We will have a grid of logos, when clicked takes you to their estore website. Metric Drills. Metric Threads Metric Fasteners Metric Gears Metrics in Clothing Metrics in the Home Metric Products. Digital Design Ltd. Site Map Bookmark & Share: Metric Threads. There are two kinds of ISO metric threads: coarse and fine. The ISO metric thread profile and proportions are as follows: Metric Thread Pitch and Tapping Sizes.
ANSI/ASME B1.1 Unified National Thread - UNC Coarse series and UNF Fine series
- UNC – Unified National Coarse Thread - comparable with the ISO metric thread
- UNF – Unified National Fine Thread
- Female and Male UNC/UNF threads are both parallel
- The UNC/UNF flank angle is 60°
Unified threads comes in three different classes:
- for applications where a liberal tolerance is required to permit easy assembly even with slightly nicked threads
- most commonly used class for general applications
- for applications where closeness of fit and/or accuracy of thread elements are important
UNC - Unified Coarse Threads
UNC threads according ANSI B1.1:
Major Diameter (in) | Threads per inch | Major Diameter (in) | Major Diameter (mm) | Tap Drill Size (mm) | Pitch (mm) |
---|---|---|---|---|---|
#1 - 64 | 64 | 0.073 | 1.854 | 1.50 | 0.397 |
#2 - 56 | 56 | 0.086 | 2.184 | 1.80 | 0.453 |
#3 - 48 | 48 | 0.099 | 2.515 | 2.10 | 0.529 |
#4 - 40 | 40 | 0.112 | 2.845 | 2.35 | 0.635 |
#5 - 40 | 40 | 0.125 | 3.175 | 2.65 | 0.635 |
#6 - 32 | 32 | 0.138 | 3.505 | 2.85 | 0.794 |
#8 - 32 | 32 | 0.164 | 4.166 | 3.50 | 0.794 |
#10 - 24 | 24 | 0.190 | 4.826 | 4.00 | 1.058 |
#12 - 24 | 24 | 0.216 | 5.486 | 4.65 | 1.058 |
1/4' - 20 | 20 | 0.250 | 6.350 | 5.35 | 1.270 |
5/16' - 18 | 18 | 0.313 | 7.938 | 6.80 | 1.411 |
3/8' - 16 | 16 | 0.375 | 9.525 | 8.25 | 1.587 |
7/16' - 14 | 14 | 0.438 | 11.112 | 9.65 | 1.814 |
1/2' - 13 | 13 | 0.500 | 12.700 | 11.15 | 1.954 |
9/16' - 12 | 12 | 0.563 | 14.288 | 12.60 | 2.117 |
5/8' - 11 | 11 | 0.625 | 15.875 | 14.05 | 2.309 |
3/4' - 10 | 10 | 0.750 | 19.050 | 17.00 | 2.540 |
7/8' - 9 | 9 | 0.875 | 22.225 | 20.00 | 2.822 |
1' - 8 | 8 | 1.000 | 25.400 | 22.85 | 3.175 |
1 1/8' - 7 | 7 | 1.125 | 28.575 | 25.65 | 3.628 |
1 1/4' - 7 | 7 | 1.250 | 31.750 | 28.85 | 3.628 |
1 3/8' - 6 | 6 | 1.375 | 43.925 | 31.55 | 4.233 |
1 1/2' - 6 | 6 | 1.500 | 38.100 | 34.70 | 4.233 |
1 3/4' - 5 | 5 | 1.750 | 44.450 | 40.40 | 5.080 |
2' - 4 1/2 | 4 1/2 | 2.000 | 50.800 | 46.30 | 5.644 |
2 1/4' - 4 1/2 | 4 1/2 | 2.250 | 57.150 | 52.65 | 5.644 |
2 1/2' - 4 | 4 | 2.500 | 63.500 | 58.50 | 6.350 |
2 3/4' - 4 | 4 | 2.750 | 69.850 | 64.75 | 6.350 |
3' - 4 | 4 | 3.000 | 76.200 | 71.10 | 6.350 |
3 1/4' - 4 | 4 | 3.250 | 82.550 | 77.45 | 6.350 |
3 1/2' - 4 | 4 | 3.500 | 88.900 | 83.80 | 6.350 |
3 3/4' - 4 | 4 | 3.750 | 95.250 | 90.15 | 6.350 |
4' - 4 | 4 | 4.000 | 101.600 | 96.50 | 6.350 |
Example - Typical designation of an UNC thread
