Finger Joint Jig (13mm) v2

thingiverse

I've updated my earlier design for a 13mm finger joint jig: This new jig is designed to make 13 mm finger joints and is my second prototype. It features screw holes that are precisely sized and countersunk for 8g screws. The jig is intended for use with a 13mm straight bit and a guide bushing diameter of 17mm. Check out the photos to see how it's set up and used. This version is modular, allowing longer join surfaces to be created by connecting separate pieces together. However, due to the thickness of the print and the effect of the bushing on the router's plunge depth, this jig has limitations when it comes to the thickness of material it can handle. A 19mm cutting surface becomes approximately 8mm in my setup. I haven't tested whether the modular section produces a proper finger joint yet. To indicate where the bit cuts, I've added a piece of 3mm plywood under the jig – this could be removed to gain a few extra millimeters. The plywood shown in the photo is 7mm thick. This design was created using Freecad and printed in ABS.