I had been wanting to make a knife for a long time but hadn't for lack of material (i.e. good steel), tools and time. I needed a combination of the three and I reached that sweet spot when I found a piece of steel at work that looked promising and realized I could spend the whole weekend in my granddad's garage with his tools and the neighbors'.
This project took me a whole weekend, and I loved (almost) every bit of it. It included many things I never did before : metalworking is many things in one. I avoided heat treating and tempering by using a pre-drilled pre-tempered piece of metal. This is my first knife so bear with me.
Sit back, turn on some Shakey Graves, maybe grab a glass of Scotch whisky (if you're of drinking age. I you're under 21 in the US or 18 in civilized countries, your parents keep the god stuff on the top shelf) and you'll be set to read this instructables :)
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Step 1: Tools and Materials
As per usual, we'll start with a list of what we need. I came to realize that power tools, while still optional, can make the difference between a week-end project and a 5-year plan when it comes to working with metal. So they are listed as optional because they are, but they really, really make your life easier.
A piece of steel (Not stainless or Inox, High Carbon is better)
Some nice hardwood, different colors
Two-part epoxy resin
Files (Flat and round, rough and fine) I used my great-great granfather's files. It was emotional
Sand paper grits 40 through 600
Drill press or hand drill
Metal drill bit, 6 mm diameter
Wood drill bit, same
Optional tools (or power version of some hand tools)
Step 2: Blade Shaping
I used a leftover piece of steel I found at work but don't know anything about the composition or the hardness of the steel. I chose it because it already had two holes for attaching the handle and I did not want to bother with the drilling.
I researched blade shapes and designs online and drew a couple on my piece of steel with a permanent marker (erased with ethanol) before I was content with what I had.
I then cut out the general shape of the blade with a hacksaw and refined it with my great-great grandfather's files, which still have a nice grit regardless of their age.
Then I thinned the blade on the bench grinder. This step is probably the most delicate of the whole process as a slightly off angle can ruin all the work you did on the blade. Have a jar of water nearby to dip in the knife every couple of seconds of grinding : if it overheats, 1) you won't be able to hold the blade and might burn yourself and 2) You risk oxidizing the steel (the color shifts to blue, it starts fuming and you wont be able to sharpen the blade). Be extra careful on the tip of the blade and its thin parts as those will overheat very easily. As a rule of thumb, the thinner your metal gets the more often you will need to alternate between grinding and cooling in water.
Put the blade edge facing up so you can rest the back of the blade on the metal stand as you grind. Try to grind evenly and a little bit at a time, changing the side you're grinding so that the edge happens in the middle.
Do not worry about sharpening the blade just now, it will be much more easy to handle and less fragile.
Step 3: Handle
I used two different hardwoods to get a contrast : the core of the handle is made of boxwood (Buxus sempervirens) and the ends are made of an unknown piece of beautiful black hardwood found in my granddad's garage.
I sanded one side of the piece of boxwood so it would stand flat on the scroll saw and drilled three holes in the middle to make a slot the shape of the tang of the blade.
I then marked the place of the holes in the tang on the handle and drilled the wood. I glued a piece of wood on the butt of the handle and one on the other end with a slot just the size of the tang.
I drew the shape of the handle and cut it out roughly with the scroll saw then rounded it on the belt sander. I then sanded it up to 600 grit and plan on finishing it with a mix of paraffin oil and hexane 1:1 (the hexane helps the paraffin to soak in the wood and then evaporates slowly) when I get my hands on some of the stuff.
Step 4: Pins
The credit for those mosaic pins goes to Phiske and his intructable. Instead of brass, I used aluminum tubing and copper wire, filled the tube with three wires and added epoxy. Pretty straightforward. Looking back on it, I should have put four sections of copper wire instead of three but it's not that bad.
Step 5: Oxidizing a Pattern in the Blade
Credit for this step goes to ElmarsM and his instructable. I reproduced the motif from his knife because, although I do not belong to the Latvian culture, I found it beautiful. His instructable made me want to research his country and culture, you should check it out.
I got some FeCl3 powder and solubilized it in water (20g in 10 mL). You could use FeCl2 or an acid instead (HCl, H2SO4, HNO3...)
I made a mask with some tape and cut the pattern on it. I then deposited a couple milliliters of the FeCl3 solution and let it sit for a couple of hours. In retrospect, I could have concentrated the solution to saturation and let it soak overnight to engrave the pattern deeper. Heating will make the reaction faster at the risk of ungluing the tape.
Step 6: Attaching the Händel to the Blade
Using a little bit of epoxy on the tang, I put it in the handle and hammered the pegs in. I sanded them flush with the handle on the belt sander and finished them with 600 grit sandpaper.
Ain't got no pics of that step but it speaks for itself.
Step 7: Sheath
Using thin (4mm) dark wood with a hint of white on the outside, I cut three rectangular pieces of the same dimensions.
In one of those, I cut out the general shape of the blade such that it could slide in and fit snuggly. I sandwiched that one in between the two other with wood glue, then shaped the whole sheath on the scroll saw and rounded it on the belt sander.
This sheath is just for protection of the blade but I want to integrate it in a leather sheath with loops to render it attachable to a belt.
Step 8: Blade Polishing and Sharpening
I polished the blade with 200 to 600 grit sand paper and then a polishing drill attachment of unknown roughness. I coud have polished it more, removed all the imperfections to reach a mirror finish. To be fair it would have been really long. But doable nonetheless. I decided against it because I liked the rough look of the blade. I always thought shiny knives looked cheap and didn't feel sturdy. This knife will also get a lot of use I'm sure, so what's the point of making it too pretty for its task ?
I am by no means an expert on blade sharpening and could probably have researched the subject extensively before I started sharpening my knife but my week end was drawing to an end. I would be grateful for tips about sharpening in the comments.
On the grinder (or with a file), make the blade thinner on the end. Then give it an angle of 15 degrees (who asked if it was Celsius or Fahrenheit?) or as close as you can get on the last 2 or 3 millimeters of the blade.
When this was done, I used a sharpening stone, holding the blade at a 15° (aaaaapproximately) and making a movement such as if I was trying to remove a fine layer of the stone.
Step 9: Done !
There you have it. Your own home-made knife !
This was a very rewarding craft for me, I learned a lot of knew techniques and how to use new tools. I really enjoyed my week-end and did not see the time fly by.
Until next time !