Pic. 27 The design of this knife calls for the front edge of the guard (other side of your index finger) to have a small curve. Here it is roughed in. It will be blended later as in Pic. 31.
Pic. 28 Close-up of the slot and how it was filed to fit the curves at the tang shoulders. Also notice how the shoulder face is forced into the guard on the spine side (top) of the slot. When the punch is used again, concentrate a bit on the choil side. Then you will have full contact between the guard and the shoulders, and have no gaps.
Pic.29 &30 Use a circle stencil that doesn’t cost much, (Ha ha.) to lay out the curve for the finger guard. Imagine extending the curve into the wood. Don’t remove too much material. The deepest part of the finger curve should lie in line with the underside of the choil. Besides wanting the flow of the design to look correct, when shaping the handle, you don’t want to break into the tang cavity. Ouch – Start the wood over!! We try to do as much shaping (within limits) as possible at this stage, because, have you noticed how hot the guard gets when grinding? If all this heat were generated once the wood was glued on, it wouldn’t be glued much longer!
Pic. 31 Flatten both faces on the disc. Blend in the curve on the front face from Pic. 27. Polish with finer grits (front face only) on the disc.
Pic. 32 Starting to look good.
Pic. 33 Hand sand the final grits up to say 1500# or 2000# but DON’T buff it yet. The buff will round the sharp corners of the slot, and once it is fitted to the knife, will cast a shadow and look like a gap – even if there isn’t one.
Pic. 34 & 35 File the slots in the decorative spacers. Deburr them too. Burrs will cause gaps in the fit-up. Flatten thin metallic spacers if you are using them. They should not be buckled.
Pic. 36 Now we start to prepare the wood block for its slot to accept the tang. Orientate the wood to take best advantage of the wood grain, including character you want and avoiding cracks, flaws and less exciting areas of wood grain. Lay out the template on the wood and position the tang neatly in the middle of the shape. The wood I have chosen is African Wattle burl (Peltophorum Africanum) Note: These pencil lines are just guide lines, and are temporary. What I mean is that once the hole has been drilled and rasped into the wood, its actual position may have changed a little. Mark the tang hole a little deeper than needed. You don’t want the tang to bottom out.
Pic. 37 Transfer the dimension of the tang around to the end of the block. Also draw a center line.
Pic. 38 & 39 Set up the 4mm long series drill in the drill press. Clamp the wood in a drill press vice, with one side of the tang in line with the drill. Drill the hole to the required depth. You can put a bit of masking tape on the drill to indicate when you have reached depth. Take it easy. Stop regularly to clear the shavings from the drill bit. Oily woods are particularly prone to gumming up the drill, especially as the hole gets deeper. A gummed up drill will start to smoke, and the heat can cause the wood to crack. Also a gummy drill will prefer to follow the direction of the wood grain instead of drilling straight. Let’s not go there! Clean the drill often. I have a sharpened brass rod to use as a pick. Line up the other edge with the drill and repeat with the other hole.
Pic. 40 -45 Long series drill in 4mm size and tang rasps are used to rasp out the hole in the wood until the steel tang fits neatly into it, with a little clearance all around. The hole should be a little deeper than the tang is long, so that there is no chance that the tang will touch bottom when all is clamped up. It is not good form to simply drill a round hole into which a rectangular tang fits. Yes, I know that with some of today’s modern epoxies, this might be OK. But what will it be like 50 years from now? The rasp in Pic. 44 is a mini rasp that I bought in a set from a jewelers supply store, called a wax rasp, used for making wax moulds for castings. You can make your own by slowly grinding down a coarse file to size, without overheating it.
Pic. 46 & 47Mark out the front face of the wood and carefully grind it down until you get a perfect fit against the guard. Ensure the guard is properly in position against the shoulders when doing this. Don’t only focus on the fit along the “long” dimension. Also check across the “short” dimension. Do this fit check without the decorative spacers in place.
Pic. 48 – 50 Erase the temporary lay out lines. Re-draw them in their correct positions, by lining up the template over the blade.
Pic. 51 You may grind in a few notches in the tang to increase the grip of the epoxy. Be careful of their position in relation to the hole that will be later drilled for the pin. They should also not be too deep or so many, so as to weaken the tang strength. Be sure to roughen up the tang with a rough belt to remove any traces or heat treat oil and fire scale, also to increase the glue grip. I could argue that if you use a quality epoxy the notches are superfluous, especially since there is a pin holding everything together.
Pic. 52 & 53 Clamping option 1. A wood workers clamp that is long enough works great. Do a trial fit up to make sure everything goes together as it should before you mix the glue. Make an aluminium or strong plastic block for the tip of the knife to bear down on. There is a hole drilled in it so that the force is not directly on the tip. Hard wood blocks or brittle plastic should not be used. They may work for a bit, but are going to break when you turn your back on it one day releasing the clamping pressure, and the knife will fall to the floor! How do I know this? Notice there is a slight angled point on the very top end of the wood block. This is to focus the downward pressure in line with the tang. If the pressure is out of line, the wood and knife assembly will kink out of alignment, and you will find glue gaps once you start to shape your wood. One only has to exert moderate, positive pressure. If all the fits are good everything will be OK. A bad fit won’t be fixed with extra clamping force.
Pic. 54 a-c Clamping option 2. This one you will need to make if you don’t have a long wood workers clamp. It is not difficult to make. I have used tough wood with leather to line the wooden jaws, to give it grip against the knife and give it a slightly padded cushion against the blade. 6mm thread bar and nuts with washers complete the gadget. I have used a piece of flat bar to clamp down on the wood when the nuts are tightened. Don’t over -do the nuts. One has immense strength using a spanner. One only has to exert moderate, positive pressure. If all the fits are good everything will be OK. A bad fit won’t be fixed with extra clamping force. Make sure you pull up in line with the tang, for reasons explained just above.
Pic. 55 & 56 I have successfully used “ABE Epidermix 372” for years. It is a slow curing epoxy, giving you time to “get your ducks in a row”. A fast curing epoxy forces you to rush the assembly and clamping procedure. You will only be able to continue working on the knife the next day (earliest).
Pic 57 & 58 Once the clamp is tightened up, clean off ALL the glue that has oozed out. I said ALL!! Go as far as wiping down with acetone on a tissue. You don’t want any hard glue left on the blade later. It can be a bugger to remove when it has cured. Concentrate your efforts in the corner where the guard and blade meet.
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