Hi Instructables Community,
this week it is time for a new afternoon project. One thing that annoyed me for quite a while when making pocket survival kits was that I never I had a fixed knife that would fit into a small mint tin. I know that there are a few small knives commercially available but I never really found one that I really liked.
Being a fan of Jimmy Diresta and his projects inspired me to give it a try myself. Here are a few links for you to get some inspiration yourself.
PS: Don't forget to visit the last step for info on my current giveaway!
PPS: To all the knife makers and blacksmiths, this is my first ever knife and I'm aware of its shortcomings and limitations so please don't be too harsh in your judgement ;)
Step 1: The Design
I had an old saw blade lying around and wanted to see if I could realize my idea with the few tools at my disposal. The design itself is inspired by prehistoric stone hand axes since I wanted a double edged knife. The handle (if you want to call it that) is shaped in a way that allows for different grips. The same goes for the two edges each of which has a different shape for different cutting jobs.
The blade fits easily into an Altoids mint tin and also features a lanyard hole that can be used to attach the blade to a short stick which could serve as a knife handle or on a longer stick to create a spear.
Step 2: Preparation
Once you've cut out the sketch use some glue to glue it to the saw blade.
Make sure you position it in a way that leaves some material around the edges.
Step 3: Cutting Out the Rough Shape
I used my rotary tool with a cut-off disk to cut out the rough shape of my knife.
I used many passes with light pressure and medium rpm to keep the temperature at the cut low. This should help avoid ruining the tempering of the steel through overheating.
Also try to keep your cuts outside the outlines as you will refine the shape in later steps.
You could also use an angle grinder for this task preferably one with variable speed control.
Step 4: Rough Shaping
Next I used my belt sander with 60 grit sandpaper to grind the knife into its rough shape.
I also tested several times until the knife actually fit into the bottom of the tin.
Step 5: Refining the Shape
I went up to 100 grit sandpaper to further refine the shape and also remove any rust from the two faces. The shape of the knife now pretty much resembles what I had in mind. The "handle" was also deburred during this step.
Step 6: Rough Bevelling
This step was a little more tricky since I wanted to try and roughly bevel the edges freehand.
I used 120 grit sandpaper and medium speed checking the angles after each pass. This way it took a little longer then with other methods (e.g. a jig for specific angles) but I wanted to develop a feeling for doing this freehand.
Step 7: Spot Annealing
Since the steel was already hardened I had a hard time (no pun intended) to drill a hole for a lanyard or handle attachment.
For this reason I tried a technique called spot annealing. Using a vise grip pliers to submerge the knife in water whilst using a blow torch to heat up a specific area.
In theory the cooling effect of the water should control the temperature and thus the knife edges should retain their tempering.
In the final picture one can see pretty well through the coloration of the steel where the tempering has changed.
Step 8: Lanyard Hole
With the handle section annealed I retried to drill a lanyard hole.
With some cutting oil I first drilled a 3mm pilot hole which was then enlarged to 6mm.
Finally a countersink was used to remove the burrs around the hole.
Overall this process seemed to have worked pretty well but only time and use will tell how well the blades will retain their edges.
Step 9: Sharpening Pt.1
I used my Proxxon Micromot Band Sander with 180 Grit sand paper to further refine the edges until I was satisfied with the overall geometry.
If you check the third picture you can see a very fine burr on the edge which will be removed in the following steps.
Step 10: Sharpening
A whetstone and a leather belt were used to sharpen and hone the two edges. Both require some practice but I think it is really worth to spent the time as the results will speak for themselves.
Step 11: Testing
I did a very simple test and tried to cut regular paper with the two edges. Overall I was quite happy with the results bearing in mind that this is actually the first knife I ever made.
Step 12: Putting the Knife to Use
The video includes a short demonstration on how to pack this knife into your survival kit.
Future modifications will probably see a second hole being drilled for sturdier attachment methods. I also want to try to create a protective patina with vinegar but that will be be a different Instructable/project.
Step 13: Giveaway
You can win a Leuchtturm1917 softcover notebook along with some quality sketch pencils, a few of my channel sticker and a 3-Month Instructables Pro Account.
All you have to do is to subscribe to my YouTube channel and leave me a comment at this video and include "I'd like one!" & your Instructables username. You have until the 15th June 2016 1800 GMT to participate after which I will announce the winner on my YouTube channel VLOG. (Only entries from the EU, Norway, Switzerland, USA & Canada are eligible to get the full package mailed (please understand that I pay for this myself), residents of other countries may only receive the Pro-Account).