Instructables

Step 2: Attach the Eye-Bolts (Part 1)

Picture of Attach the Eye-Bolts (Part 1)
Next, flip the tire over so that it's top-side up. This is where we're going to attach the eye-bolts that'll attach to the chains that will support the tire swing. Since a triangle is the most stable plane, you'll want to find three spots, equally spaced around the sidewall, for each eye-bolt. You can use all kinds of geometric formulas for determining the ideal spots. I simply picked an arbitrary spot for my first hole. I went ahead & drilled it with a drill bit just barely big enough for the shaft of the eye-bolt. I put it in a spot where the fender washer won't stick out over the curvature of the tire. Here's what that looks like: