Blog

Your Source for Automatic Drills, Multiple Spindle Heads, and more

UNC UNF TPI chart

UNC UNF TPIchart.pdf

Bolt Size    No. or Inches

Threads Per Inch (TPI)

Coarse  Thread UNC

Fine Thread  UNF

#0 80
#1 64 72
#2 56 64
#3 48 56
#4 40 48
#5 40 44
#6 32 40
#8 32 36
#10 24 32
#12 24 28
1/4 20 28
5/16 18 24
3/8 16 24
7/16 14 20
1/2 13 20
9/16 12 18
5/8 11 18
3/4 10 16
7/8 9 14
1 8 12
1-1/8 7 12
1-1/4 7 12
1-3/8 6 12
1-1/2 6 12
1-3/4 5
2 4-1/2
2-1/4 4-1/2
2-1/2 4
2-3/4 4
3 4
3-1/4 4
3-1/2 4
3-3/4 4
4 4

Leave a Reply

Are You Human? *

What is 10 + 8 ?
Please leave these two fields as-is:
IMPORTANT! To control spam, please answer the math problem. AutoDrill Staff