Check your screw size (metric or inch)
2. Choose a corresponding drill tap by using the Easy-understanding Drill Tap Chart.
3. Clamp your work if it’s not secured tightly.
4. Insert the drill tap into your impact driver and turn the chuck tightly.
5. Apply some cutting liquid or lubricant to the drill tap.
6. Place the drill tap split point in the targeted position vertically.
7. Push your impact driver with appropriate pressure at a slow RPM rate.
8. Drilling sequence: drilling, tapping, and chamfering.
9. You can add some cutting fluid to the work piece during the drilling process.
10. When finishing chamfering, push the reverse button to back out the drill tap.