Okay, today I will be showing you all how to make a habaki! Before I get into the actual process, I'd like to do a little overview on what a habaki actually is.
Okay, so a habaki is basically a little copper collar that is used on many japanese knives. It's purpose is mainly to hold the wooden tsuka (or handle) firmly in place. It allows the tsuka to be affixed with only a single bamboo pin and no adhesive. This in turn allows the entire knife to be taken apart for sharpening and maintenance. In the pictures, I tried to show a picture of what it looks like, how it fits on the knife, and how the tsuka is mounted behind it. I don't have a knife with me right now that needs a habaki, so in this instructable I will be making a tiny one that will become a necklace. However, the process will be comparable to making one that actually fits a knife.
Step 1: Materials and Tools
To make a habaki, you will need the following tools and materials AT THE BARE MINIMUM:
*Copper, ~1/8" thick, the other dimensions will designate the height and width of the habaki
*Hard Silver solder. if making it for a knife, it is very important that the solder be hard, as the habaki may be put under a considerable amount of stress
*Some form of flux. I personally use borax, a cheap laundry detergent
*A burner capable of achieving soldering temperatures. I use my homemade propane forge burner
*Files. Preferably a double cut and a finishing file
*A hammer and a hard surface
*Pliers (for bending the copper)
*A hacksaw (for cutting the copper)
*Water in a cup or bucket
*Proper safety atire such as gloves, eye protection, and a respirator
Some things that really help are:
*A belt sander
*A homemade habaki making tool. I will explain this in a later step
*Lots of sandpaper (for polishing purposes)
*Flitz metal polish (for polishing purposes)
*A buffing wheel (for polishing purposes
*A jewelers saw
*A little superglue
That just about does it. The items in the first column are a NECESSITY. The items in the second column are very useful tools that make creating the habaki easier, but can be worked around if you don't have them. Now we're ready to start
Step 2: Cutting and Rough Forming of the Copper
Okay, in the first picture you can see the copper stock that I start with. It is ~1/8"×1.5". Using a hacksaw and a vice to hold the copper, I cut out a piece that is about 1/8"×2,3/8"×3/4". If you don't have copper flat stock, you can use scrap like copper pipe or sheeting. Make sure to add a little extra length to what you want the final dimensions to be, because some of the copper will have to be ground or cut off during the process. My habaki ended up being a little over an inch tall and a little under 3/4" wide.
Now you have to mark the center of the copper piece. I use a sharpie to mark the center line.
The habaki now needs to be folded in half.
*Note that if your copper is very stiff and doesn't bend easily, it will need to be annealed. I explain this in the next step.
I personally use a special habaki making tool. It is basically two u-shaped pieces of metal welded onto a flat plate. A punch made of mild steel flat stock (that is roughly the same thickness as the spine of the knife the habaki is for) is then hammered down onto the copper. Walter Sorrels has a great youtube video that explains this tool better than I can, but you will need a forge and a welder to make it.
For those of you that don't have the tools to make the habaki tool, there is another option! You can simply use two pliers to bend the copper. place the pliers on the copper like in the picture. make sure that they are as far apart as you would like the gap in the habaki to be. For example, if you are making this for a 1/4" thick knife, place the pliers so that they are 1/4" inch apart on the copper. Then simply bend the copper ends towards each other.
Whichever method you use, the copper will stiffen up and become work hardened partly through the bending process. It will need to be annealed before it can be bent fully, as explained in the next step.
Step 3: Annealing (or Softening of the Metal)
So annealing (for copper) involves heating up the metal and then rapidly cooling it. This basically resets the grain of the copper and greatly softens it. To begin, I cut a piece of iron wire and wrap it around the copper. Then I wrap the wire around my tongs. Any long piece of metal can be substituted for the tongs. I then clamp my burner in a vice and light it. I hold the copper in the flame until it is an even reddish-orange color. Then, I immediately dunk it into a bucket of water. After this, the copper should be noticeably softer. If you can't bend it with your fingers, you've probably done something wrong and will need to repeat the process.
