Round part present special challenges in the workshop. How to we safely machine them on the table saw, drill press, or other machines when their is no flat side to put against the fence and table? The best solution is usually to build a simple box jig which, as the name implies, is nothing more than a simple box made out of scraps to hold the part. While the video above uses woodworking examples, box jigs are also handy to hold round or irregularly shaped metal parts for work with machines like mills and shapers.
Basic box jigs come in two types. Open ended jigs, as shown in the first part of the video, are useful with parts that have one flat face that can be screwed to one of the faces of the box. They are very especially useful for making cuts in the round part on the table saw or band saw. Closed end jigs are used with spindles and curved parts which need to be secured from the ends and are especially useful for routing or drilling operations. While simple versions like the one in the animation at the end of the video usually just use screws to secure the ends of the work, it is also possible to build in lathe-style centers and a shop-built or store-bought indexing head to hold the piece at certain precise angles. Professional indexing heads are complicated and expensive, but a simple pivoting disk of wood with holes for a pin is often adequate for one-off jobs. Many furniture makers build simple indexing box jigs to so they can route the mortises in table pedestals to attach the legs.
While they are very simple, box jigs are one of the most useful and common families of jigs in the handyman's workshop.
No comments:
Post a Comment