Machinery''''s Handbook 27th Episode 3 Part 6 doc

Machinery's Handbook 27th Edition MILLING MACHINE INDEXING 1995 Table 3 (Continued) Accurate Angular Indexing Part of a Turn 0.1910 0.1915 0.1920 0.1930 0.1930 0.1935 0.1940 0.1950 0.1951 0.1957 0.1960 0.1961 0.1970 0.1970 0.1980 0.1990 0.2000 0.2000 0.2010 0.2020 0.2030 0.2034 0.2037 0.2040 0.2041 0.2050 0.2051 0.2059 0.2060 0.2069 0.2070 0.2075 0.2080 0.2083 0.2090 0.2093 0.2097 0.2100 0.2105 0.2105 0.2110 0.2120 0.2121 0.2128 0.2130 0.2140 0.2143 0.2143 0.2150 0.2157 0.2160 0.2162 0.2170 0.2174 0.2180 0.2190 0.2195 0.2200 0.2203 0.2210 0.2220 B&S, Becker, Hendey, K&T, & Rockford 17/39 − 12/49 9/47 7/41 + 1/47 … 10/19 − 5/15 6/31 7/41 + 1/43 1/23 + 5/33 8/41 … 21/49 − 10/43 … … 21/39 − 14/41 2/29 + 4/31 5/37 + 3/47 3/15 4/20 11/39 − 3/37 23/41 − 14/39 2/37 + 7/47 … … 12/47 − 2/39 10/49 13/37 − 6/41 8/39 … 15/43 − 7/49 6/29 19/41 − 10/39 … 15/31 − 8/29 … 16/33 − 8/29 9/43 … 22/37 − 15/39 4/19 … 22/41 − 14/43 2/27 − 4/29 7/33 10/47 23/49 − 10/39 20/37 − 16/49 … … 11/43 − 2/49 … 2/23 + 4/31 8/37 11/41 − 2/39 5/23 3/31 + 4/33 11/23 − 7/27 9/41 4/41 + 6/49 … 18/49 − 6/41 25/41 − 19/49 Cincinnati and LeBlond 21/57 − 11/62 9/47 12/57 − 1/54 11/57 19/59 − 8/62 12/62 14/43 − 5/38 8/25 − 3/24 8/41 9/46 34/66 − 15/47 10/51 13/66 11/47 − 2/54 17/49 − 7/47 27/59 − 15/58 5/25 6/30 8/49 + 2/53 23/41 − 14/39 19/62 − 6/58 12/59 11/54 18/51 − 7/47 10/49 3/24 + 2/25 8/39 7/34 12/53 − 1/49 12/58 19/41 − 10/39 11/53 13/58 − 1/62 5/24 8/46 + 2/57 9/43 13/62 6/24 − 1/25 8/38 12/57 22/41 − 14/43 4/54 + 8/58 14/66 10/47 2/30 + 6/41 12/51 − 1/47 6/28 9/42 9/24 − 4/25 11/51 25/51 − 17/62 8/37 28/59 − 17/66 10/46 21/59 − 8/58 3/47 + 9/58 9/41 3/25 + 3/30 13/59 21/47 − 14/62 7/51 + 5/59 Part of a Turn 0.2222 0.2222 0.2230 0.2240 0.2241 0.2245 0.2250 0.2258 0.2260 0.2264 0.2270 0.2273 0.2280 0.2281 0.2290 0.2300 0.2308 0.2310 0.2320 0.2326 0.2330 0.2333 0.2340 0.2340 0.2350 0.2353 0.2353 0.2360 0.2368 0.2370 0.2373 0.2380 0.2381 0.2390 0.2391 0.2400 0.2407 0.2410 0.2414 0.2419 0.2420 0.2424 0.2430 0.2432 0.2439 0.2440 0.2449 0.2450 0.2453 0.2456 0.2460 0.2470 0.2480 0.2490 0.2500 0.2500 0.2510 0.2520 0.2530 0.2540 0.2542 B&S, Becker, Hendey, K&T, & Rockford 4/18 6/27 15/31 − 6/23 5/41 + 5/49 … 11/49 2/16 + 2/20 7/31 7/39 + 2/43 … 7/27 − 1/31 … 11/39 − 2/37 … 18/39 − 10/43 7/37 + 2/49 9/39 28/49 − 16/47 20/41 − 11/43 10/43 27/47 − 14/41 … 24/41 − 13/37 11/47 11/27 − 5/29 4/17 … 10/39 − 1/49 … 23/37 − 15/39 … 2/43 + 9/47 5/21 24/43 − 15/47 … 3/43 + 8/47 … 19/47 − 8/49 7/29 … 21/37 − 14/43 8/33 29/49 − 15/43 9/37 10/41 13/49 − 1/47 12/49 13/37 − 5/47 … … 20/49 − 6/37 10/37 − 1/43 4/23 + 2/27 10/37 − 1/47 4/16 5/20 2/15 + 2/17 24/43 − 15/49 7/37 + 3/47 26/49 − 13/47 … Copyright 2004, Industrial Press, Inc., New York, NY Cincinnati and LeBlond … 12/54 11/46 − 1/62 15/38 − 7/41 13/58 11/49 3/24 + 3/30 14/62 2/49 + 10/54 12/53 14/54 − 2/62 15/66 23/49 − 14/58 13/57 29/51 − 18/53 12/25 − 6/24 9/39 26/59 − 13/62 26/57 − 13/58 10/43 25/62 − 8/47 7/30 2/54 + 13/66 11/47 9/25 − 3/24 8/34 12/51 29/66 − 12/59 9/38 23/37 − 15/39 14/59 34/57 − 19/53 10/42 12/62 + 3/66 11/46 6/25 13/54 17/47 − 7/58 14/58 15/62 12/46 − 1/53 16/66 4/47 + 9/57 9/37 10/41 30/53 − 19/59 12/49 3/24 + 3/25 13/53 14/57 11/37 − 2/39 29/49 − 20/58 26/49 − 13/46 17/43 − 6/41 6/24 7/28 34/66 − 14/53 22/49 − 13/66 11/53 + 3/66 2/46 + 12/57 15/59 Machinery's Handbook 27th Edition 1996 MILLING MACHINE INDEXING Table 3 (Continued) Accurate Angular Indexing Part of a Turn 0.2549 0.2550 0.2553 0.2558 0.2560 0.2564 0.2570 0.2576 0.2580 0.2581 0.2586 0.2590 0.2593 0.2600 0.2609 0.2610 0.2619 0.2620 0.2630 0.2632 0.2632 0.2640 0.2642 0.2647 0.2650 0.2653 0.2660 0.2667 0.2670 0.2680 0.2683 0.2690 0.2700 0.2703 0.2710 0.2712 0.2720 0.2727 0.2730 0.2740 0.2742 0.2745 0.2750 0.2759 0.2760 0.2766 0.2770 0.2778 0.2780 0.2790 0.2791 0.2800 0.2807 0.2810 0.2820 0.2821 0.2826 0.2830 0.2840 0.2850 0.2857 B&S, Becker, Hendey, K&T, & Rockford … 4/21 + 2/31 12/47 11/43 13/33 − 4/29 10/39 20/39 − 11/43 … 15/29 − 7/27 8/31 … 24/49 − 9/39 7/27 20/43 − 8/39 6/23 15/33 − 6/31 … 18/37 − 11/49 13/41 − 2/37 5/19 … 22/47 − 10/49 … … 8/37 + 2/41 13/49 8/27 − 1/33 … 18/37 − 9/41 8/18 − 3/17 11/41 2/18 + 3/19 16/27 − 10/31 10/37 2/43 + 11/49 … 14/37 − 5/47 9/33 1/16 + 4/19 6/41 + 6/47 … … 2/16 + 3/20 8/29 12/31 − 3/27 13/47 11/27 − 3/23 5/18 5/23 + 2/33 16/29 − 9/33 12/43 16/49 − 2/43 … 3/39 + 10/49 5/27 + 3/31 11/39 … 14/43 − 2/47 21/47 − 7/43 15/43 − 3/47 14/49 Cincinnati and LeBlond 13/51 9/24 − 3/25 12/47 11/43 9/47 + 4/62 10/39 8/53 + 7/66 17/66 24/54 − 11/59 16/62 15/58 16/42 − 5/41 14/54 4/25 + 3/30 12/46 5/53 + 9/54 11/42 16/51 − 3/58 13/46 − 1/51 10/38 15/57 22/47 − 10/49 14/53 9/34 15/24 − 9/25 13/49 28/51 − 15/53 8/30 19/47 − 7/51 27/49 − 15/53 11/41 6/54 + 9/57 13/25 − 6/24 10/37 1/28 + 8/34 16/59 17/59 − 1/62 18/66 18/34 − 10/39 26/59 − 9/54 17/62 14/51 5/24 + 2/30 16/58 13/43 − 1/38 13/47 18/28 − 15/41 15/54 17/39 − 6/38 14/47 − 1/53 12/43 7/25 16/57 17/57 − 1/58 24/66 − 4/49 11/39 13/46 15/53 37/66 − 13/47 3/24 + 4/25 14/49 Part of a Turn 0.2857 0.2857 0.2860 0.2870 0.2879 0.2880 0.2881 0.2890 0.2895 0.2900 0.2903 0.2910 0.2917 0.2920 0.2927 0.2930 0.2931 0.2940 0.2941 0.2941 0.2950 0.2960 0.2963 