What size drill bit to use for #10 wood screw?
Drill bit sizes for pre-drilling (most commonly used sizes in bold)
|Screw Size||Pilot hole size for hardwoods*||Pilot hole size for softwood**|
US Machine Screw Diameters
- Metric Imperial Screw Conversion Chart
Diameter (mm) Length (mm) Closest Imperial Size Gauge x Length 4mm 12 8 x 1/2 16 8 x 5/8 20 8 x 3/4 25 8 x 1
- The second is if you want to hide a screw head, the countersink hole will allow the head of the screw to sink below the material it is inserted into and can then be filled over and painted. To drill a countersink, place the countersink bit in your drill and push down lightly on the pilot hole.
To Tap This Size Screw Or Bolt: Use This Drill Bit: (Closest Fractional:) 4mm-0.70mm 3.4mm - 4mm-0.75mm 3.4mm - 8-32 NC #29 - 8-36 NF #29 9/64"
Wood Screw Pilot Hole Sizes
|Screw Size||Hard Wood|
|Tapered Bit||Straight Bit|
- Drill the tap hole: The size of the drill bit to be used is dependent on the type of spile you are using. Most spiles require either a 7/16 or 5/16 bit. Drill a hole 2 to 2 ½ inches deep.
- Your normal wood screws are not structural. While undoubtedly considerably stronger than normal screws, this leads me to still question their shear resistance. In the end: nails, hex bolts, and lag bolts are still better in most applications. Structural screws are just easier than bolting and cooler than nailing.
- Difference Between Nails and Screws. Since a screw has threads, you can not use a hammer, you need a screwdriver or some tool that turns the screw into the material. Hence that is why on the top of a nail, the head is flat, while the screw has a dimple for a philips, flat head or another type of tool to do the turning.
Your pilot-hole drill-bit size will depend on the size of your sheet-metal screw. A size-4 screw should have a pilot-hole drill size of 3/32 inches; size 6, 7/64 inches; size 8, 1/8 inches; size 10, 9/64 inches; size 12, 5/32 inches; size 14-1/4 inches, 3/16 inches; and 5/16 inches, 1/4 inches.
- The "8" refers to the size (diameter) of the screw, and the "32" means it has 32 threads to the inch. The diameter is measured at the shank of the screw. Screws are sized by gauge number and length. For example, an 8 gauge screw with 32 threads per inch and 1" in length would be written as: 8-32 X 1".
- Wood screw diameter can be measured either as a shank diameter or a root diameter. The measurement is then cross referenced to a size number known as a wire gauge size. Thread diameter is used when measuring sheet metal screws. The measurement is then cross referenced to a size number known as a wire gauge size.
- If you're attempting to attach sheet metal, you should choose metal screws. On the other hand, wood screws are better suited for applications involving plywood, lumber and other wood materials. Although you can use metal screws in wood, wood screws have been meticulously designed for this very purpose.
Updated: 3rd December 2019