Do you drill a hole the same size as the bolt?
If you are creating a pilot hole for a screw, the drill bit should be the same size as the body of the screw—not including the threads.
What size hole do you drill for a 1/2 lag bolt?
Lag Screw Pilot Hole Diameters
| Nominal Diameter of Lag Bolt, inches | Shank (Unthreaded) Portion, inches | Diameter of Pilot Hole, inches (Thread Portion) |
|---|---|---|
| 1⁄2 | 1⁄2 | 5⁄16 |
| 9⁄16 | 9⁄16 | 23⁄64 |
| 5⁄8 | 5⁄8 | 13⁄32 |
| 3⁄4 | 3⁄4 | 1⁄2 |
What size bolt fits in a 1/2 inch hole?
For holes under 1/2 inch, drill a clearance hole that is 1/64 larger. For holes larger then 1/2, drill clearance hole 1/32 larger. You should never be drilling the same dia clearance hole as the screw size. No to 3/8 hole for 3/8 screw.
What size hole should I drill for a 1/2 bolt?
| Screw Size-TPI | Recommended Hole Diameter | Drill Bit Size |
|---|---|---|
| 1/4-20 | 0.2280″ | #1 |
| 5/16-18 | 0.2900″ | L |
| 3/8-16 | 0.3580″ | T |
| 1/2-13 | 0.4531″ | 29/64″ |
How are carriage bolts measured?
Carriage bolt lengths are measured from under the head, not from under the square neck.
What kind of drill bit do you use for carriage bolts?
Use the same size drill bit as the diameter of the bolt. If you are using a 1/2″ diameter bolt use a 1/2″ drill bit. Carriage bolts are very misunderstood and yet very simple to install. Made primarily for wood, carriage bolts have a square shoulder right below the head.
How big of a carriage bolt do I Need?
What size carriage bolt do I need? Typically, carriage bolt sizes range from #10 to 3/4″ in diameter while lengths span from about 1/2″ to 20″—only larger sizes are available in long lengths. Measure length from under the head to the threaded end of the bolt.
What kind of steel is a carriage bolt made of?
Carriage bolt made from medium carbon alloy steel and heat-treated. Greater load carrying capacity compared to a low carbon carriage bolt. Greater load carrying capacity compared to a Grade-5 carriage bolt.
Where is the shoulder on a carriage bolt?
Made primarily for wood, carriage bolts have a square shoulder right below the head. This shoulder is designed to catch on wood and be pulled into it (by tightening the nut).