G49 - G64_G49 - G64 3/5/14 2:27 PM Page G-50
Miter Gears
20° Pressure Angle
Miter Gears are ordinarily used as right angle drives, transmitting horsepower between intersecting shafts at a 1:1 ratio. They
are used where high efficiency is required. Only miters of the
same number of teeth, pitch, and pressure angle can be operated together. More than two miters may be used in sets, as in a
differential.
The mounting distance must be held in order to maintain proper
backlash between gears. This will also insure that the ends of
the gear teeth will be flush with each other. The use of a straight
mineral oil as a lubricant is recommended for most Miter Gear
applications.
The thrust of Miter Gears causes the gears to separate; therefore, ball bearings or roller bearings should be used rather than
sleeve bearings. Provisions should be made using thrust bearings to absorb backward thrust.
steel.
Martin Stock Miter Gears are manufactured from .40 carbon
All standard stock Miter Gears must be mounted at right angles
(90 degrees) for proper tooth bearing.
All Martin Miter and Bevel Gears are generated with the
Coniflex tooth form. A slight misalignment of gears is permissible because of the localized tooth bearing running lengthwise
along the gear tooth.
G-50
The “M” Series is furnished unhardened with plain bore.
The “HM” Series is furnished hardened teeth with plain bore.
The “HMK” Series is furnished hardened teeth with keyway and
setscrew for installation on the shaft.
Hardened Miter Gears have approximately 50% more horsepower capacity and provide greater gear wear than untreated
gears.
All Martin Miter Gears are cut with the 20° pressure angle system. They will not operate with any other pressure angle system.
G49 - G64_G49 - G64 3/5/14 2:28 PM Page G-51
Miter Gears
20° Pressure Angle
Steel - Plain Bore — Unhardened Teeth
Number
Teeth
Diameter
Bore (Inches)
Diameter
Length
Mounting
(Inches)
Hub (Inches)
Diameter
Proj. (App.)
Catalog
Number
Pitch
Outside
Face
(Inches)
Wt. Lbs.
(App.)
M424
M424A
M428
6.00
6.00
7.00
6.36
6.36
7.36
1.33
1.33
1.43
11⁄2
13⁄4
2
39⁄16
39⁄16
35⁄8
51⁄2
51⁄2
6
4
4
5
115⁄16
115⁄16
115⁄16
14.4
13.7
21.1
M525
M525A
M525B
5.00
5.00
5.00
5.29
5.29
5.29
1.10
1.10
1.10
13⁄8
11⁄2
13⁄4
3
3
3
45⁄8
