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Spur Gear Cutter Selection Chart | Travers Tool Co.

Written by Travers Team | Apr 18, 2023, 3:04:55 AM

Choose the Right Spur Gear Cutter, Every Time

Involute & Module Involute Cutters, 14-1/2° and 20° Pressure Angles — All In One Place

Use this guide to determine the right spur gear cutter for your application. You only need three numbers: the diametrical pitch (or module, for metric gears), the pressure angle, and the total number of teeth on the gear. Then follow the five steps below to find your Travers item number.

You’ll get:

  • Cutter number ranges by number of teeth
  • 14-1/2° and 20° involute (standard) cutter item numbers
  • 14-1/2° and 20° module involute (metric) cutter item numbers
  • Cutter diameter and hole size for every pitch and module

 
To select a spur gear cutter, you need the diametrical pitch (or module), the pressure angle, and the number of teeth on your gear. The tooth count gives you the cutter number (#1 through #8). Your pressure angle and gear type (standard or metric) give you the chart, and your pitch or module gives you the row. Where your cutter number column meets your pitch or module row is your Travers item number. Cutters cover gears from 12 teeth to a rack.

What you need before you start

  • Diametrical pitch (for metric gears, this is the module)
  • Pressure angle (14-1/2° or 20° for most gears)
  • Total number of teeth on the gear

How to select your spur gear cutter in 5 steps

  1. Step 1: Use the range charts below to find the cutter number based on the number of teeth on your gear.
  2. Step 2: Find the chart that matches your gear: 14-1/2° or 20° pressure angle, and involute (standard) or module involute (metric).
  3. Step 3: In the first column of that chart, find the diametrical pitch (or module) of the gear you are making.
  4. Step 4: On the top row, find the cutter number from Step 1.
  5. Step 5: Look to the right of your pitch and below your cutter number to find the Travers item number.
Example: You are making a standard involute gear with 20 teeth, 8 diametrical pitch and a 20° pressure angle. A 20-tooth gear falls in the 17 to 20 teeth range, so you need a #6 cutter. In the 20° involute chart, the 8 diametrical pitch row under Cutter #6 gives item number 10-289-086.

Step 1: Find your cutter number

Involute gear cutters

Range of cutters by number of teeth on the gear

Cutter # # of teeth of gear
1 135 teeth to rack
2 55 to 134 teeth
3 35 to 54 teeth
4 26 to 34 teeth
5 21 to 25 teeth
6 17 to 20 teeth
7 14 to 16 teeth
8 12 to 13 teeth

Specify cutter # and pitch when ordering.

 

Involute module gear cutters (metric): module marking guide

Module cutters are marked two ways: TTC standard markings and industry standard markings.

TTC standard: cutter # TTC standard: # of teeth Industry standard: cutter # Industry standard: # of teeth
1 135 teeth to rack 1 12 to 13 teeth
2 55 to 134 teeth 2 14 to 16 teeth
3 35 to 54 teeth 3 17 to 20 teeth
4 26 to 34 teeth 4 21 to 25 teeth
5 21 to 25 teeth 5 26 to 34 teeth
6 17 to 20 teeth 6 35 to 54 teeth
7 14 to 16 teeth 7 55 to 134 teeth
8 12 to 13 teeth 8 135 teeth to rack

Steps 2–5: Find your Travers item number

Pick the chart that matches your gear. Items in each chart are listed by diametrical pitch (or module) down the left side and cutter number across the top.

14-1/2° pressure angle involute (standard) spur gears

Involute gear cutters (E18)

