Others can do this via a power tool of some sort….tablesaw + jig….Router table + jigs…..But, you tend to be limited by a couple things…..width of whatever cutter(s) used, and a set spacing from the jigs…..
So, IF I want to vary the spacings, or have a single wide finger in between all the rest….Hmmmm…plus, all the set up times….and if the width of the boards does not match what the jig needs, for the fingers to come out right….
So…First I need a “spacer”....to mark out the finger spaces..
I use the chisel that will be doing the chopping…6mm width. Square is for carrying the markings all around…plus a baseline…
I usually start in from both edges, working towards the middle. In this case, I also wanted to have a lid to saw free of the box…so, about where the lid and the box will meet up, there is a double finger. Normally, I also do 2 of the longer sides first…just one end will do…I can transfer the markings as I go along…more layout tools..
This is set to the thickness of the ends, to mark a baseline. Working on a single corner, now..
I slide the board down low in the vise, less vibration that way…
Leave the lines, split the lines, cut out the lines….does NOT matter here…as what will be left will be how the matching fingers will be marked out to….
I have a piece of 3/4” plywood, I clamp it and the board to the bench, right over the bench’s leg. No bouncing allowed. Show face first…chop a bit, maybe 1/2 way down….more to prevent any blow-outs from marring the good side….then..
Flip the board over and complete the chops….both times, I use a marking knife to make a knife wall out of the baseline…
Gives a place for the chisel to start/stop at….one whack into the knife wall (lightly!) then peel a bit of waste out, letting the chop stop the peel. Then repeat as needed…
Then use these fingers to lay out the matching fingers….sharp pencil is required….then repeat all the above steps to mark out the waste, saw the waste (on the waste side of the lines) chop the waste…and see how well it fits..
However, IF you do not leave the lines, or split those lines….you might wind up with a few loose fingers….
I had to turn this end piece 180…corner #1 became corner #2….while I cut a new & improved Corner #1…leaving all the lines, this time…..can always pare a bit for fit….Then old #1 was used to lay out it’s new matching finger in the other long side..
Trace around around…cut, leaving the lines…test for fit..
Might get the hang of this, someday….then Corner #3…
Getting better…have to keep track of that fat finger…so that all of them will line up…#4?
Also..it helps to mark which corner is which, and which will be the inside of the box..
Tends to help during a glue up, too
Which will be in the next exciting episode, so…
Stay tuned..