- 1/4” x 20 UNC
UNF - Unified National Fine Threads
UNF threads ANSI B1.1:
Major Diameter (in) | Threads per inch | Major Diameter (in) | Major Diameter (mm) | Tap Drill Size (mm) | Pitch (mm) |
---|---|---|---|---|---|
#0 - 80 | 80 | 0.060 | 1.524 | 1.25 | 0.317 |
#1 - 72 | 72 | 0.073 | 1.854 | 1.55 | 0.353 |
#2 - 64 | 64 | 0.086 | 2.184 | 1.90 | 0.397 |
#3 - 56 | 56 | 0.099 | 2.515 | 2.15 | 0.453 |
#4 - 48 | 48 | 0.112 | 2.845 | 2.40 | 0.529 |
#5 - 44 | 44 | 0.125 | 3.175 | 2.70 | 0.577 |
#6 - 40 | 40 | 0.138 | 3.505 | 2.95 | 0.635 |
#8 - 36 | 36 | 0.164 | 4.166 | 3.50 | 0.705 |
#10 - 32 | 32 | 0.190 | 4.826 | 4.10 | 0.794 |
#12 - 28 | 28 | 0.216 | 5.486 | 4.70 | 0.907 |
1/4' - 28 | 28 | 0.250 | 6.350 | 5.50 | 0.907 |
5/16' - 24 | 24 | 0.313 | 7.938 | 6.90 | 1.058 |
3/8' - 24 | 24 | 0.375 | 9.525 | 8.50 | 1.058 |
7/16' - 20 | 20 | 0.438 | 11.112 | 9.90 | 1.270 |
1/2' - 20 | 20 | 0.500 | 12.700 | 11.50 | 1.270 |
9/16' - 18 | 18 | 0.563 | 14.288 | 12.90 | 1.411 |
5/8' - 18 | 18 | 0.625 | 15.875 | 14.50 | 1.411 |
3/4' - 16 | 16 | 0.750 | 19.050 | 17.50 | 1.587 |
7/8' - 14 | 14 | 0.875 | 22.225 | 20.40 | 1.814 |
1' - 12 | 12 | 1.000 | 25.400 | 23.25 | 2.117 |
1 1/8' - 12 | 12 | 1.125 | 28.575 | 26.50 | 2.117 |
1 1/4' - 12 | 12 | 1.250 | 31.750 | 29.50 | 2.117 |
1 3/8' - 12 | 12 | 1.375 | 34.925 | 32.75 | 2.117 |
1 1/2' - 12 | 12 | 1.500 | 38.100 | 36.00 | 2.117 |
Example - Typical designation of an UNF thread
- 1/2” x 20 UNF
Related Topics
- Mechanics - Forces, acceleration, displacement, vectors, motion, momentum, energy of objects and more
- Threads - Thread data - metric, unified, ACME and others
- Fasteners - Bolts, nuts and threaded rods - torque, tension and loads
Related Documents
- ANSI - American National Standards Institute - ANSI provides a forum for development of American national standards
- ANSI/ASME B1.5 - ACME Screw Threads - Acme trapezoidal threads
- ASME/ANSI B16.5 - Flanges and Bolt Dimensions Class 150 to 2500 - Diameters and bolt circles for standard ASME B16.5 flanges - 1/4 to 24 inches - Class 150 to 2500
- Bolt Stretching and Tensile Stress - Tensile stress and Hooke's Law
- BS 21 - Pressure Tight Pipe Thread Joints - BSPT - British Standard Pipe Taper threads & BSP or BSPF - British Standard Pipe Parallel (Straight) threads
- Cast Iron Flanges - Stud Reference Chart - The number, diameter and length of studs for cast iron flanges class 125 and 250
- EN 10226 - Pipe threads where pressure tight joints are made on the threads - Dimensions - Pipe threads where pressure tight joints are made on the threads - Part 1: Taper external threads and parallel internal threads
- ISO 2841 - Spark Plugs Metric Threads - Metric threads spark plugs according ISO 28741
- ISO 2901 - Metric Trapezoidal Screw Threads - Dimensions of ISO metric trapezoidal screw threads
