Now, one thing you are always going to have to content with when you are cutting dovetails is the war on tear out. Okay, when you are actually running through boards like this, the grain which is running vertically can very easily just crack and bend down. So, this can be a very big problem especially on splinter and nasty woods like wangy. It is a real problem. So, what I usually do to combat that I got a few tricks and I will show you those in a bit on the jig itself but just sort of stock the cards in my favor, it would be nice if I could do something at this stage to prepare this piece. One thing that you can do is use one of the traditional scribes to actually scribe a line at the exact point where that bit is going to plunge through and what then I will do is severe the fibers in that location and then make for a pretty much the smoothest possible cut you can get.
Alright, so let us do that really quickly. I start by using my side piece as reference because I want to know what the exact thickness of that side piece is. And then I am going to transfer that thickness to my front piece. Now, I am really only concerned about the outsides because it is really where the most visible area would be where tear out can occur and in most cases, that is going to be actually be the exit side on the jig do it is important that we scribe on those location. Okay, so it is very simple, you just run it along the edge, okay, and so as many, you know, take your time, do as many passes as it takes juts to make sure you saver those front fibers like that.
So now we need to set up the actual arrangement of the pins and tails on our board and some jigs are more flexible than others. Some do not give you any flexibility at all. For instance the ekita is only flexible in terms of 8” increments. What makes the Leigh such a great jig and there maybe a few other out there but I know one of the hallmarks of this jig is the fact that it is infinitely adjustable. So let me show you how we are going to do that real quickly.
I am just taking one of my side pieces which would be one of our pin boards and I am bouncing it into the jig, bring it up to the bottom of the guide here. So this is the template, this little fingers dictate what we are actually going to be doing for the operation. The angled ones here, these are going to be from where we are cutting the pins to side pieces and the other side, you flip it over are for one we are doing the tails.
Okay, so even though we are actually going to cut the tails first, in order to setup our design, I am going to use this side, I am going to use the pin side because I can actually visualize what the joint is going to look much better on the pin side than I can on the tail side. So, just slide, the fingers on for the jigs, it helps if you slide both sides at the same speed, okay and I am going to lock that guide in place. Okay, so now once we are in position, we are in a great situation here where we could look from an overhead view and see what the shape of our joint is going to look like.
Okay, now these all separate and they move freely. That is the infinite adjustability here and they tighten down with that little screw head there. So, what you want to do is make sure we ignore this first one and we are going to ignore the last one. Okay, these are actually both just for extra support as the router sort of moves off the space here. Okay, so since this is the pin board, I am sure of you had heard people say that you always want to start with a half pin on the side. Meaning you want wood here and you want wood on the end here that gives you ultimate strength and it also ensures symmetry.
So, what I would like to do is I make this little finger pretty much even with the outside of the board here. A lot of times, you could just eye ball it, it looks like maybe a 16th of an inch of wood as exposed in the side here and I am going to push down on the finger and lock that guide down. Now, I am going to do the same thing on this other side. That should be it so let us mark this with a pencil so that we could see where we are at. We could always make adjustments later. That looks a little bit better. It is more spacing, proper spacing so you got half pin, little pin, big pin, big pin, little pin, half pin. Okay, that is the arrangement we are going to go for, I like that.
So now that we have our spacing set, we can remove our pin board because again, we are cutting tails first. And again, this is the pin side so I need to flip this guide over, we are going to go to the tail side and insert our tail board.
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