This project combine the two things that I enjoy the most: knifemaking and aluminum casting.
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Step 1: Where to Start
In this video I make the knife from start to finish, I suggest you to watch it first: most steps are self explaining!
Step 2: The Blade
Trace the blade template on a piece suitable steel stock: I used 1070 high carbon steel 5mm thick since is easy to heat treat like most high carbon steel.
Cut the knife black with watever you have aveiable. I have a metal cutting bandsaw so of course I use that but any angle grinder with a cut off wheel or even an old hacksaw can do the job.
Drill some hole in the tang to reduece the weight and most importantly to give something at the aluminum to hold to later on.
You can find the template attatched here for free, I made it on cad following reference image found on Google.
Step 3: Grind Time
Tune up the shape of the blank and grind the bevels. Mark lines to help you out get consistent grinds.
If you don't have a belt grinder this can be done even with a regular bastard file and a file jig, there are many tutorial about making one.
Step 4: Hardening
The heat treatment will vary depending on the steel you are using, for high carbon steel like the one I use you just need to let the steel heat up over the curie temperature and quench the blade in oil. I used vegetable oil and a magnet to check the steel temperature.
Step 5: Shaping Foam for the Aluminum Handle
Using the template cut and shape the high density foam for the handle.
Then slice it in half and make a slot for the blade tang, I've used a broken hacksaw heated with a blow torch for that.
Step 6: Aluminum Casting
Combine the two parts already done and bury them under casting sand. Mine is an oil based clay, but there are also diy sand called "green sand" that work the same way.
Leave a piece of foam uncovered to pour the molten aluminum.
Step 7: Finishing
Temper the blade by heating it to 200°C for 1 hour. That might seem like a short tempering process but some of the hardness must already have been taken off by the molten aluminum at over 700°C.
Take away the sprue and start refining the aluminum with files and sandpaper. For extra shine butt if on the wheel when you reach at least 600grit with the sandpaper. On the blade I polished only the bevels, I left the other parts with scales from the hardening for estetic reason.
Step 8: Walking Dead Approved!
Feel free to ask me anything, this is my first instructables article so I might have missed some important stuff that I don't know about. Thank you for reading through the end :)