On this Join It episode, I show you how to strengthen up one of the weakest joints in woodworking. The miter joint has many downfalls, but with a little added support from a spline you can incorporate contrasting species of wood to add so much more beauty.

To start, you need to cut a 45 degree bevel on what you plan on making the joint from. In this demonstration, I used a small 1 1/2” piece of poplar with two opposing bevel joints.

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Next, I squared up the ends to make them equal (again, for demonstration purposes only)

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Now, just glue up the joint and let the glue set up.

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Once you have a cured joint, use the saw blade and a spline jig (for more information on this jig you can visit: pass the joint through the blade one time to create the mortise for the spline.

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Using my brass 1/8” bar, I set my tenoning jig up 1/8” away from the blade, because the mortise made earlier was 1/8” wide. Set the blade high enough to cut a spline big enough to fill the mortise.

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Then just free it up from the stock using your SCM saw or your table saw.

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Place the spline in the mortise with glue and clamp pressure to make sure it is fully seated in the mortise. This will avoid any gaps from not being properly seated.

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Once cured, run the spline excess through the saw to get it as close as possible to the surface of the stock. Sand it smooth to finish it up.

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I hope you all enjoyed this episode and I hope you can incorporate this joint into your projects. Please remember to be safe in your shops and I will talk to you next week.

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Also, don’t forget about my big sale running through the end of the month. Use codes BOOM20 on all my plans and BOOM50 on all my apparel. You will get 20% and 50% off respectively. BOOM!!!


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