|Project by Sawdustonmyshoulder||posted 06-29-2009 04:16 AM||7782 views||43 times favorited||11 comments|
I always wanted to a jig for making loose or slip-tenon mortises and I didn’t have $800 laying around for one, so like true a Lumberjock, I set out to make one.
I wanted a jig for production work so I tried to make the jig easy to use and incorporate features that make repeatable cuts. I didn’t want a lot of c-clamps or a multitude of tedious alignments.
After much research on Lumberjocks and YouTube, I came up with my version. I won’t say “my design” because I really didn’t design it. I found Kent Shepard’s jig on LJ (http://lumberjocks.com/projects/17529) and I really liked the way he designed the front bar to hold the stile (horizontally) but I couldn’t see how he held the rail (vertically). I also liked the way Kent’s jig held the stile without a c-clamp. I also like Kent’s design of the part that limits the length of the mortise and I have to confess, I was too lazy to incorporate this design, so I had to look elsewhere for inspiration for the “router sled”.
The basic design for the “router sled” came from a YouTube video (http://www.youtube.com/watch?v=Q4r6L4b2PE8). The only change I made to this design was to have my rail fixed and make adjustments from the top side of the sled with slots and knobs.
I guess the only things I can claim as mine (they are mine because I haven’t run across them in my research, fair enough?) are: (1) the blocks on the front of the jig to aid in holding the horizontal bar in place while it clamps the rails and also serving as stops to square the rail to the top of the jig. These blocks are adjustable with slots cut in the front of the jig. (2) the grooves cut in the router sled to align the router bit with the center of the mortise.
The basic materials used are 3/4” birch plywood, 1” Red Oak, black walnut runner, 3 – 5/16 knobs, 5 – 1/4” knobs, 2 – 1/4” thumbscrews, dual track from Rockler, plastic cutting board, rubber washers, several carriage bolts and pocket screws.
Thanks for viewing my latest project.
-- Makin' Sawdust!!!