Fundamental Woodworking Joints Pt. 2

There are number of ways to make a mortise. And this is pretty much the way that it is use to be done. You can even use a drill press and a force rivet to hug out most the material and chisel the way the rest. Well, I could use my feet to go down the road like Fred Flintstone in my car if I wanted to, but sometimes you just needed to take advantage of technology. And I find that when it comes to making a mortise and tendon joint. Power tools are the fastest and the most accurate way to go. That does not mean that you should not learn to do this process with hand tools, in fact, practicing some of these classic techniques is a great way to improve your manual dexterity in confidence with hand tools. Most of you probably on a router. So, this particular method is likely to be the most feasible options for you. And I prefer to use up-spiral straight bit for creating my mortises. And up-spiral bit gives us more efficient cut, because it pushes the wood chips up and out of the hole. The disadvantages that the up-spiral bit may also tear out some of the wood fibers near the top of the mortise. But with the good sharp bit this is usually is not a problem and even if there is a little bit tear out of the most likely be covered by the shoulder of the tenon. You can use a down-spiral bit if you have one but, they are better suited for shallow holes. I actually need to get a new up-spiral bit, so, I am going to use my standard straight bit for now. Alright, let us set up for a mortise cut. [Music Playing] I begin by attaching an edge guide to the router base. [Music Playing] Using double stick tape, attach a second board to the mortise board. This gives my rounder the extra support that it needs to stay balanced and safe. And then clamp boards between two dons in my work bench. After marking the locations of the mortise using a pencil and a straight edge, I carefully set the straight bit right to the pencil line. [Music Playing] After bringing the bit down to the surface of the wood, I use the built in depth gauge and stop to set the plunge depth. [Music Playing] With the safety gear on and the dust extractor attached, it is time to start routing. Now if the depth of the mortise is greater than three quarters of an inch, you may want to consider making the cut in two passes. [Music Playing] And when you are done, you should have a nice smooth walled mortise. Now, you will notice that I did not stop locks; I simply routed to my lines. These makes this set up go a little bit faster, and if I go over the line by a 30 second of an inch, it is not really is not going to make all that much difference. The joints got to be just as stable. And one of the thing to notice the fact that the mortise now has round edges that means we will either have to round over the edges of our tendon later or we can square up the corners of the mortise with a chisel right now. I prefer to round over the tendon, call me lazy. I would also like to mention that you can certainly use your router table to make a mortise. But, that usually requires slowly dropping the work piece on to a moving router bit, which is not exactly my favorite thing to do. So, if you can avoid it, you are probably better off taking the tool to the wood rather than the other way around. Ever wonder if you can drill a square hole? But with this machine you can. This is a hollow chisel mortiser, and you can find this for, I would say as little as $200.00 and probably even cheaper, if you find a used one. It is a one trick pony but when that pony’s trick is not essential wood working task, like making mortises, it is really a good investment. Now this machine uses a special boring bit that is housed inside of a four sided chisel. Now as the bit hugs out the bulk of the material the chisel slices the hole into a nice even square. Let us do a sample cut. [Music Playing] Setting up the motiser is easy. With a pair of gloves on, I insert the bit and the chisel. Keeping the chisel about an eighth of an inch from the top, I then tighten the chisel and the bit into place. Once the bit is secure, I raise the chisel to the top. This technique results in the bit for protruding just the head of the chisel, which results in a much more efficient cut. Placing a piece of scrap against the fence, I rotate the chisel so that it square with the fence and the open end of the chisel faces either to the left or to the right. This allows the wood chips to exit the hole, reducing friction and reducing heat. Using a motor series a lot like using drill press, but requires a lot more pressure. In fact, most people are quite surprised by just how much force it takes to plunge the chisel through the wood. If you have notice my bulging biceps in previous episodes, now you know why. Seriously though, I actually broke the bulb joint on my motiser once simply because I put way to much pressure on it. The culprit, adult chisel. So work to the lines, keep your chisel sharp using a cone shape diamond stone. That is a damn using alders. So, it cuts up like butt up. [Music Playing]