45⁄8
45⁄8
31⁄2
31⁄2
31⁄2
13⁄4
13⁄4
13⁄4
8.5
8.3
7.8
M624
M624A
M627
M627A
4.00
4.00
4.50
4.50
4.24
4.24
4.74
4.74
0.86
0.86
0.96
0.96
11⁄4
11⁄2
11⁄4
11⁄2
25⁄16
25⁄16
25⁄8
25⁄8
35⁄8
35⁄8
41⁄8
41⁄8
3
3
31⁄4
31⁄4
15⁄16
15⁄16
11⁄2
11⁄2
4.4
4.3
6.3
5.9
M824
M824A
M824B
M828
M828A
M828B
M832
3.00
3.00
3.00
3.50
3.50
3.50
4.00
3.18
3.18
3.18
3.68
3.68
3.68
4.18
0.64
0.64
0.64
0.75
0.75
0.75
0.84
3
⁄4
1
11⁄4
1
13⁄16
11⁄4
1
137⁄64
149⁄64
149⁄64
23⁄32
23⁄32
23⁄32
29⁄32
29⁄16
23⁄4
23⁄4
31⁄4
31⁄4
31⁄4
35⁄8
13⁄4
21⁄2
21⁄2
21⁄2
21⁄2
21⁄2
3
13
⁄16
1
1
11⁄4
11⁄4
11⁄4
11⁄8
1.5
2.1
1.9
2.9
2.8
2.6
4.8
M1020A
M1020B
M1020
M1020C
M1025
M1025A
M1025B
M1030
2.00
2.00
2.00
2.00
2.50
2.50
2.50
3.00
2.14
2.14
2.14
2.14
2.64
2.64
2.64
3.14
0.44
0.44
0.44
0.44
0.55
0.55
0.55
0.64
⁄2
⁄8
3
⁄4
7
⁄8
3
⁄4
7
⁄8
1
3
⁄4
123⁄64
123⁄64
123⁄64
123⁄64
15⁄8
15⁄8
15⁄8
13⁄4
2
2
2
2
27⁄16
27⁄16
27⁄16
23⁄4
15⁄8
15⁄8
15⁄8
15⁄8
2
2
2
2
13
⁄16
⁄16
⁄16
13
⁄16
15
⁄16
15
⁄16
15
⁄16
1
0.75
0.72
0.67
0.58
1.20
1.20
1.20
1.80
4 Pitch
24
24
28
5 Pitch
25
25
25
6 Pitch
24
24
27
27
8 Pitch
24
24
24
28
28
28
32
10 Pitch
20
20
20
20
25
25
25
30
1
5
13
13
G-51
G49 - G64_G49 - G64 3/5/14 2:28 PM Page G-52
Miter Gears
20° Pressure Angle
Steel - Plain Bore — Unhardened Teeth
Number
Teeth
Diameter
Bore (Inches)
Diameter
Length
Catalog
Number
Pitch
Outside
Face
(Inches)
M1215
M1215A
M1215B
M1218
M1218A
M1218B
M1221
M1221A
M1221B
M1221C
M1224
M1230
1.25
1.25
1.25
1.50
1.50
1.50
1.75
1.75
1.75
1.75
2.00
2.50
1.37
1.37
1.37
1.62
1.62
1.62
1.87
1.87
1.87
1.87
2.12
2.62
0.27
0.27
0.27
0.32
0.32
0.32
0.39
0.39
0.39
0.39
0.43
0.54
M1414
M1414A
1.00
1.00
1.11
1.11
0.19
0.19
M1612
M1616
M1620
M1624
0.75
1.00
1.25
1.50
0.84
1.09
1.34
1.59
0.16
0.22
0.27
0.31
M2020
M2025
1.00
1.25
1.07
1.32
0.23
0.25
M2424
1.00
1.06
0.20
1
Mounting
(Inches)
Hub (Inches)
Diameter
Proj. (App.)
Wt. Lbs.
(App.)
12 Pitch
15
15
15
18
18
18
21
21
21
21
24
30
3
⁄8
⁄16
1
⁄2
1
⁄2
5
⁄8
3
⁄4
1
⁄2
9
⁄16
5
⁄8
3
⁄4
1
⁄2
5
⁄8
55
7
55
⁄64
⁄64
55
⁄64
11⁄64
11⁄64
11⁄64
13⁄16
13⁄16
13⁄16
13⁄16
17⁄32
131⁄64
11⁄4
11⁄4
11⁄4
11⁄2
11⁄2
11⁄2
13⁄4
13⁄4
13⁄4
13⁄4
17⁄8
25⁄16
1
1
1
11⁄4
11⁄4
11⁄4
13⁄8
13⁄8
13⁄8
13⁄8
11⁄2
13⁄4
⁄2
⁄2
1
⁄2
5
⁄8
5
⁄8
5
⁄8
11
⁄16
11
⁄16
11
⁄16
11
⁄16
11
⁄16
27
⁄32
0.17
0.16
0.15
0.30
0.25
0.22
0.45
0.45