- ISO 7 - Pipe Threads where Pressure-tight Joints are made on the Threads - Pressure-tight joints made on the pipe threads
- ISO 724 - Metric Threads - Dimensions of metric threads according ISO 724
- Lubricated Bolts and Reduced Torque - Lubrication effect on bolt tension and torque
- Metric Bolts - Head and Wrench Sizes - ANSI/SO, DIN and JIS bolts
- Metric Steel Bolts - Grades and Property Classes - Metric steel bolts, screws and studs - proof and tensile strength
- Screws - Metric vs. Inches - Metric versus Imperial equivalent screw dimensions
- Steel Bolts - ASTM Grades - ASTM steel bolts - proof and tensile strength
- Steel Bolts - SAE Grades - SAE steel bolts - grades ranging grade 1 to 8.2 - proof and tensile strength
- Surface Finishing - Lumber and surface finishing abbreviations
- Threaded Bolt Stress Area - Threaded bolts tensile stress area
- US Bolts - Head and Wrench Sizes - Hex Bolt, Lag Bolt, Square Bolt and Heavy Hex Bolt
- US Bolts - Tightening Torques - Recommended bolt torques
- US Hex Bolts - Inches - ANSI/ASME B18.2.1 Dimensions of Hex Bolts - Imperial units
- US Hex Bolts - Metric - ANSI/ASME B18.2.3M Dimensions of Hex Bolts - Metric units
- US Machine Screws - Dimensions - Machine screw diameters
- US Wood Screws - Nominal Sizes - Wood screws - nominal sizes vs. diameters
- Whitworth Pipe Threads - BSPP (G) - British Standard Pipe Parallel and BSPT (R/Rp) – British Standard Tapered Pipe for pipes and tapered threads - G/R/Rp
- Wood Screws - Withdrawal Forces - Allowable withdrawal load force
- Wrench Spanner - Inches to mm - SAE to metric wrench and spanner converter chart
Tag Search
- en: unified screw threads unc unf coarse series
ANSI/ASME B1.1 Unified National Thread - UNC Coarse series and UNF Fine series
- UNC – Unified National Coarse Thread - comparable with the ISO metric thread
- UNF – Unified National Fine Thread
- Female and Male UNC/UNF threads are both parallel
- The UNC/UNF flank angle is 60°
Unified threads comes in three different classes:
- for applications where a liberal tolerance is required to permit easy assembly even with slightly nicked threads
- most commonly used class for general applications
- for applications where closeness of fit and/or accuracy of thread elements are important
UNC - Unified Coarse Threads
UNC threads according ANSI B1.1:
Major Diameter (in) | Threads per inch | Major Diameter (in) | Major Diameter (mm) | Tap Drill Size (mm) | Pitch (mm) |
---|---|---|---|---|---|
#1 - 64 | 64 | 0.073 | 1.854 | 1.50 | 0.397 |
#2 - 56 | 56 | 0.086 | 2.184 | 1.80 | 0.453 |
#3 - 48 | 48 | 0.099 | 2.515 | 2.10 | 0.529 |
#4 - 40 | 40 | 0.112 | 2.845 | 2.35 | 0.635 |
#5 - 40 | 40 | 0.125 | 3.175 | 2.65 | 0.635 |
#6 - 32 | 32 | 0.138 | 3.505 | 2.85 | 0.794 |
#8 - 32 | 32 | 0.164 | 4.166 | 3.50 | 0.794 |
#10 - 24 | 24 | 0.190 | 4.826 | 4.00 | 1.058 |
#12 - 24 | 24 | 0.216 | 5.486 | 4.65 | 1.058 |
