How to Accurately Drill a Ball Through Its Center
by nunopcardoso in Workshop > Tools
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How to Accurately Drill a Ball Through Its Center

My goal with this instructible is to present an easy jig to drill balls through their centers.
This jig can be built in 5 minutes.
To build this jig we need the following materials:
- Fiberboard
- 2x drywall screws
and the following tools:
- Drill press
- Screw driver
- Hole saw (https://en.wikipedia.org/wiki/Hole_saw)
- Table saw (or, alternatively, anything that is able to cut through fiberboard)
Prepare the Base








In this step I made 2 squares out of scrap fiberboard.
My squares were 12x12cm.
Drill the Base





In this step, I joined the two pieces by using drywall screws.
Then, I drilled the top piece through its center using a hole saw. Since the hole saw has a pilot drill bit, the bottom piece is left with a hole, serving as an alignment mark to the top piece's center.
Drill the Balls



To drill a ball, align the jig with the drill press. Ideally, the jig should be clamped in place after it is aligned. Alternatively, add rubber feet to the jig to prevent it from spinning/moving.
Place the ball on top and you are good to go!