Basic box - joint jigs like this one have been around for a long time. After you finish building and adjusting the jig, learn how get the most from it. To use this jig you. With this table saw jig, perfect box joints are easy to make in any size stock. Follow these free woodworking plans to learn how to make the jig. Box joints are a cinch to make on a router table. All you need are a sharp bit and a basic plywood jig. The biggest problem in making box joints.