# Large Shop made Dovetail Spline jig



## WalkerR (Feb 8, 2017)

I'm working (very slowly) on a kitchen island project that has spawned several side projects. It will have a cabinet built into the bottom which I wanted to do some dovetails on. However, the way I cut my panels I ended up with edge grain on the corners instead of end grain, which I've since learned is no good. I then read about mitered corners with dovetail splines, or "Faux dovetails". Sounds like a good solution. Since I've never done them before I wanted to try it out on some less critical stock. My wife wanted an indoor planter box, so I threw one together real quick (two birds, right?) and proceeded to make this jig.

I looked at some plans for dovetail spline jigs. Most of them seemed better suited for compact routers, and only allow one cut at a time. I needed something solid enough for a larger router- I only have one router, a Bosch 1617 and I wanted a jig that could do large corners without having to constantly move and re-clamp. I do have a router table, but my fixed base for the router seems to have some issues with height adjustment, so for now I'm stuck with just the plunge base.

I put this jig together with scrap laying around the shop. Here's what I came up with:

After squaring up a piece of birch ply, I laid out the cuts as well as where the brackets will attach. 

















I routed out slots to accept a 3/4" O.D. guide bushing. The bit I'll use with this is 5/8" diameter. I spaced it so that there will also be 5/8" between each spline, for a nice even look. Of course I could still re-position the jig if I wanted different spacing. The slots outside of the brackets allow for getting the spline closer to the end of a box.

I carefully cut the bracket pieces to 45* angles and attached them with glue and screws. To assist with the positioning, I clamped a straight scrap piece on the center line, and put the whole thing in my vice. I pre-set all of the screws as well, to free up a hand. Made sure to countersink the screws so the router base won't catch on them.


















I attached some more scrap pieces across the brackets. They stiffen the whole thing up as well as aid in clamping the jig onto the box. Another added benefit is they are the same thickness plywood and I left a gap between pieces, so I can use it to set the zero depth on the router bit.


















The jig will handle joints up to 24" long. Move it/re-clamp just once, and you could get the spaces left by the brackets. This particular box is only about 7". The results turned out pretty good! Aside from my terrible miter joints, and my imprecise cutting of the splines (both of which I'd blame on my entry level table saw, but we're not allowed to blame the tools right?).


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## Woodchuck2010 (Jan 19, 2016)

Thats awesome!


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## Peteybadboy (Jan 23, 2013)

Walker, nice spline jig. Today I saw a jig from infinity tools to make the spline on the table saw. How do you make the dovetail splines? I think I can make their jig but I am looking for ideas. Nice jig .


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