1/4' - 20 | 20 | 0.250 | 6.350 | 5.35 | 1.270 |
5/16' - 18 | 18 | 0.313 | 7.938 | 6.80 | 1.411 |
3/8' - 16 | 16 | 0.375 | 9.525 | 8.25 | 1.587 |
7/16' - 14 | 14 | 0.438 | 11.112 | 9.65 | 1.814 |
1/2' - 13 | 13 | 0.500 | 12.700 | 11.15 | 1.954 |
9/16' - 12 | 12 | 0.563 | 14.288 | 12.60 | 2.117 |
5/8' - 11 | 11 | 0.625 | 15.875 | 14.05 | 2.309 |
3/4' - 10 | 10 | 0.750 | 19.050 | 17.00 | 2.540 |
7/8' - 9 | 9 | 0.875 | 22.225 | 20.00 | 2.822 |
1' - 8 | 8 | 1.000 | 25.400 | 22.85 | 3.175 |
1 1/8' - 7 | 7 | 1.125 | 28.575 | 25.65 | 3.628 |
1 1/4' - 7 | 7 | 1.250 | 31.750 | 28.85 | 3.628 |
1 3/8' - 6 | 6 | 1.375 | 43.925 | 31.55 | 4.233 |
1 1/2' - 6 | 6 | 1.500 | 38.100 | 34.70 | 4.233 |
1 3/4' - 5 | 5 | 1.750 | 44.450 | 40.40 | 5.080 |
2' - 4 1/2 | 4 1/2 | 2.000 | 50.800 | 46.30 | 5.644 |
2 1/4' - 4 1/2 | 4 1/2 | 2.250 | 57.150 | 52.65 | 5.644 |
2 1/2' - 4 | 4 | 2.500 | 63.500 | 58.50 | 6.350 |
2 3/4' - 4 | 4 | 2.750 | 69.850 | 64.75 | 6.350 |
3' - 4 | 4 | 3.000 | 76.200 | 71.10 | 6.350 |
3 1/4' - 4 | 4 | 3.250 | 82.550 | 77.45 | 6.350 |
3 1/2' - 4 | 4 | 3.500 | 88.900 | 83.80 | 6.350 |
3 3/4' - 4 | 4 | 3.750 | 95.250 | 90.15 | 6.350 |
4' - 4 | 4 | 4.000 | 101.600 | 96.50 | 6.350 |
Example - Typical designation of an UNC thread
- 1/4” x 20 UNC
UNF - Unified National Fine Threads
UNF threads ANSI B1.1:
Major Diameter (in) | Threads per inch | Major Diameter (in) | Major Diameter (mm) | Tap Drill Size (mm) | Pitch (mm) |
---|---|---|---|---|---|
#0 - 80 | 80 | 0.060 | 1.524 | 1.25 | 0.317 |
#1 - 72 | 72 | 0.073 | 1.854 | 1.55 | 0.353 |
#2 - 64 | 64 | 0.086 | 2.184 | 1.90 | 0.397 |
#3 - 56 | 56 | 0.099 | 2.515 | 2.15 | 0.453 |
#4 - 48 | 48 | 0.112 | 2.845 | 2.40 | 0.529 |
#5 - 44 | 44 | 0.125 | 3.175 | 2.70 | 0.577 |
#6 - 40 | 40 | 0.138 | 3.505 | 2.95 | 0.635 |
#8 - 36 | 36 | 0.164 | 4.166 | 3.50 | 0.705 |
#10 - 32 | 32 | 0.190 | 4.826 | 4.10 | 0.794 |
#12 - 28 | 28 | 0.216 | 5.486 | 4.70 | 0.907 |
1/4' - 28 | 28 | 0.250 | 6.350 | 5.50 | 0.907 |
5/16' - 24 | 24 | 0.313 | 7.938 | 6.90 | 1.058 |
3/8' - 24 | 24 | 0.375 | 9.525 | 8.50 | 1.058 |
7/16' - 20 | 20 | 0.438 | 11.112 | 9.90 | 1.270 |
1/2' - 20 | 20 | 0.500 | 12.700 | 11.50 | 1.270 |
9/16' - 18 | 18 | 0.563 | 14.288 | 12.90 | 1.411 |
5/8' - 18 | 18 | 0.625 | 15.875 | 14.50 | 1.411 |
3/4' - 16 | 16 | 0.750 | 19.050 | 17.50 | 1.587 |
7/8' - 14 | 14 | 0.875 | 22.225 | 20.40 | 1.814 |
1' - 12 | 12 | 1.000 | 25.400 | 23.25 | 2.117 |
1 1/8' - 12 | 12 | 1.125 | 28.575 | 26.50 | 2.117 |
1 1/4' - 12 | 12 | 1.250 | 31.750 | 29.50 | 2.117 |
1 3/8' - 12 | 12 | 1.375 | 34.925 | 32.75 | 2.117 |
1 1/2' - 12 | 12 | 1.500 | 38.100 | 36.00 | 2.117 |
Example - Typical designation of an UNF thread
- 1/2” x 20 UNF
Related Topics
- Mechanics - Forces, acceleration, displacement, vectors, motion, momentum, energy of objects and more
- Threads - Thread data - metric, unified, ACME and others
