Dado ? Shims and spacers

shims come in handy when your making box joints, you can fine tune your fit you might say, I have a jig I made and use the forrest box joint blades with a couple of shims so my box joints are perfect. The biggest thing in making box joints is making sure you keep your jig clean and your box that your cutting joints on is firmly set against your fence and spacer, with a good backer. shims are very useful for tweeking a perfect fit, they can make the cut wider because the chippers are cutting a wide cut you can use the spacer to tweek the cut, say if your using a 1/4 chipper and your 2 outside cutters and it just likes a tiny bit to fit your joint then you can add the correct amount of spacers then you have a wider cut with the perfect fit, some chippers are 1/8 5/32 1/4 with a thin or thick plate, you mix and match these until your close then shim for exact fit, once you make your jig which I have several sizes I mark the blades and shims to fit the size of joint I want to make if this makes any sense, everybody has a diff way of doing things you will get lots of info and help here on the Jocks have a good day and make lots of dust