Diametrical Pitch Cutter Diameter (in.) Hole Size (in.) Cutter #1 Cutter #2 Cutter #3 Cutter #4 Cutter #5 Cutter #6 Cutter #7 Cutter #8
2* 5-3/4 1-1/2 10-281-020 10-282-020 10-283-020 10-284-020 10-285-020 10-286-020 10-287-020 10-288-020
2-1/2* 5-3/4 1-1/2 10-281-025 10-282-025 10-283-025 10-284-025 10-285-025 10-286-025 10-287-025 10-288-025
3* 5-1/4 1-1/4 10-281-030 10-282-030 10-283-030 10-284-030 10-285-030 10-286-030 10-287-030 10-288-030
4 4-1/4 1-1/4 10-281-040 10-282-040 10-283-040 10-284-040 10-285-040 10-286-040 10-287-040 10-288-040
5 3-5/8 1-1/4 10-281-050 10-282-050 10-283-050 10-284-050 10-285-050 10-286-050 10-287-050 10-288-050
6 3-1/2 1-1/4 10-281-060 10-282-060 10-283-060 10-284-060 10-285-060 10-286-060 10-287-060 10-288-060
7* 2-7/8 1 10-281-070 10-282-070 10-283-070 10-284-070 10-285-070 10-286-070 10-287-070 10-288-070
8 2-7/8 1 10-281-080 10-282-080 10-283-080 10-284-080 10-285-080 10-286-080 10-287-080 10-288-080
9* 2-3/4 1 10-281-090 10-282-090 10-283-090 10-284-090 10-285-090 10-286-090 10-287-090 10-288-090
10 2-3/4 1 10-281-100 10-282-100 10-283-100 10-284-100 10-285-100 10-286-100 10-287-100 10-288-100
11* 2-3/8 1 10-281-110 10-282-110 10-283-110 10-284-110 10-285-110 10-286-110 10-287-110 10-288-110
12 2-5/8 1 10-281-120 10-282-120 10-283-120 10-284-120 10-285-120 10-286-120 10-287-120 10-288-120
14 2-1/2 1 10-281-140 10-282-140 10-283-140 10-284-140 10-285-140 10-286-140 10-287-140 10-288-140
16 2-1/2 1 10-281-160 10-282-160 10-283-160 10-284-160 10-285-160 10-286-160 10-287-160 10-288-160
18 2-3/8 1 10-281-180 10-282-180 10-283-180 10-284-180 10-285-180 10-286-180 10-287-180 10-288-180
20 2-3/8 1 10-281-200 10-282-200 10-283-200 10-284-200 10-285-200 10-286-200 10-287-200 10-288-200
22* 2 7/8 10-281-220 10-282-220 10-283-220 10-284-220 10-285-220 10-286-220 10-287-220 10-288-220
24* 1-3/4 7/8 10-281-240 10-282-240 10-283-240 10-284-240 10-285-240 10-286-240 10-287-240 10-288-240
26* 1-3/4 7/8 10-281-260 10-282-260 10-283-260 10-284-260 10-285-260 10-286-260 10-287-260 10-288-260
28* 1-3/4 7/8 10-281-280 10-282-280 10-283-280 10-284-280 10-285-280 10-286-280 10-287-280 10-288-280
30* 1-3/4 7/8 10-281-300 10-282-300 10-283-300 10-284-300 10-285-300 10-286-300 10-287-300 10-288-300
32 2-1/4 1 10-281-320 10-282-320 10-283-320 10-284-320 10-285-320 10-286-320 10-287-320 10-288-320
48 1-3/4 7/8 10-281-480 10-282-480 10-283-480 10-284-480 10-285-480 10-286-480 10-287-480 10-288-480

*Special sizes

20° pressure angle involute (standard) spur gears

Involute gear cutters (E188)

Diametrical Pitch Cutter Diameter (in.) Hole Size (in.) Cutter #1 Cutter #2 Cutter #3 Cutter #4 Cutter #5 Cutter #6 Cutter #7 Cutter #8
4 3-5/8 1-1/4 10-289-041 10-289-042 10-289-043 10-289-044 10-289-045 10-289-046 10-289-047 10-289-048
5 3-3/4 1-1/4 10-289-051 10-289-052 10-289-053 10-289-054 10-289-055 10-289-056 10-289-057 10-289-058
6 3-1/2 1-1/4 10-289-061 10-289-062 10-289-063 10-289-064 10-289-065 10-289-066 10-289-067 10-289-068
7 2-7/8 1 10-289-071 10-289-072 10-289-073 10-289-074 10-289-075 10-289-076 10-289-077 10-289-078
8 2-7/8 1 10-289-081 10-289-082 10-289-083 10-289-084 10-289-085 10-289-086 10-289-087 10-289-088
9 2-3/4 1 10-289-091 10-289-092 10-289-093 10-289-094 10-289-095 10-289-096 10-289-097 10-289-098
10 2-3/4 1 10-289-101 10-289-102 10-289-103 10-289-104 10-289-105 10-289-106 10-289-107 10-289-108
12 2-5/8 1 10-289-121 10-289-122 10-289-123 10-289-124 10-289-125 10-289-126 10-289-127 10-289-128
14 2-1/2 1 10-289-141 10-289-142 10-289-143 10-289-144 10-289-145 10-289-146 10-289-147 10-289-148
16 2-1/2 1 10-289-161 10-289-162 10-289-163 10-289-164 10-289-165 10-289-166 10-289-167 10-289-168
18 2-3/8 1 10-289-181 10-289-182 10-289-183 10-289-184 10-289-185 10-289-186 10-289-187 10-289-188
20 2-3/8 1 10-289-201 10-289-202 10-289-203 10-289-204 10-289-205 10-289-206 10-289-207 10-289-208
24 2-1/4 1 10-289-241 10-289-242 10-289-243 10-289-244 10-289-245 10-289-246 10-289-247 10-289-248
32 2-1/4 1 10-289-321 10-289-322 10-289-323 10-289-324 10-289-325 10-289-326 10-289-327 10-289-328
40 1-3/4 7/8 10-289-401 10-289-402 10-289-403 10-289-404 10-289-405 10-289-406 10-289-407 10-289-408
48 1-3/4 7/8 10-289-481 10-289-482 10-289-483 10-289-484 10-289-485 10-289-486 10-289-487 10-289-488

