These jigs were designed and made by Denis Brassard and myself. The long one is hinged and can be laid with the short section at either end tor the curves at the ends of the bridge. Not shown is a short bar which straddles the two rails, and has a vertical groove for the depth gauge of a digital caliper. The jig is precision adjustable for height , so that a perfectly even thickness along the length is possible. In practice, a string at selected points is stretched across and the gap measured with a taper gauge. and the required downbearing amount added. The bridge cap material is then run through the thickness planer. Also not shown is the bass jig, which has the two rails straight and too wide apart for the router base, so has a sliding base with a groove for a templet guide. Ted Sambell