Here is a photo of a jig I built for cutting spline slots in the mitered edges of stock used for small boxes. The jig is adjustable and can cut a slot centered in stock from about 1/4" to about 3" thick. I got the idea for making the jig adjustable after looking at plans for an adjustable cut-off/miter sled in a recent copy of ShopNotes. I have a few more photos in my photo album.
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