Step 4: Further Forming of the Habaki
Now I continue to bend the copper. notice how I add extra scrap metal pieces in the habaki tool in order to get the habaki to tightly fit around my punch.
Doing this part with only pliers and no punch can be quite difficult. In the end, you may have to file the inside square or just leave it rounded, because it will be very hard to get a perfectly squared habaki without the punch.
After I get my habaki so that it has two 90 degree angles in it (as seen in picture 6), I usually will anneal it one more time. See step 3 for the annealing procedure
I then close the habaki almost all the way with either a hammer, pliers, or just my fingers. If this is being made for a knife, make sure to close the habaki by hammering it while it is on the tang of the knife. Leave a little space so you can sand the oxides off near the bottom, like in pictures 9 and 10. Later on, you will need this part oxide free so you can solder it.
Close the habaki fully. Chances are, the sides and bottom of the habaki are not perfectly aligned, so take this opportunity to file them square, like in pictures 11, 12, and 13
Step 5: Break Time
You've been working hard, and are probably more than a little hungry... Smores anyone? :)
Step 6: Munemachi Notch
This allows the habaki to be tightly fit around a knife, and also allows the habaki to cover up the very end of the edge of a blade, which is important for the next step.
I start by cutting two guidelines in with a jewelers saw. This is not necessary, just a personal preference. Then I clamp the habaki to a table and find a file that is equal to or less than the width of the opening in the habaki. For example, this habaki has a 3/16" gap at the top. so I used a file that was a little over 1/8" thick. I then filed a notch in following the guidelines I cut. I then finished up the notch with some needle files
Step 7: The Machigane
This tiny little piece can be the most annoying part of the entire process. When I am fitting a habaki for a knife, it can take 30-60 minutes of fiddling just to get this thing to fit exactly right.
The concept of the machigane is a little difficult for me to explain, so I added a picture. Basically, the munemachi notch that we created in the last step and the machigane are supposed to add a surface that the hamachi and munemachi can rest against, allowing for a very tight fit.
Anyway, to make the machigane I start by cutting off just a little sliver of copper. It ended up being a square rod that was about 1/8"×1/8"×1.5". Then I started cold forging it. I added a bevel so that the square piece of copper became sort of wedge shaped. As you can see, beveling one side caused the spine of the machigane to curve back. To straighten it out I placed the machigane edge up on my surface and gave several light taps to the edge. You may have to bevil the edge again after this step, and make sure that the edge is paper thin when you are done.
Now the front side of the machigane that will be resting on the hamachi may become a little rounded during this process. I went and filed the end square as you can see in photos 10 and 11.
Step 8: Machigane Fitting
So now the machigane gas to be fitted into the habaki before it is soldered. I am only using this habaki as a necklace, so I just kind of shoved it in there, but if you will be using this for a knife, there are a couple extra things to do:
1) the machigane should be fitted while the habaki is on the knife. make sure that the habaki can slide up and down the tang and fits tightly and snugly against the machi on the knife.
2) make sure that the spine of the machigane is squared and fits snugly to the bottom of the tang without any gaps
now that you have the machigane in the habaki, I like to add a tiny drop of superglue to the back to hold it in place while soldering. then I cut off about 90%of the metal that is left sticking out.
Step 9: Soldering
To start the soldering process, I normally wash the habaki thoroughly with hot water. This will remove any dirt and oil that can prevent good flowing and joining of the solder.
To do the actual soldering, you will need:
*Hard Silver solder
*A couple containers for holding everything
If you are using borax as a flux, start by pouring a little into a cup. Add a little water and mix it up. It should form a thick, sandy paste.
Now you need to cut the silver solder into tiny little pieces. You don't need much, just cut a little section that fits onto the pad of your finger into pieces that are approximately 1/8"×1/8".
Now wet the end of a toothpick and use that to pick up the silver solder pieces. Pack them into the habaki, try to spread them evenly around and on top of the machigane. Now take a little dollop of the flux paste on the end of a toothpick, and spread it evenly over the silver solder. This will eat away any oxidation that occurs during the soldering, allowing for a good join.