0.43
0.38
0.62
1.10
⁄64
⁄64
11⁄16
11⁄16
7
1
7
1
⁄2
⁄2
0.10
0.09
⁄16
11⁄16
11⁄4
13⁄8
5
3
3
7
⁄8
⁄16
⁄2
1
⁄2
0.05
0.07
0.16
0.20
⁄16
⁄4
11⁄8
13⁄16
3
⁄2
⁄8
0.06
0.14
⁄16
29
⁄32
5
⁄32
0.12
1
1
14 Pitch
14
14
3
⁄8
⁄16
47
7
47
5
⁄16
⁄8
7
⁄16
1
⁄2
37
3
3
3
⁄8
⁄8
13
3
3
⁄4
9
⁄8
⁄8
16 Pitch
12
16
20
24
⁄64
⁄4
27
⁄32
7
⁄8
13
⁄8
⁄4
1
1
1
20 Pitch
20
25
⁄4
1
1
⁄8
9
3
24 Pitch
24
G-52
G49 - G64_G49 - G64 3/5/14 2:28 PM Page G-53
Miter Gears
20° Pressure Angle
Steel - Plain Bore — Hardened Teeth
Number
Teeth
Diameter
Bore (Inches)
Diameter
Length
Catalog
Number
Pitch
Outside
Face
(Inches)
HM424
HM424A
HM428
6.00
6.00
7.00
6.36
6.36
7.36
1.33
1.33
1.43
11⁄2
13⁄4
2
39⁄16
39⁄16
35⁄8
HM525
HM525A
HM525B
5.00
5.00
5.00
5.29
5.29
5.29
1.10
1.10
1.10
13⁄8
11⁄2
13⁄4
3
3
3
HM624
HM624A
HM627
HM627A
4.00
4.00
4.50
4.50
4.24
4.24
4.74
4.74
0.86
0.86
0.96
0.96
11⁄4
11⁄2
11⁄4
11⁄2
HM824
HM824A
HM824B
HM828
HM828A
HM828B
HM832
3.00
3.00
3.00
3.50
3.50
3.50
4.00
3.18
3.18
3.18
3.68
3.68
3.68
4.18
0.64
0.64
0.64
0.75
0.75
0.75
0.85
HM1020A
HM1020B
HM1020
HM1020C
HM1025
HM1025A
HM1025B
HM1030
2.00
2.00
2.00
2.00
2.50
2.50
2.50
3.00
2.14
2.14
2.14
2.14
2.64
2.64
2.64
3.14
0.44
0.44
0.44
0.44
0.55
0.55
0.55
0.64
1
Mounting
(Inches)
Hub (Inches)
Diameter
Proj. (App.)
Wt. Lbs.
(App.)
4 Pitch
24
24
28
51⁄2
51⁄2
6
4
4
5
115⁄16
115⁄16
115⁄16
14.4
13.7
21.1
45⁄8
45⁄8
45⁄8
31⁄2
31⁄2
31⁄2
13⁄4
13⁄4
13⁄4
8.5
8.3
7.5
25⁄16
25⁄16
25⁄8
25⁄8
35⁄8
35⁄8
41⁄8
41⁄8
3
3
31⁄4
31⁄4
15⁄16
15⁄16
11⁄2
11⁄2
4.4
4.0
6.3
5.9
3
⁄4
1
11⁄4
1
13⁄16
11⁄4
1
137⁄64
149⁄64
149⁄64
23⁄32
23⁄32
23⁄32
29⁄32
29⁄16
23⁄4
23⁄4
31⁄4
31⁄4
31⁄4
35⁄8
13⁄4
21⁄2
21⁄2
21⁄2
21⁄2
21⁄2
3
13
⁄16
1
1
11⁄4
11⁄4
11⁄4
11⁄8
1.5
2.1
2.6
3.0
2.8
2.6
4.7
⁄2
⁄8
3
⁄4
7
⁄8
3
⁄4
7
⁄8
1
3
⁄4
123⁄64
123⁄64
123⁄64
123⁄64
15⁄8
15⁄8
15⁄8
13⁄4
2
2
2
2
27⁄16
27⁄16
27⁄16
23⁄4
15⁄8
15⁄8
15⁄8
15⁄8
2
2
2
2
13
⁄16
⁄16
⁄16
13
⁄16
15
⁄16
15
⁄16
15
⁄16
1
0.76
0.70
0.64
0.58
1.30
1.20
1.20
1.80
5 Pitch
25
25
25
6 Pitch
24
24
27
27
8 Pitch
24
24
24
28
28
28
32
10 Pitch
20
20
20
20
25
25
25
30
5
13
13
G-53
G49 - G64_G49 - G64 3/5/14 2:28 PM Page G-54
Miter Gears
20° Pressure Angle
Steel - Plain Bore — Hardened Teeth
Number
Teeth
Diameter
Bore (Inches)
Diameter
Length
Mounting
(Inches)
Hub (Inches)
Diameter
Proj. (App.)
