In the Diablo game, the fetishes run at you with giant knives. The effect in the game is actually kind of terrifying and exactly the inspiration for the Steampunk Tiki, therefore I needed a giant knife. I wanted the knife to look handmade and made in a jungle type area, so specifically not modern steel. I decided that the knife blade should look like flint knapped obsidian. While I have flint knapped previously, I am not great at it and it does create really shape knives. Since this is for cosplay, I wanted the knife to look flint knapped but be dull so as to not harm people around me. I decided on resin casting for the blade. To create the mold, I first made paper clay blades halves. I then poured 2 part silicon rubber mold material over the top.
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| Paper clay blade halves |
Pouring over the top was a bad idea, while this is what the instructions recommended, the paper clay is too light and floated within the silicon rubber. I should have pressed the knife halves into the top of the molding material so they didn't float. Due to this mistake, the molds were very deep, and far deeper than the blade needed to be.
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| Knife mold |
Once the mold was complete, I made a big batch of resin and cast the two halves. Once they were set, I then used a small batch of resin to stick the two halves together. You can see how the edges dont quite match on the two molds in the image below. You can also see how dull the surface turned out due to the roughness of the paper clay.
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| raw knife cast |
To clean up the surface, I first used a Dremel and a belt sander to grind the edges even and clean up any odd cuts or bumps. Then to give the blade a shiny finish, I added a fresh coat of clear resin to the entire blade. To do so without having to lay the blade down, I hung the blade to allow both sides to be covered at once. I did not have anything fancy to hand the blade with, so I used a cheap clamp, some string and stick from my yard. The stick was then stuck on the shelves in my front sun-room. It actually took several layers of resin, with 24hr dry time in between to the finish I wanted.
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| Shiny finished blade |
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| Hanging blade with resin and LED |
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I also added an LED into the blade at the top. To set in the LED, I drilled into the blade where it would meet the handle. The hole was drilled slightly larger than the blade and then I used resin to bond the LED to the blade (the wires are sticking out of the top of the blade in the hanging picture). Unfortunately, I accidentally used blue pigment instead of dye so the blade is not clear enough for the LED to have much effect.
The remainder of the parts were a gear from a bike, a couple of pipe fittings and a big copper pipe.
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| Knife parts |
The copper pipe had two square cuts made a dremel to allow the blade to sit into the pipe and allow me to add cross lacing with leather to make the blade look tied in with leather. The pipe fittings were chosen to allow the electronics (switch, battery and wires) for the LED to be kept in the pipe but still allow easy access. The larger fitting was epoxied onto the end of the pipe and the smaller fitting can be screwed into the larger fitting allowing access to the stuff inside the pipe. To use the gear as a pommel, we needed to cut it. The dremel was actually able to cut the bike gear, although there were lots of sparks and great need for eye and skin protection. The broken gear was then glued and wired into the smaller pipe fitting.
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| knife pommel |
Finally, the I covered the pipe with some scrap leather to make holding the knife more pleasant and added the decorative lacing that 'holds' the blade in place. In actuality the blade is epoxied in place.
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| Leather handle cover and lacing |
Other than using pigment instead of dye, which caused the LED to be less functional than I would like, I am pleased with the knife overall and certainly learned a lot!
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| Completed knife |
