Position the sink upright on a stable work area.
Locate the partially drilled knockout holes made by the manufacturer. Some manufacturers place stickers over the knockout sections.
Position your chisel, screwdriver or metal punch over the center of the partially drilled knockout holes. Strike the chisel, screwdriver or metal punch firmly with the hammer.
Repeat Step 3 for any additional faucet holes.
Raze any rough spots smooth with a file.
Things You Will Need
- Chisel, screwdriver or metal punch
- Enlist a helper to hold the sink steady while you hammer the knockouts.