Now tightly wrap the outside of the habaki with iron wire. This will stop the bottom of the habaki from opening up while it is being heated. Thread another wire through the top so that you have something to hold onto while it is in the flame.
Turn on your burner and put the habaki in the flame. The water in the borax will almost immediately vaporize. Next, the flux will melt and coat the solder and joint. Finally, when the copper is glowing a bright orange, the silver will melt and flow into the joint. You want to watch for this and when all of the solder is melted, pull the habaki out of the flame. Wait for the color to go down to a dull red (silver can fracture if quenched too hot), then quench it in water. If everything has gone right, the silver will have formed a clean joint between the habaki and the machigane, permanently closing it.
Step 10: Grinding and Shaping
Okay, this is where some form of belt sander is going to come in very handy. You can definitely do this with just files, it's just going to take a lot of elbow grease.
Anyway, right now, the habaki is technically functional, but it looks very fat and clunky and is covered in oxides. A good habaki should be tapered from top to bottom, AND from the back to the front. See pictures 13, 14, and 16. Notice how the front of the habaki is much thinner than the back. A good habaki should also have a top that matches the spine of the knife. I chose a triangular domed top called iorimune for my habaki. See pictures 9, 10, and 12 for further details.
The actual process of shaping the habaki is actually really simple. It just takes a lot of time and effort. Whether you are using files or a belt sander, to get the main taper just put extra pressure on the front of the habaki. I do all my angles and tapers by eye, but feel free to mark where you want the angles and tapers to be if you feel the need to. Also, if you are using files, make sure to use a finishing file to remove the deep scratches from the double cut file. If you don't, the polishing will end up taking A LOT longer
Step 11: Polishing
There are countless different types of finishes that people use for habaki. Here I'll just be doing a simple mirror polish. There are 3 ways you can do this:
1) With a buffing wheel. This is the simplest and most used method by jewelers. However, most people do not have buffing wheels.
2) Traditional polishing using soft wood cinders, stones, and water. This is very difficult and I do not recommend it for beginners
3) Sanding and metal polish. This is my personal technique, and I know very few people use this. It produces an amazing finish with minimal materials
I have the materials to do all three of these techniques, but I personally prefer the third, and that's what I'll be showing on this instructable.
So you will need sandpaper in 150, 320, 1000, and 2000 grit. Copper is soft enough that I can get away with skipping a couple grit steps, something that I would not be able to do with steel. You will also need a metal polish. The absolute best metal polish on the market is Flitz. I use it for just about every metal thing I make.
Okay, all you have to do here is set a square of sandpaper down on a clean, flat surface and then rub the surfaces of the habaki on the sandpaper. Alternate sanding directions, so every time you go up a grit, you should sand perpendicular to the previous grit marks. My habaki has 7 different facets, and I sand each one individual on each grit. Take care not to roll the geometry lines, you want very crisp angles and facets. Once you get to 2000 grit, the metal should feel very smooth and be shiny, but you won't be able to see a clean reflection. This is where the Flitz comes in. Dab a very, very small amount of flitz onto a clean cloth and buff the copper perpendicular to the grit marks. The flitz should turn black. once you've gotten all the surfaces, buff the Flitz off with a dry portion of the cloth. BOOM! Instant mirror finish. Your habaki is done
Step 12: Finished
I ended up hanging this habaki on a copper chain so that it would be a necklace.
Also, copper will corrode if left to the open air. I normally oil or wax them to prevent unwanted oxidation and try to avoid touching it with my bare hands as much as possible. If it does oxidize, no worries. Another application of Flitz will take off the oxidation and restore it to a mirror polish.
Alright, thanks for reading my first instructable! I hope it helps, and I'd love to see pictures of everybody's habaki in the comments. I will be entering this instructable in the metals contest, please vote for me if you enjoyed this or found it useful.
Happy Habaki-ing! :)