Catalog
Number
Pitch
Outside
Face
(Inches)
15
15
HM1215
HM1215B
1.25
1.25
1.37
1.37
0.27
0.27
3
55
⁄64
⁄64
55
11⁄4
11⁄4
1
1
1
1
18
18
18
HM1218
HM1218A
HM1218B
1.50
1.50
1.50
1.62
1.62
1.62
0.32
0.32
0.32
1
⁄2
⁄8
3
⁄4
11⁄64
11⁄64
11⁄64
11⁄2
11⁄2
11⁄2
11⁄4
11⁄4
11⁄4
5
5
21
21
24
30
HM1221
HM1221B
HM1224
HM1230
1.75
1.75
2.00
2.50
1.87
1.87
2.12
2.62
0.39
0.39
0.43
0.54
1
⁄2
⁄8
1
⁄2
5
⁄8
13⁄16
13⁄16
17⁄32
131⁄64
13⁄4
13⁄4
17⁄8
25⁄16
13⁄8
13⁄8
11⁄2
13⁄4
11
HM1414
HM1414A
1.00
1.00
1.11
1.11
0.19
0.19
3
⁄8
⁄16
47
⁄64
⁄64
⁄8
⁄8
1
47
11⁄16
11⁄16
7
7
7
1
HM1616
HM1624
1.00
1.50
1.09
1.59
0.22
0.31
3
⁄8
⁄2
3
⁄4
⁄8
⁄4
1
7
7
11⁄16
13⁄8
3
1
HM2424
1.00
1.06
0.20
1
⁄4
9
⁄16
29
⁄32
5
⁄8
9
Wt. Lbs.
(App.)
12 Pitch
⁄8
⁄2
5
⁄2
⁄2
0.15
0.15
⁄8
⁄8
5
⁄8
0.30
0.25
0.22
⁄16
⁄16
11
⁄16
27
⁄32
0.22
0.42
0.62
1.10
⁄2
⁄2
0.10
0.10
⁄16
⁄2
0.07
0.20
⁄32
0.06
1
5
11
14 Pitch
14
14
16 Pitch
16
24
1
24 Pitch
24
G-54
G49 - G64_G49 - G64 3/5/14 2:28 PM Page G-55
Miter Gears
20° Pressure Angle
Steel - Furnished With Keyway and Set Screw — Hardened Teeth
Number
Teeth
Diameter
Bore (Inches)
Diameter
Length
Mounting
(Inches)
Hub (Inches)
Diameter
Proj. (App.)
Catalog
Number
Pitch
Outside
Face
(Inches)
Wt. Lbs.
(App.)
