VDI Thread

In 1876 Karl Deliste suggested this thread and it was accepted by the VDI (Verein Deutscher Ingenieure) in Breslau 1888. However, this thread was replaced by the S.I.-Thread on the International Congress named "Internationaler Kongress zur Vereinheitlichung der Gewinde" which took place on 3rd and 4th October 1898 and is no longer used.
The flank angle is 53° 8'.

Major Diameter
mm
Pitch
mm
Tapping
Drill Size
mm
Wrench Size
mm
6.00 1.00 4.50 11
7.00 1.10 5.35 14
8.00 1.20 6.20 14
9.00 1.30 7.05 18
10.00 1.40 7.90 18
12.00 1.60 9.60 22
14.00 1.80 11.30 25
16.00 2.00 13.00 28
18.00 2.20 14.70 31
20.00 2.40 16.40 34
22.00 2.80 17.80 37
24.00 2.80 19.80 40
26.00 3.20 21.20 43
28.00 3.20 23.20 46
30.00 3.60 24.60 49
32.00 3.60 26.60 52
36.00 4.00 30.00 58
40.00 4.40 33.40 64