Marco, there is no right or wrong sizes for the cams. The cams should be a bit shorter than the material you are working with. Most people use wood screws to attach the cams, I would suggest square drive screws. (Robertson for our Canadian members) Keep in mind there is no one size of cam board that will handle all jobs. You will often need to build a new box to fit your project. The cams are for holding in position, not holding down. Ski jigs are usually wider than the cam board so you can rout with out interference.
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