14-1/2° pressure angle module involute (metric) spur gears

Module involute gear cutters (E28)

Module Cutter Diameter (in.) Hole Size (in.) Cutter #1 Cutter #2 Cutter #3 Cutter #4 Cutter #5 Cutter #6 Cutter #7 Cutter #8
1 2 1 10-290-301 10-290-302 10-290-303 10-290-304 10-290-305 10-290-306 10-290-307 10-290-308
1-1/4 2 1 10-290-311 10-290-312 10-290-313 10-290-314 10-290-315 10-290-316 10-290-317 10-290-318
1-1/2 2 1 10-290-321 10-290-322 10-290-323 10-290-324 10-290-325 10-290-326 10-290-327 10-290-328
1-3/4 2-1/4 1 10-290-331 10-290-332 10-290-333 10-290-334 10-290-335 10-290-336 10-290-337 10-290-338
2 2-1/2 1 10-290-341 10-290-342 10-290-343 10-290-344 10-290-345 10-290-346 10-290-347 10-290-348
2-1/4 2-1/2 1 10-290-351 10-290-352 10-290-353 10-290-354 10-290-355 10-290-356 10-290-357 10-290-358
2-1/2 2-1/2 1 10-290-361 10-290-362 10-290-363 10-290-364 10-290-365 10-290-366 10-290-367 10-290-368
2-3/4 2-1/2 1 10-290-371 10-290-372 10-290-373 10-290-374 10-290-375 10-290-376 10-290-377 10-290-378
3 2-1/2 1 10-290-381 10-290-382 10-290-383 10-290-384 10-290-385 10-290-386 10-290-387 10-290-388
3-1/4 2-1/2 1-1/4 10-290-391 10-290-392 10-290-393 10-290-394 10-290-395 10-290-396 10-290-397 10-290-398
3-1/2 2-1/2 1-1/4 10-290-401 10-290-402 10-290-403 10-290-404 10-290-405 10-290-406 10-290-407 10-290-408
4 3 1 10-290-411 10-290-412 10-290-413 10-290-414 10-290-415 10-290-416 10-290-417 10-290-418

20° pressure angle module involute (metric) spur gears

Module involute gear cutters (E29)

Module Cutter Diameter (in.) Hole Size (in.) Cutter #1 Cutter #2 Cutter #3 Cutter #4 Cutter #5 Cutter #6 Cutter #7 Cutter #8
1 2 1 10-290-011 10-290-012 10-290-013 10-290-014 10-290-015 10-290-016 10-290-017 10-290-018
1-1/4 2 1 10-290-021 10-290-022 10-290-023 10-290-024 10-290-025 10-290-026 10-290-027 10-290-028
1-1/2 2-1/4 1 10-290-031 10-290-032 10-290-033 10-290-034 10-290-035 10-290-036 10-290-037 10-290-038
1-3/4 2-1/4 1 10-290-041 10-290-042 10-290-043 10-290-044 10-290-045 10-290-046 10-290-047 10-290-048
2 2-1/2 1 10-290-051 10-290-052 10-290-053 10-290-054 10-290-055 10-290-056 10-290-057 10-290-058
2-1/4 2-5/8 1 10-290-061 10-290-062 10-290-063 10-290-064 10-290-065 10-290-066 10-290-067 10-290-068
2-1/2 2-3/4 1 10-290-071 10-290-072 10-290-073 10-290-074 10-290-075 10-290-076 10-290-077 10-290-078
2-3/4 2-7/8 1 10-290-081 10-290-082 10-290-083 10-290-084 10-290-085 10-290-086 10-290-087 10-290-088
3 2-7/8 1 10-290-091 10-290-092 10-290-093 10-290-094 10-290-095 10-290-096 10-290-097 10-290-098
3-1/4 3 1 10-290-101 10-290-102 10-290-103 10-290-104 10-290-105 10-290-106 10-290-107 10-290-108
3-1/2 3 1 10-290-111 10-290-112 10-290-113 10-290-114 10-290-115 10-290-116 10-290-117 10-290-118
3-3/4 3-1/4 1 10-290-121 10-290-122 10-290-123 10-290-124 10-290-125 10-290-126 10-290-127 10-290-128
4 3-1/4 1 10-290-131 10-290-132 10-290-133 10-290-134 10-290-135 10-290-136 10-290-137 10-290-138
4-1/4 4 1 10-290-141 10-290-142 10-290-143 10-290-144 10-290-145 10-290-146 10-290-147 10-290-148
4-1/2 4 1 10-290-151 10-290-152 10-290-153 10-290-154 10-290-155 10-290-156 10-290-157 10-290-158
5 4 1 10-290-161 10-290-162 10-290-163 10-290-164 10-290-165 10-290-166 10-290-167 10-290-168
5-1/2 4 1 10-290-171 10-290-172 10-290-173 10-290-174 10-290-175 10-290-176 10-290-177 10-290-178
6 4 1 10-290-181 10-290-182 10-290-183 10-290-184 10-290-185 10-290-186 10-290-187 10-290-188
7 4-3/4 1-1/4 10-290-191 10-290-192 10-290-193 10-290-194 10-290-195 10-290-196 10-290-197 10-290-198
8 4-3/4 1-1/4 10-290-201 10-290-202 10-290-203 10-290-204 10-290-205 10-290-206 10-290-207 10-290-208
8-1/2 5-1/4 1-1/2 10-290-211 10-290-212 10-290-213 10-290-214 10-290-215 10-290-216 10-290-217 10-290-218
9 5-1/4 1-1/2 10-290-221 10-290-222 10-290-223 10-290-224 10-290-225 10-290-226 10-290-227 10-290-228
9-1/2 5-1/2 1-1/2 10-290-231 10-290-232 10-290-233 10-290-234 10-290-235 10-290-236 10-290-237 10-290-238
10 5-1/2 1-1/2 10-290-241 10-290-242 10-290-243 10-290-244 10-290-245 10-290-246 10-290-247 10-290-248

