Page 47 - notch_grip_2021

USER GUIDE

Threading Limits with Standard NOTCH-GRIP Inserts

The following charts list the largest pitch that can be applied on internal applications for
Acme and V-Threading NOTCH-GRIP inserts in sizes 2,3, 4 and 6.

60˚ V-Threading Limits Acme Threading Limits

FLT-2 Inserts Internal Threading Limitations FLA-2 Internal Threading Limitations
Minimum
Minimum
Threads Nominal Minor Diameter Threads Nominal Minor Diameter
per Inch Thread Size Inch MM
per Inch Thread Size Inch MM 2.333 59.26
6 1-7/8 1.695 43.05 6 2-1/2 2.125 53.98
7 1-3/4 1.595 40.51 8 2-1/4 1.900 48.26
8 1-5/8 1.490 37.85 10 1.667 42.34
9 1-9/16 1.442 36.63 12 2 1.554 39.47
10 1-1/2 1.392 35.36 14 1-3/4 1.438 36.53
11 1-7/16 1.339 34.01 16* 1-5/8
12 1-3/8 1.285 32.64 1-1/2

* 16 pitch acme threads and finer can be cut provided the minor

13 1-5/16 1.229 31.22 diameter is 1.438 or larger.

14 1-1/4 1.173 29.79
16 1-1/4 1.182 30.02
18 1-1/8 1.065 27.05
20 1-1/8 1.071 27.20
24 1-1/16 1.017 25.83

* 24 TPI and finer can be cut with a #2 series insert provided that

the minor diameter is 1.000 or larger.

minor diameter major diameter A secondary clearance can be ground
(minimum bore) (nominal thread size) on the leading edge of the form of the
insert to provide sufficient helical clear
ance for machining courser threads and
multiple start threads.
Modified standard inserts may be produced for
special threads or ones not listed on the charts
shown. Quoted upon request.

FLA-3, 4 & 6 Internal Threading Limitations

threads Minimum
per inch
Threads Nominal Minor Diameter

FLT-3 & 4 Inserts Internal Threading Limitations per Inch Thread Size Inch MM
2* 5 4.500 114.30
Minimum 4.100 104.14
2-1/2** 4-1/2 3.665 93.09
Threads Nominal Minor Diameter 3** 4 3.250 82.55
4 2.800 71.12
per Inch Thread Size Inch MM 5 3-1/2 2.333 59.26
4** 3 2.729 69.32 6 3 2.125 23.98
4-1/2** 2-7/8 2.634 66.90 8 1.900 48.26
5 2-3/4 2.534 64.36 10 2-1/2 1.667 42.34
6 2-1/2 2.320 58.93 12 2-1/4 1.554 39.47
7 2-1/4 2.095 53.21 14 1.438 36.53
8 2 1.865 47.37 16* 2
9 1-15/16 1.817 46.15 1-3/4
10 1-7/8 1.767 44.88 1-5/8
1-1/2

11 1-13/16 1.714 43.54 * 16 pitch acme threads and finer can be cut provided the minor

12 1-3/4 1.660 42.16 diameter is 1.438 or larger.

13 1-5/8 1.542 39.17 ** FLA-6 only.

14 1-9/16 1.485 37.72 NOTE: Positive rake ACME inserts are recommended for

16* 1-7/16 1.370 34.80 stainless steels and high-temp alloy appl cations.

Quoted upon request.

* 16 pitch acme threads and finer can be cut provided the minor

diameter is 1.370 or larger.

** FLT-4 only.

90˚

3˚

back clearance

NOTE: Tool holders are designed to locate the insert at
a 3˚ angle to provide back clearance down the side.

FLTB-2A & 2B Internal Threading Limitations FLTB-3A & 4A Internal Threading Limitations FLTB-3B & 4B Internal Threading Limitations
Minimum
Threads Nominal Minimum Threads Nominal Minimum Threads Nominal Minor Diameter
per Inch Thread Minor Diameter per Inch Thread Size Minor Diameter per Inch Thread Size
Inch MM Inch MM
8 Size Inch MM 4 *2-7/8 2.575 65.41
10 1-3/4 1.600 40.64 4* 2-1/2 2.200 55.88 5 2-3/4 2.510 63.75
12 1-5/8 1.505 38.23 5 2-1/4 2.010 51.05 6 2-3/8 1.175 29.85
16 1-1/2 1.400 35.56 6 2 1.800 45.72 8 2-1/8 1.975 50.17
20 1-1/4 1.175 29.85 8 1-3/4 1.600 40.64 10 1-7/8 1.755 44.58
1-1/16 1.002 25.45 10 1-5/8 1.505 38.23 12 1-5/8 1.525 38.74
16 1-1/2 1.407 35.74
12** 1-1/2 1.400 35.56 20 1-7/16 1.378 35.00

* FLTB-4A insert only * FLTB-4B insert only

** 16 or 20 threads per inch can be cut

providing minor diameter is 1.375 or larger. 47