48 —
M
achinist
c
alc™
P
ro
(cont’d)
t
(Min. Internal Major Diameter)
MAJR-
SIZe
5.0000
MM
5. Switch to External 4g Tolerance Class and find the available
External Thread characteristics:
g b b
(Thread Class)
eXT
MM
4G
t
THReD
SIZe
$
5. – 0.75
MM
t
(Rod Size for Thread Cutting)
ROD
SIZe
5.0000
MM
t
(Rod Size for Cold Forming)
CfORM
SIZe
4.4520
MM
t
(Max. External Pitch Diameter)
PTCH+
SIZe
4.4910
MM
t
(Min. External Pitch Diameter)
PTCH-
SIZe
4.4350
MM
t
(Max. External Major Diameter)
MAJR+
SIZe
4.9780
MM
t
(Min. External Major Diameter)
MAJR-
SIZe
4.8880
MM
t
(Max. External Minor Diameter)
MINR+
SIZe
4.1660
MM
Custom Thread Percentage
The
Machinist Calc Pro
uses a default Thread Grip Percentage
of 75% when calculating Tap Drill sizes. With the custom
Percentage Thread function, you can enter a different value to
calculate Tap Drill sizes.
Calculate the Tap Drill Size for a 1/4-26 screw, then change
the Thread Grip Percentage to 50% and calculate the new
Tap Drill Size.
KeySTROKe
DISPLAy
g *
ALL CLeARed
1. Enter the Thread Size and calculate the Cut Tap and Roll Tap
Drill Sizes:
1 / 4 t
SIZe
1/4 –
INCH
2 6 t
THReD
SIZe
$
1/4 –
26
INCH
t
(Cut Tap Drill Size)
TAP
DRILL SIZe
3
t
* (Roll Tap Drill Size)
R-TAP
DRILL SIZe
5.9
MM
KeySTROKe
DISPLAy