Adjustable finger joint jig

I made this jig a number of years ago and used it on a few boxes right after I made it. It sat on a shelf for a number of years. The project I'm working on is a box that will be made from 1/2" thick cherry to make a storage case that looks like a brief case. It needs some really strong corner joints. I tossed around miter joints, splined miter joints, rabbet joints, locking rabbet joints, dove tails and finally 1/4 finger joints. I pulled out my old jig finger jig and figured out again how to use it. This jig originally came from plans in "Wood Magazine" (no I don't know what issue).
Here is the front and rear of the jig. Not the dark colored strip on the front of the jig. This is a replaceable zero clearance insert that stops all tear out as you cut the fingers. Each insert can be used at least twice depending upon the width of the fingers.
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The neat thin about this jig is the adjustability. You first decide on the width of the fingers and set up your dado set. Make sample cuts in scrap wood until you get the desired width of cut. Then measure that cut with calipers.
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Use that measurement to adjust the metal indexing tabs using the adjustment slide on the back to make them match the width of your cut being made by the dado.
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Then again using scrap pieces you adjust the distance between the cuts so the fingers are properly spaced. Using the second adjustment on the back. Once everything is set you tighten the knobs and start cutting fingers. I cut both joint pieces at once by off setting one piece from the other by the width of a finger. Your fits cut will make a finger on the piece against the jig and two slots, one in each piece.
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I didn't take photos while I was doing it so here is how you start a joint set.
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Here is a completed joint.
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The spacing on my first pair in cherry was a bit loose, so I made a slight adjustment and the remaining three corners were tight.
I learned from previous experience that it is best to make corner pairs to insure a better fit and to label each corner set so you can match them up as you assemble.

This jig has limits on the size of the fingers and spacing but for small finger joints it works quite well.