A common uses for tenoning jigs is making tenons for furniture joints. But a tenoning jig is handy any time you need to secure the workpiece in a vertical position for a special cut.
You can purchase a professional grade tenoning jig for prices starting around $100.00. These . jigs enable you to position the workpieces in pretty much any way you want it. Plus, the jigs usually tilt for angle cuts.
If you don't have a need for something that elaborate, you can build your own tenoning jig that provides both the accuracy and versatility you need.
This jig mounts on your table saw sled and can be set to the exact distance from the blade you need.
Attach the End Stiffeners, Middle Stiffener, and Vertical Braces with 1 1/2" #8 flat head screws through the bottom as shown above.
Be sure the edges of the stiffeners and braces are flush with the edges of the base.
Insert two 1" #8 flat head screws, (1 1/2" will be too long) up through the bottom to attach each Knob Risers.
Be sure the 1/4" bolt holes, (indicated by red arrows), line up with the holes in the base. The Knob Risers keep the bolts straight so the Tenoning Jig slides smoothly.
Apply glue to the back surface of each of the front panel pieces.
Position the Front Panels, and T-Track on the Front Backer Board as shown above. Make sure all pieces are flush on the edges and clamp in place. Verify position of screw holes!
When the glue is dry, drill all the screw holes through the Front using the same drill bits you used when drilling the Front Panel. The reason for this is that the screw threads must grip the backer board, they must grip the braces in the back side of the backer board.
Place the assembled parts on a flat surface as shown above.
Attach the Front to the Braces and Stiffeners using 1 1/2" #8 flathead screws for the panels and 1 1/2" #6 flathead screws for the T-Track.
Make sure no screw heads are above the surface of the MDF. The surfaces must be flat for your Tenoning Jig to provide accurate cuts.
Position the Top Stiffener as shown above. Hold it down firmly against the Vertical Braces and and secure it to the front with three 1 1/2" #8 flat head screws.
Next, secure the Top Stiffener to the top of the Vertical Braces with the same size screws. This will ensure a flat work surface for your tenoning jig.
Apply glue to mating surfaces of the Handle and Handle Brace.
Position the Handle and Handle Brace on a flat surface with the Handle Brace centered in the back of the Handle. Secure them with two 1 1/2" #8 screws as shown in the drawing. (Flathead screws are not necessary here.)
Position the Handle as shown above so it is centered side to side.
Hold it firmly against the Knob Risers and secure it to the Knob Risers with two 1 1/2" #8 screws.
Insert five 1 1/2" #8 flat head screws through the bottom to secure the Handle and Handle Brace.
Check all the bottom screws and be sure none of the screw heads sit above the bottom surface. This is necessary so your Tenoning sits flat when in use.
(This step assumes you're using T-Track that uses 1/4" bolts. If not, use bolts and knobs that fit your T-Track.)
Insert a 1/4" by 2 1/2" bolt from the bottom up through each of the Knob Risers. Next, screw a 1/4" threaded knob with a 1/4" flat washer under it.
Using contact cement, glue 100 or 120 grit sandpaper to the Front Panels as shown above.
The sandpaper is not absolutely necessary but it helps hold the work piece securely in place.
Congratulations! Your Table Saw Tapering Jig is Complete!