Sitemap
Every page on the site, grouped by type.
Main
Guides
- How to tap a hole by hand
- How to calculate tap drill size
- Thread percentage explained: why 75%
- Blind holes: how deep to drill before tapping
- Taper, plug and bottoming taps (and spiral point vs spiral flute)
- Number, letter, fractional and metric drill sizes explained
- Clearance holes: close, normal and loose fit
- Thread forming taps: what drill size to use
- How to remove a broken tap
- Pilot holes for wood screws: how to size them
- Lag screw pilot holes: the two-hole method
- UNC vs UNF, and how to read a thread callout
Charts
Inch threads
- #0-80
- #1-64
- #1-72
- #2-56
- #2-64
- #3-48
- #3-56
- #4-40
- #4-48
- #5-40
- #5-44
- #6-32
- #6-40
- #8-32
- #8-36
- #10-24
- #10-32
- #12-24
- #12-28
- #12-32
- 1/4-20
- 1/4-28
- 1/4-32
- 5/16-18
- 5/16-24
- 5/16-32
- 3/8-16
- 3/8-24
- 3/8-32
- 7/16-14
- 7/16-20
- 7/16-28
- 1/2-13
- 1/2-20
- 1/2-28
- 9/16-12
- 9/16-18
- 5/8-11
- 5/8-18
- 3/4-10
- 3/4-16
- 7/8-9
- 7/8-14
- 1-8
- 1-12
- 1-1/8-7
- 1-1/8-12
- 1-1/4-7
- 1-1/4-12
- 1-3/8-6
- 1-3/8-12
- 1-1/2-6
- 1-1/2-12