Page 235 - Fanar

Technical Information i

4.3. Types of machine tap chamfers

Chamfer length presented in
Symbol Sketch Angle
the quantity of the thread coils Sketch
6÷8 P
κ
A 6 ÷ 8 P 5°

3,5÷5 P
κ
B 3,5 ÷ 5,5 P 8°

2÷3 P
κ
C 2 ÷ 3 P 17°

3,5÷5,5 P
κ
D 3,5 ÷ 5 P 8°

1,5÷2 P
κ
E 1,5 ÷ 2 P 23°

1P
κ
F 1 P 35°

4.4. Types of Machine Tap Chip Flutes

Straight Flutes

In combination with the chamfer A or D applied for the through holes and with the chamfer E or F for the blind
holes. Tap with the chamfer C can be used for both types of holes.

It is recommended for materials giving a short chip. The grooves evacuate only some of the chips, which
slowly move along the axis. The tap should not be used for deep blind holes or materials giving a long chip.
The length of threads, which can be made - up to ca 1.5xD

11

231