What Is a Screw Gauge
- Lee L & J Home Ltd
- Jun 4
- 1 min read
Updated: Jun 9
Screw gauge refers to the diameter of the shank on a screw. It's measured using an imperial system that ranks the size with a number from 1 to 20. The higher the gauge, the bigger the screw.
The table below shows how imperial gauge sizes relate to metric screw sizes and gives the clearance and pilot hole sizes needed for each gauge size:
GAUGE | CLEARANCE HOLE | PILOT HOLE | |
Imperial | Metric |
|
|
2 | 2mm | 2.5mm | 1.6mm |
3 | 2.5mm | 3mm | 1.6mm |
4 | 3mm | 3.5mm | 2mm |
6 | 3.5mm | 4mm | 2mm |
8 | 4mm | 5mm | 2.5mm |
10 | 5mm | 5.75mm | 3.5mm |
12 | 5.5mm | 6.5mm | 3.5mm |
14 | 6.5mm | 6.5mm | 4mm |
Comments