6 inch hole saw
From Cornhole Wiki
A 6" hole saw is a great way to cut the hole on a set of Cornhole Boards.
Below are some tips for using a hole saw.
Hole Saw Tips and Tricks
- A holesaw is great, but you have to be careful because there is no room for error. If you wobble while you are drilling you will enlarge the hole. It is also crucial that you have a straight arbor and a drill chuck that does not wobble. I use a hole saw. I set the pilot bit as far out as I can. I mark the center of the hole and then drill the pilot hole. I make sure the hole saw is sitting flat on the board, lift off the wood, start drill and let it get up to speed, and slowly lower back down to the wood, I make sure the hole saw is cutting on all sides of the hole, as this means it is cutting straight. You will have blow out on the bottom of the hole if you get going too fast at the end. It is really a feel thing, so practice makes perfect. You can also experience some blow out on the top along the grain when you start, I have tried scoring the top with a razor knife with mixed results. - from bucksboards
- I use a hole saw also. I took a piece of hardwood 3/4" thick by about 8" wide by the width of the top (24") & clamped it under were the hole would be. I drill a 1/4" pilot hole first through both pieces. Then I use the hole saw. Don't drill very far into the hardwood. I have had extremely little break out on top or bottom. On the next top drill your pilot hole in just the top only. Then using the smooth end of a 1/4" bit stick it through the hole protruding from the bottom side. Now take the piece of hardwood you used earlier & place it under the top onto the 1/4" bit & then clamp the hardwood in place. Take out the bit & use the hole saw. I think the extra wood underneath helps keep the hole saw straighter & prevents break out. - from rickster
- Another good trick, that I believe I read on this forum, is to score the top layer of your plywood by running the hole saw in reverse for a few seconds. So here's what I do. I drill the pilot in forward (obviously), switch the drill to reverse and score the plywood, switch back to forward to complete the cut. - from J2K66
References: Hole Saw Tips