HMK424A
HMK428
6.00
7.00
6.36
7.36
1.33
1.43
13⁄4
2
39⁄16
35⁄8
51⁄2
6
4
5
115⁄16
115⁄16
13.7
20.4
HMK525
HMK525B
5.00
5.00
5.29
5.29
1.10
1.10
13⁄8
13⁄4
3
3
45⁄8
45⁄8
31⁄2
31⁄2
13⁄4
13⁄4
8.5
7.5
HMK624
HMK624A
HMK627
HMK627A
4.00
4.00
4.50
4.50
4.24
4.24
4.74
4.74
0.86
0.86
0.96
0.96
11⁄4
11⁄2
11⁄4
11⁄2
25⁄16
25⁄16
25⁄8
25⁄8
35⁄8
35⁄8
41⁄8
41⁄8
3
3
31⁄4
31⁄4
15⁄16
15⁄16
11⁄2
11⁄2
4.4
4.0
6.3
5.9
HMK824
HMK824A
HMK824B
HMK828
HMK828A
HMK828B
3.00
3.00
3.00
3.50
3.50
3.50
3.18
3.18
3.18
3.68
3.68
3.68
0.64
0.64
0.64
0.75
0.75
0.75
3
⁄4
1
11⁄4
1
13⁄16
11⁄4
137⁄64
149⁄64
149⁄64
23⁄32
23⁄32
23⁄32
29⁄16
23⁄4
23⁄4
31⁄4
31⁄4
31⁄4
13⁄4
21⁄2
21⁄2
21⁄2
21⁄2
21⁄2
13
⁄16
1
1
11⁄4
11⁄4
11⁄4
1.5
2.1
1.8
2.9
2.7
2.6
HMK1020A
HMK1020B
HMK1020
HMK1020C
HMK1025
HMK1025A
HMK1025B
2.00
2.00
2.00
2.00
2.50
2.50
2.50
2.14
2.14
2.14
2.14
2.64
2.64
2.64
0.44
0.44
0.44
0.44
0.55
0.55
0.55
⁄2
⁄8
3
⁄4
7
⁄8
3
⁄4
7
⁄8
1
123⁄64
123⁄64
123⁄64
123⁄64
15⁄8
15⁄8
15⁄8
2
2
2
2
27⁄16
27⁄16
27⁄16
15⁄8
15⁄8
15⁄8
15⁄8
2
2
2
13
⁄16
⁄16
⁄16
13
⁄16
15
⁄16
15
⁄16
15
⁄16
0.74
0.70
0.63
0.58
1.30
1.20
1.10
HMK1215B
HMK1218A
HMK1221B
HMK1230
1.25
1.50
1.75
2.50
1.37
1.62
1.87
2.62
0.27
0.32
0.39
0.54
1
⁄2
⁄8
5
⁄8
5
⁄8
55
⁄64
11⁄64
13⁄16
131⁄64
11⁄4
11⁄2
13⁄4
25⁄16
1
11⁄4
13⁄8
13⁄4
1
⁄2
⁄8
⁄16
27
⁄32
0.14
0.25
0.41
1.10
HMK1616
HMK1624
1.00
1.50
1.09
1.59
0.22
0.31
3
⁄8
⁄2
3
⁄4
⁄8
7
11⁄16
13⁄8
⁄4
1
7
1
⁄16
⁄2
0.07
0.20
4 Pitch
24
28
5 Pitch
25
25
6 Pitch
24
24
27
27
8 Pitch
24
24
24
28
28
28
10 Pitch
20
20
20
20
25
25
25
1
5
13
13
12 Pitch
15
18
21
30
5
5
11
16 Pitch
16
24
3
1
G-55
G49 - G64_G49 - G64 3/5/14 2:28 PM Page G-56
Miter Gear
Horsepower Ratings
Steel
Catalog
Number
M424
HM424
M428
HM428
M525
HM525
M624
HM624
M627
HM627
M824
HM824
M828
HM828
M832
HM832
M1020
HM1020
M1025
HM1025
M1030
HM1030
M1215
HM1215
M1218
HM1218
M1221
HM1221
M1224
HM1224
M1230
HM1230
M1414
HM1414
M1616
HM1616
M1620
HM1620
M1624
HM1624
M2020
HM2020
M2025
HM2025
10
25
0.80
1.40
1.07
1.90
0.45
0.75
0.25
0.40
0.30
0.50
0.10
0.20
0.15
0.25
0.20
