# Cut both box joint pieces at once?



## Fretts (Jun 12, 2010)

I am posting what could be a pretty dumb question here, but here goes...
I bought an extra metal template for 1/4" finger joints.
Why can't I cut both mating pieces of a box joint at one pass in a dovetail jig, such as my el cheapo Harbor Freight jig? Half blind dovetails are mentioned everywhere with both pieces in the jig...but not cut-through box joints / finger joints.
I'm looking at my pencil sketch of two pieces at right angles as I expect them to go into the jig, and I don't see why this approach isn't even mentioned, or why it wouldn't work.
I appreciate that you can't rout into the steel of the jig, but why not shim the work piece up off the steel surface with some plywood or scrap, position the vertical piece to mate with it, and blast through both pieces with a long, straight bit? So it digs slightly into the scrap under the horizontal workpiece, but so what? It looks good on paper, and in my twisted mind... but what am I missing here?
Thanks guys...
--Fretts


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## malb (Sep 15, 2008)

If you set the boards at right angles in the jig, (one vertical and one horizontal), and get the offset between them correct, it might work BUT, while the teeth in the vertial board will have a flat bottom cut by the end of the bit, the teeth in the horizontal board will have a round bottom because they are cut by the (curved) side of the bit. Will look a bit odd when assembled.

This is not an issue cutting dovetails because the template rounds the exposed (in the jig) face of the board to match, and then it is all hidden insde the corner.


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## Fretts (Jun 12, 2010)

Thanks for the answer!
In my case, none of this shows in the finished product; I am only interested in a very strong corner with no bracing blocks needed. The boxes get covered in tolex and any gaps are filled with wood filler, so I suppose this will work after all.
Why haven't I just tried this yet? I am still excavating a workspace in the garage and have no place to set up yet!


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## 4DThinker (Feb 16, 2014)

I've cut finger/box joints two boards at a time using a template that came with my porter cable jig. Using 1/2 inch thick boards, with one offset by one finger width clamped vertically behind the other. That was a few years back though as now I cut them using my CNC with the boards clamped vertically under the spindle. Far more variety in finger spacing is possible using the CNC. 
4D


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