glued two pieces together to form the “foot” of the jig. I attached the third piece (the “arm”) to the foot by drilling a hole through both pieces. I used a machine screw with a wing nut, which allowed the arm to rotate. I then attached two long eye screws to the opposite end of the arm a few inches apart to form a “gun sight” of sorts.
By placing the foot on my workpiece, I was able to line up the straight edge of the foot with my sightline.
I rotated the arm to the resultant angle needed (measured with a protractor) then moved the jig forward or back along the sightline on the workpiece until the location for the hole on the workpiece (the “bullseye” if you will) could be sighted through the two holes of the eye screws.
I then secured the foot to my workpiece with a clamp to make sure it didn’t move.
I placed a piece of tape on the back of my drill and used a Sharpie to mark a large dot on the tape in line with the long axis of the drill bit.
I then positioned my drill bit on the location for the hole on the workpiece and positioned the drill so that the dot on the back could be sighted through the two holes of the eye screws. I kept the dot on the back of the drill lined up with the center of the two holes on the eye screws as I drilled (like viewing a target through a gun sight, if you will). I then knew I was drilling dead on my sightline.
Did you change up one of our projects or do you have a clever idea for an improvement? Email kara@lostartpress.com. You can read more about the submission process here.
— Kara Gebhart Uhl
Nice one! I wonder if increasing the sight radius by moving the front sight down would make things more accurate, or just harder to use.
That’s a pretty brilliant idea. The only potential downside would be marking the dot on the drill, but even that’s not hard. Thanks for the tip!
That’s some fine thinking. Well done.
Impressive in its simplicity, thank you for sharing this.
Great idea and execution! I’ll be making one of these. Thanks to LAP for this series of great ideas from some very sharp minds.
I’m having a difficult time visualizing how this works. It would be nice if you made a short video clip on this.
Here’s the quick doodle I made when I was processing how this system would work: https://cocreators.ca/sightlines_doodle.jpg
Think of it as a game where you have to align five dots: one dot is you sight, two dots are the two eye screws, the back of the drill and the tip of the drill bit are the final two. The tip of the drill bit goes into the point to be drilled on the seat. Next, the red dot you marked on the back of the drill has to be sighted through the two eye screws. If you only used one eye screw, then you could look at the dot on the drill from all sorts of angles. That wouldn’t be right! By having the two eye screws on the same plane, you make sure you are holding the drill parallel to the angle on the giant sliding bevel made from two 2-foot boards.
Your illustration is terrific, Karina. Much clearer than anything I would have come up with. Thank you!
Thanks for sharing your clever method for drilling compound angles, Jay. 😀 I’m going to try this for the leg mortises on my ‘Build a Chair from BS’ build.
If you move the eyeholes down you could line it up, and slide the bit with a bit extender through the eyeholes, insert the bit and extender into the drill, and drill it keeping the drill bit in the middle of the eyeholes. I love this idea, thanks for sharing!