Need every chart on one free printable sheet?

Download the complete Spur Gear Cutter Selection Guide PDF: all four item charts and both cutter range tables.

Spur gear cutter basics

Diametrical pitch and module

Standard involute gears are specified by diametrical pitch. Metric gears are specified by module. Use the involute (standard) charts for diametrical pitch and the module involute (metric) charts for module.

Pressure angle

Check whether your gear has a 14-1/2° or a 20° pressure angle. These are the two pressure angles for most gears. The item charts are organized by pressure angle and by involute (standard) or module involute (metric).

How cutter numbers work

Cutter numbers #1 through #8 each cover a range of teeth. For standard involute cutters, #1 covers 135 teeth to rack and #8 covers 12 to 13 teeth. Find your cutter number from your tooth count first, then look up the item number by pitch or module.

Before you order

  • Confirm your gear’s pressure angle (14-1/2° or 20°) and whether it is specified by diametrical pitch or module.
  • Count the total teeth on the gear and find your cutter number (#1 through #8) in the Step 1 charts.
  • Check the cutter diameter and hole size listed next to your pitch or module.
  • Specify the cutter number and pitch (or module) when ordering. Items marked with an asterisk in the 14-1/2° involute chart are special sizes.

Shop the tools for the job

Frequently asked questions

What information do I need to select a spur gear cutter?

You need three things: the diametrical pitch (or module, for metric gears), the pressure angle (14-1/2° or 20° for most gears), and the total number of teeth on the gear.

How do I find my cutter number?

The cutter number comes from the number of teeth on your gear. For standard involute cutters, a gear with 17 to 20 teeth uses a #6 cutter, and a gear with 35 to 54 teeth uses a #3 cutter. Check the range chart above for your tooth count.

What is the difference between a 14-1/2° and a 20° pressure angle cutter?

The cutter must match the pressure angle of the gear you are making. Use the 14-1/2° charts for 14-1/2° gears and the 20° charts for 20° gears.

What is the difference between involute and module involute cutters?

Standard involute cutters (E18 and E188) are listed by diametrical pitch. Module involute (metric) cutters (E28 and E29) are listed by module. Use the chart that matches how your gear is specified.

Why do the metric cutters show two sets of markings?

Travers (TTC) standard markings number the module cutters in the same order as the standard involute cutters, starting with #1 for the largest tooth counts. Industry standard markings number them in the reverse order. Both are shown in the module marking guide above.

Where do I find the cutter diameter and hole size?

Both are listed in the second and third columns of each item chart, next to the diametrical pitch or module.

What do the asterisks in the chart mean?

Items marked with an asterisk in the 14-1/2° involute chart are special sizes.

What do I need to specify when ordering?

Specify the cutter number and the pitch (or module) when ordering. Each cutter number has its own Travers item number in the charts.

Who can help if I can’t find my size?

Call the Travers expert tech support team at 800.234.9985, or submit a request online. Have your diametrical pitch (or module), pressure angle and total number of teeth ready.
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