0.33
0.03
0.05
0.06
0.10
0.08
0.15
0.01
0.02
0.01
0.02
0.02
0.04
0.03
0.05
0.05
0.09
1.90
3.33
2.50
4.50
1.05
1.90
0.55
1.00
0.75
1.33
0.25
0.40
0.33
0.60
0.45
0.80
0.08
0.15
0.15
0.25
0.20
0.33
0.02
0.04
0.03
0.05
0.05
0.10
0.07
0.12
0.12
0.21
0.01
0.02
0.01
0.02
0.02
0.04
0.03
0.05
0.01
0.02
0.02
0.04
50
3.60
6.30
4.80
8.40
2.00
3.60
1.10
1.90
1.40
2.50
0.50
0.80
0.70
1.20
0.90
1.50
0.20
0.30
0.30
0.50
0.40
0.70
0.05
0.10
0.08
0.15
0.11
0.20
0.15
0.25
0.25
0.40
0.02
0.04
0.02
0.04
0.04
0.07
0.06
0.10
0.02
0.04
0.03
0.05
100
6.40
11.20
8.40
14.70
3.70
6.50
2.00
3.50
2.50
4.40
0.90
1.50
1.20
2.10
1.60
2.80
0.30
0.50
0.50
0.90
0.70
1.30
0.10
0.17
0.14
0.25
0.20
0.33
0.25
0.47
0.44
0.75
0.05
0.09
0.05
0.09
0.08
0.15
0.12
0.21
0.04
0.07
0.06
0.10
Ratings listed to right of dark line exceed recommended pitch line velocity.
G-56
Revolutions Per Minute
200
300
10.60
18.60
13.60
23.80
6.30
11.00
3.50
6.10
4.30
7.50
1.50
2.60
2.20
3.90
2.80
4.90
0.60
1.00
0.90
1.60
1.30
2.30
0.20
0.33
0.25
0.47
0.40
0.70
0.50
0.90
0.80
1.40
0.09
0.16
0.09
0.16
0.14
0.25
0.20
0.40
0.08
0.14
0.12
0.21
13.5
23.6
17.2
30.0
8.1
14.2
4.6
8.0
5.7
10.0
2.1
3.7
2.9
5.0
3.7
6.5
0.8
1.4
1.3
2.3
1.8
3.2
0.3
0.4
0.4
0.7
0.5
1.0
0.7
1.2
1.1
1.9
0.1
0.2
0.1
0.2
0.2
0.4
0.3
0.5
0.1
0.2
0.2
0.3
600
900
1200
1800
18.8
33.0
23.3
40.0
11.6
20.0
6.9
12.0
8.5
1.5
3.3
5.8
4.4
7.7
5.5
9.6
1.3
2.3
2.0
3.5
2.8
4.9
0.5
0.8
0.7
1.1
0.9
1.6
1.2
2.1
1.8
3.2
0.2
0.4
0.2
0.4
0.4
0.7
0.5
0.9
0.2
0.4
0.3
0.5
21.5
38.0
26.5
46.0
13.6
24.0
8.2
14.5
9.9
17.5
4.0
7.0
5.3
9.3
6.5
11.4
1.7
3.0
2.5
4.4
3.5
6.1
0.6
1.0
0.9
1.5
1.2
2.1
1.5
2.6
2.2
4.0
0.3
0.6
0.3
0.6
0.5
0.9
0.7
1.2
0.2
0.5
0.4
0.7
23.0
40.0
28.5
50.0
15.0
26.0
19.0
16.0
11.0
19.0
4.5
8.0
6.0
10.5
7.2
12.5
2.0
3.5
2.9
5.0
3.9
6.8
0.8
1.3
1.0
1.8
1.4
2.5
1.7
3.0
2.5
4.4
0.4
0.7
0.4
0.7
0.6
1.0
0.8
1.4
0.4
0.6
0.5
0.9
10.2
18.0
12.0
21.0
5.3
9.3
6.8
12.0
8.0
14.2
2.4
4.2
3.5
6.0
4.5
8.0
0.9
1.6
1.3
2.2
1.7
3.0
2.0
3.5
3.0
5.3
0.5
0.9
0.5
0.9
0.8
1.3
1.0
1.8
0.5
0.8
0.6
1.0