What size bolt fits in a 1/4 hole?

Asked By: Abdelwahid Panera | Last Updated: 10th March, 2020
Category: hobbies and interests woodworking
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For example, a 1/4-inch-diameter bolt with 20 threads per inch is designated as a 1/4-20 bolt.

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Moreover, what size bolt fits in a 1/2 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.

Subsequently, question is, how big a pilot hole should I drill? First, drill a pilot hole through both boards. Pilot holes guarantee that your screw won't break off and your wood won't crack. For most hardwoods, the pilot hole should be at least as large as the screw's minor diameter. If the screw has deep threads, or the wood is very hard, the pilot hole should be another 1/64-in.

Beside this, what size bolt fits a 9/16 hole?

To Tap This Size Screw Or Bolt: Use This Drill Bit: (Closest Fractional:)
9/16-18 NF 33/64" 33/64"
5/8-11 NC 17/32" 17/32"
16mm-2.00mm 14.2mm 35/64"
5/8-18 NF 37/64" 37/64"

What size screw fits a 3/16 hole?

Wood Screw Pilot Hole Sizes

Screw Size Hard Wood
Tapered Bit Straight Bit
#9 3/16" 9/64"
#10 13/64" 9/64"
#12 7/32" 5/32"

37 Related Question Answers Found

What size bolt fits in a 1/4 hole?

For example, a 1/4-inch-diameter bolt with 20 threads per inch is designated as a 1/4-20 bolt.

Is a #8 or #10 screw bigger?

Machine screws are often found in sizes of: 0, 1, 2, 3, 4, 5, 6, 8, 10, 12, 14—the larger the number, the larger the screw.

What size bolt has 1 7 8 head?

US Bolt Head/Wrench Size
Bolt Diameter Head and Wrench Size
Hex Bolt - Lag Bolt - Square Bolt Heavy Hex Bolt
5/8" 15/16" 1-1/16"
3/4" 1-1/8" 1-1/4"
7/8" 1-5/16" 1-7/16"

What size is a #10 bolt?

US Machine Screw Diameters
Size Thread Diameter
Decimal Nearest Fractional
#6 0.13" 9/64"
#8 0.16" 5/32"
#10 0.19" 3/16"

What size drill bit should I use?


Use a bit 1/64” smaller than the target hole size for softwoods. Use a bit exactly the same size as the hole when working on other materials. If you're not sure which to select, choose a drill bit 1/64” larger than the hole you wish to create.

How do I measure screw size?

Length is measured from the point at which the head sits flat with the surface, to the tip of the threads. Hex, pan, truss, button, socket cap, and round head screws are measured from right under the head to the end of the threads. Flat head screws are measured from the top of the head to the tip of the threads.

What size hole should I drill for a 3/8 bolt?

Target and Range
Most drill charts recommend a 5/16 drill for a 3/8-16 bolt.

What size drill bit to pre drill for a #10 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**
#9 1/8 3/32
#10 1/8 7/64
#11 5/32 9/64
#12 9/64 1/8

What size hole do you drill for a 1/4 Tapcon?

The Tapcon drill bit that is used depends on the diameter of the Tapcon screw being installed. The 3/16” Tapcon requires the use of 5/32” diameter bit, and the 1/4Tapcon requires a 3/16” diameter bit.

What size drill bit do I need for a 1/4 20 tap?


US Tap and Drill Bit Size Table
Tap Fractional Drill Bit Number Drill Bit
#12-24 11/64" 16
1/4"-20 13/64" 7
1/4"-28 7/32" 3
5/16"-18 17/64" -

What size drill bit do I use for a 5/16 tap?

OBW0549. Looking at the "Tap Drill Chart" section at the bottom, they recommend an "F" drill for a 5/16"-18 fastener. Then, looking up above at the "Decimal Equivalent Chart" section, an "F" drill measures 0.257", about halfway between 1/4" and 17/64".

What is the clearance hole drill size for #4 40 fasteners?

Tap and Clearance Drill Sizes
Screw O.D.
3-48 0.099 0.1040
4-40 0.1120 0.1160
5-40 0.125 0.1360
6-32 0.1380 0.1440

How big is a #6 screw?

Screws have three basic measurements: gauge, threads per inch, and shaft length in inches. So, you may also see a measurement like 6-32 x 1 1/2". This means it's a #6 diameter, with 32 threads per inch (almost double the normal thread count as a standard wood screw) and an inch and a half long.

What's the next size up from 13 16?

Wrench Size Chart for Bolts
Bolt Diameter Wrench Size (Standard) Wrench Size (Metric)
9/16" 13/16" 21mm
5/8" 15/16" 24mm
3/4" 1-1/8" 29mm
7/8" 1-5/16" 34mm

What size is a 7 drill bit?


#7 is a 0.201" diameter bit, 13/64" is 0.203" diameter.

How do you measure bolt socket size?

Multiply the first number which is the bolt size in inches or millimeters, by 1.5 using a pocket calculator, if necessary. For example, for the numbers in Step 1, 1/2 x 1.5 = . 75 or 3/4, which is the wrench size needed for this standard-sized bolt.

Do self drilling screws need pilot holes?

Basically a self drilling screw is a tapping screw that doesn't need a pilot hole. They both technically tap their own threads, all screws do this to varying degrees. But, the self drilling screws skip a step in the process.