- 1). Clean an old saw blade thoroughly, grinding away rust with a belt sander or a grinder.
- 2). Cut out a cardboard pattern from dimensions you're planning to form your arrowhead, using scissors. Use the cardboard pattern as a guide and trace around its edges with a marker directly onto the saw blade. The pattern can also be drawn on the saw blade slightly larger than the dimensions you would like; this will make up for steel that will have to be sanded down.
- 3). Cut the arrowhead pattern out of the saw blade by using either a cutting torch or a high-powered Dremel tool. Grind any rough edges or torch marks off by using coarse sandpaper on a sanding belt or a grinder. Use a pair of pliers to hold the arrowhead as it is likely quite small and grinders have been known to injure fingers if they get caught.
- 4). Grind/sharpen the edges of your arrowhead, using a grinder. Run the arrowhead across the grinder in a steady, consistent motion to form the edge. Continue this process with finer sandpaper to make the arrowhead consistently smooth throughout its body.
- 5). Heat-treat/harden your arrowhead to the point that it glows red and then submerge it in tempering oil. Polish off any roughened surfaces with very fine sandpaper and a metal polish.
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