1. To make this rivet head punch, you’ll need some steel rod (I modified a 1/8-inch pin punch from a hardware store set), some ball burs for steel, a scribe, bur lubricant, dividers, abrasives and polishing compound, and a flex-shaft. It’s also helpful to have a circle template.

2. Measure your steel rod and set the dividers at that diameter. This punch is 1/8-inch, but any diameter steel rod that’s near your rivet head size will work.

3. Mark the center point of the rod. A circle template makes this an easy task because the openings have crosshairs.

4. For the final cut size, choose a ball bur that is slightly less than the diameter of your rod measurement. Then, choose two ball burs that are smaller in diameter than the final one. You want a graduated series from final down to smallest.

5. Start with the smallest bur. Lubricate it well. Create a shallow divot at the center point of the rod. Switch to the middle-sized bur, lubricate it well, and enlarge the divot. Cut slowly to avoid dulling the bur by overheating it.

6. Finally, switch to the final bur size and focus on creating a clean and smooth bowl-shaped hemisphere in the end of the rod, inspecting it often for accuracy.

7. Use flexible abrasive wheels and points to sand smooth the entire modified tip of the punch and to remove any bur marks or imperfections in the steel.

8. After that, use a steel wire cup bur to burnish the metal smooth.

9. Polish the steel with Fabulustre polishing compound on a hard felt bob or whatever you use for steel. Your aim is to give the metal a mirror finish.

10. To use the punch, install the rivet as normal and cross peen the wire to expand/upset the metal. Then position the rivet punch over the rivet head and gently tap the punch with a hammer to planish out any ruts and smooth the wire end into a ball. As you tap, change the position of the end of the punch by simultaneously arcing it back and forth to evenly smooth the metal within the hemispherical tip.