+1 on tinkerer's points.
From a lot of experience, I will tell you that you need to cut the basic blank and slot it first. Don't do that until after HT. Once the basic guard blank is done, the slot is centered, and the profile is right, add the gear look.
For an 8-fold symmetry guard:
Mark a line from the top to the bottom ( 12:00 and 6:00) on the vertical axis through the tang slot
Mark the side axis line ( 3:00 and 9:00) at 90 degrees to the slot.
Mark the spots between these for the other gear teeth.
Saw/grind a small slot on each mark down the center. You can cut diagonal cuts to make a rough tooth.
Use a square file to cut in the final shapes.
Do each tooth part-way, and slowly define all of them as a group- NEVER do one then the next!!!!
Leave some room for fine filing, sanding, and buffing.
The guard can be darkened in FC or Parkerized.