Thread: Basic Ball Drilling Jig

Problem: How to easily drill 37mm (and other sized) balls made from beechwood ?

Solution: Build a basic homemade jig.


Looking around my workshop I found a scrap piece of MDF 16mm thick by about 9” square. Next I marked out four equal quarters. In the centre I first drilled a 35mm socket 5mm deep with a forstner bit, then I drilled a 25mm x 5mm socket in the centre of the 35mm socket so that the ball of the size I want to drill sits comfortably. Then I turned the MDF over and I routed four 20mm wide x 8mm deep slots. Next I through routed four 10mm slots down the centre of the 20mm slots. These slots will take 10mm bolts later on. Then I found a couple of scraps of timber about 2” wide x 20mm deep and drilled a 35mm hole through both pieces. I cut the pieces into four lengths and trimmed the ends so that all four pieces, when positioned, would fit against the ball. Using double sided tape I positioned the four pieces of timber around the ball and turned the jig over so that I could mark out where to drill the holes in the timber pieces that would take the four 10mm bolts. After drilling two holes in each of the timber pieces, two holes to allow for greater adjustment, I placed 10mm bolts through the base of the jig with the heads of the bolt resting inside the routed slots. Each of the timber pieces are held in place by a 10mm bolt and wing-nut and are pushed up against the ball to hold it securely for drilling. I tried it out and I drilled a hole without any movement of the ball and that’s that! Crude but functional