- Fasteners - Bolts, nuts and threaded rods - torque, tension and loads
Related Documents
- ANSI - American National Standards Institute - ANSI provides a forum for development of American national standards
- ANSI/ASME B1.5 - ACME Screw Threads - Acme trapezoidal threads
- ASME/ANSI B16.5 - Flanges and Bolt Dimensions Class 150 to 2500 - Diameters and bolt circles for standard ASME B16.5 flanges - 1/4 to 24 inches - Class 150 to 2500
- Bolt Stretching and Tensile Stress - Tensile stress and Hooke's Law
- BS 21 - Pressure Tight Pipe Thread Joints - BSPT - British Standard Pipe Taper threads & BSP or BSPF - British Standard Pipe Parallel (Straight) threads
- Cast Iron Flanges - Stud Reference Chart - The number, diameter and length of studs for cast iron flanges class 125 and 250
- EN 10226 - Pipe threads where pressure tight joints are made on the threads - Dimensions - Pipe threads where pressure tight joints are made on the threads - Part 1: Taper external threads and parallel internal threads
- ISO 2841 - Spark Plugs Metric Threads - Metric threads spark plugs according ISO 28741
- ISO 2901 - Metric Trapezoidal Screw Threads - Dimensions of ISO metric trapezoidal screw threads
- ISO 7 - Pipe Threads where Pressure-tight Joints are made on the Threads - Pressure-tight joints made on the pipe threads
- ISO 724 - Metric Threads - Dimensions of metric threads according ISO 724
- Lubricated Bolts and Reduced Torque - Lubrication effect on bolt tension and torque
- Metric Bolts - Head and Wrench Sizes - ANSI/SO, DIN and JIS bolts
- Metric Steel Bolts - Grades and Property Classes - Metric steel bolts, screws and studs - proof and tensile strength
- Screws - Metric vs. Inches - Metric versus Imperial equivalent screw dimensions
- Steel Bolts - ASTM Grades - ASTM steel bolts - proof and tensile strength
- Steel Bolts - SAE Grades - SAE steel bolts - grades ranging grade 1 to 8.2 - proof and tensile strength
- Surface Finishing - Lumber and surface finishing abbreviations
- Threaded Bolt Stress Area - Threaded bolts tensile stress area
- US Bolts - Head and Wrench Sizes - Hex Bolt, Lag Bolt, Square Bolt and Heavy Hex Bolt
- US Bolts - Tightening Torques - Recommended bolt torques
- US Hex Bolts - Inches - ANSI/ASME B18.2.1 Dimensions of Hex Bolts - Imperial units
- US Hex Bolts - Metric - ANSI/ASME B18.2.3M Dimensions of Hex Bolts - Metric units
- US Machine Screws - Dimensions - Machine screw diameters
- US Wood Screws - Nominal Sizes - Wood screws - nominal sizes vs. diameters
- Whitworth Pipe Threads - BSPP (G) - British Standard Pipe Parallel and BSPT (R/Rp) – British Standard Tapered Pipe for pipes and tapered threads - G/R/Rp
- Wood Screws - Withdrawal Forces - Allowable withdrawal load force
- Wrench Spanner - Inches to mm - SAE to metric wrench and spanner converter chart
Tag Search
- en: unified screw threads unc unf coarse series