After you’ve made your alternating half circle cuts down both sides, it’s time to move on to the triangle file. Using the same 45 and 90 angle as you made your first cuts, make a SMALL (only two or three strokse) cut with the triangle file just past each half-circle cut, toward the tip of the knife. This step isn’t pictured, but is essential in helping you get nice, sharp, uniformly placed thorns. After you’ve made a SMALL cut, shift your file angle to a compound 45 degree angle to make the thorns. The file now runs at a 45 degree angle to the flat of the blade (same as the previous cuts) and also at a 45 degree angle to the spine. Use this compound angle to set your thorns. The small cuts you made in the previous step will serve to keep all of your thorn cuts in the same place relative to the half-circles. What you’ll end up with should look like the picture above.