0.2970 0.2973 0.2979 0.2980 0.2982 0.2990 0.3000 0.3010 0.3019 0.3020 0.3023 0.3030 0.3030 0.3040 0.3043 0.3050 0.3051 0.3060 0.3061 0.3065 0.3070 0.3077 0.3080 0.3090 0.3095 0.3100 0.3103 0.3110 0.3120 0.3125 0.3130 0.3137 0.3140 0.3148 0.3150 0.3158 0.3158 0.3160 B&S, Becker, Hendey, K&T, & Rockford … … 20/47 − 6/43 7/41 + 5/43 … 19/43 − 6/39 … 1/21 + 7/29 … 23/43 − 12/49 9/31 5/39 + 7/43 … 9/39 + 3/49 12/41 17/39 − 7/49 … 8/21 − 2/23 5/17 … 18/37 − 9/47 21/41 − 8/37 8/27 3/29 + 6/31 11/37 14/47 11/21 − 7/31 … 19/43 − 7/49 6/20 1/41 + 13/47 … 7/29 + 2/33 13/43 15/39 − 4/49 10/33 16/31 − 7/33 7/23 1/31 + 9/33 … 17/31 − 8/33 15/49 … 18/37 − 7/39 12/39 5/41 + 8/43 1/43 + 14/49 … 16/37 − 6/49 9/29 3/39 + 11/47 8/21 − 2/29 5/16 9/37 + 3/43 … 12/27 − 3/23 … 26/41 − 15/47 … … 6/37 + 6/39 Copyright 2004, Industrial Press, Inc., New York, NY Cincinnati and LeBlond 12/42 8/28 20/58 − 3/51 20/42 − 7/37 19/66 19/43 − 6/39 17/59 16/46 − 3/51 11/38 6/24 + 1/25 18/62 7/49 + 8/54 7/24 35/57 − 19/59 12/41 28/53 − 12/51 17/58 14/57 + 3/62 10/34 15/51 9/24 − 2/25 29/57 − 10/47 16/54 13/47 + 1/49 11/37 14/47 12/37 − 1/38 17/57 19/43 − 4/28 9/30 19/54 − 3/59 16/53 23/62 − 4/58 13/43 25/57 − 8/59 20/66 33/59 − 12/47 14/46 15/24 − 8/25 18/59 33/54 − 18/59 15/49 19/62 1/53 + 17/59 12/39 16/49 − 1/54 19/30 − 12/37 13/42 14/25 − 6/24 18/58 19/46 − 5/49 2/49 + 16/59 … 4/24 + 6/41 16/51 14/47 + 1/62 17/54 21/24 − 14/25 12/38 18/57 6/34 + 6/43 Machinery's Handbook 27th Edition MILLING MACHINE INDEXING 1997 Table 3 (Continued) Accurate Angular Indexing Part of a Turn 0.3170 0.3171 0.3180 0.3182 0.3190 0.3191 0.3200 0.3208 0.3210 0.3214 0.3220 0.3220 0.3226 0.3230 0.3235 0.3240 0.3243 0.3250 0.3256 0.3260 0.3261 0.3265 0.3270 0.3276 0.3280 0.3290 0.3300 0.3310 0.3320 0.3330 0.3333 0.3333 0.3333 0.3333 0.3333 0.3333 0.3333 0.3333 0.3340 0.3350 0.3360 0.3370 0.3380 0.3387 0.3390 0.3396 0.3400 0.3404 0.3410 0.3415 0.3420 0.3421 0.3430 0.3440 0.3448 0.3450 0.3460 0.3469 0.3470 0.3478 0.3480 B&S, Becker, Hendey, K&T, & Rockford 11/18 − 5/17 13/41 22/37 − 13/47 … 6/27 + 3/31 15/47 16/47 − 1/49 … 25/49 − 7/37 … 18/39 − 6/43 … 10/31 21/41 − 7/37 … 3/23 + 6/31 12/37 2/16 + 4/20 14/43 21/49 − 4/39 … 16/49 24/49 − 7/43 … 26/41 − 15/49 5/21 + 3/33 4/47 + 12/49 17/31 − 5/23 28/43 − 15/47 7/43 + 8/47 5/15 6/18 7/21 9/27 11/33 13/39 … … 7/41 + 8/49 21/37 − 10/43 28/41 − 17/49 2/39 + 14/49 10/23 − 3/31 … 19/49 − 2/41 … 25/49 − 8/47 16/47 12/27 − 3/29 14/41 4/21 + 5/33 … 13/23 − 6/27 2/39 + 12/41 … 2/23 + 8/31 18/41 − 4/43 17/49 7/31 + 4/33 8/23 20/33 − 8/31 Cincinnati and LeBlond 34/59 − 14/54 13/41 6/54 + 12/58 21/66 3/34 + 9/39 15/47 8/25 17/53 10/59 + 10/66 9/28 18/39 − 6/43 19/59 20/62 21/41 − 7/37 11/34 21/47 − 7/57 12/37 3/24 + 5/25 14/43 23/59 − 3/47 15/46 16/49 17/58 + 2/59 19/58 15/51 + 2/59 23/43 − 7/34 6/24 + 2/25 23/59 − 3/51 30/59 − 9/51 36/51 − 22/59 8/24 10/30 13/39 14/42 17/51 18/54 19/57 22/66 29/47 − 15/53 9/24 − 1/25 9/46 + 8/57 33/57 − 15/62 25/62 − 3/46 21/62 20/59 18/53 6/25 + 3/30 16/47 22/46 − 7/51 14/41 25/62 − 3/49 13/38 37/57 − 15/49 14/54 + 5/59 20/58 15/24 − 7/25 18/41 − 4/43 17/49 7/38 + 7/43 16/46 31/59 − 11/62 Part of a Turn 0.3485 0.3488 0.3490 0.3500 0.3509 0.3510 0.3514 0.3519 0.3520 0.3529 0.3529 0.3530 0.3540 0.3548 0.3550 0.3559 0.3560 0.3570 0.3571 0.3571 0.3580 0.3585 0.3590 0.3600 0.3610 0.3617 0.3620 0.3621 0.3630 0.3636 0.3640 0.3650 0.3659 0.3660 0.3667 0.3670 0.3673 0.3680 0.3684 0.3684 0.3690 0.3696 0.3700 0.3704 0.3710 0.3720 0.3721 0.3725 0.3729 0.3730 0.3740 0.3750 0.3760 0.3770 0.3774 0.3780 0.3784 0.3788 0.3790 0.3793 0.3800 B&S, Becker, Hendey, K&T, & Rockford … 15/43 11/29 − 1/33 7/20 … 13/27 − 3/23 13/37 … 4/37 + 10/41 6/17 … 4/37 + 12/49 14/37 − 1/41 11/31 10/43 + 6/49 … 5/41 + 11/47 20/43 − 4/37 … … 14/37 − 1/49 … 14/39 22/47 − 4/37 9/23 − 1/33 17/47 15/27 − 6/31 … 23/49 − 5/47 12/33 26/47 − 7/37 28/47 − 9/39 … 10/17 − 4/18 … 5/27 + 6/33 18/49 16/31 − 4/27 7/19 … 30/49 − 9/37 … 30/47 − 11/41 10/27 32/49 − 11/39 2/29 + 10/33 16/43 … … 30/47 − 13/49 32/49 − 12/43 6/16 5/21 + 4/29 13/37 + 1/39 … 13/27 − 3/29 14/37 … 8/37 + 7/43 11/29 20/43 − 4/47 Copyright 2004, Industrial Press, Inc., New York, NY Cincinnati and LeBlond 23/66 15/43 2/47 + 19/62 6/24 + 3/30 20/57 25/53 − 7/58 13/37 19/54 24/62 − 2/57 12/34 18/51 31/59 − 10/58 22/59 − 1/53 22/62 12/25 − 3/24 21/59 12/49 + 6/54 20/43 − 4/37 10/28 15/42 38/62 − 13/51 19/53 14/39 9/25 18/46 − 2/66 17/47 17/41 − 2/38 21/58 25/53 − 5/46 24/66 25/62 − 2/51 3/24 + 6/25 15/41 13/57 + 8/58 11/30 13/49 + 6/59 18/49 31/66 − 6/59 14/38 21/57 21/62 + 2/66 17/46 6/24 + 3/25 20/54 23/62 34/57 − 11/49 16/43 19/51 22/59 21/49 − 3/54 5/46 + 13/49 9/24 11/49 + 10/66 20/51 − 1/66 20/53 31/53 − 12/58 14/37 25/66 8/37 + 7/43 22/58 7/25 + 3/30 Machinery's Handbook 27th Edition 1998 MILLING MACHINE INDEXING Table 3 (Continued) Accurate Angular Indexing Part of a Turn 0.3810 0.3810 0.3820 0.3824 0.3830 0.3830 0.3840 0.3846 0.3850 0.3860 0.3870 0.3871 0.3878 0.3880 0.3889 0.3890 0.3898 0.3900 0.3902 0.3910 0.3913 0.3920 0.3922 0.3929 0.3930 0.3939 0.3940 0.3947 0.3950 0.3953 0.3960 0.3962 0.3966 0.3970 0.3980 0.3990 0.4000 0.4000 0.4010 0.4020 0.4030 0.4032 0.4035 0.4040 0.4043 0.4048 0.4050 0.4054 0.4060 0.4068 0.4070 0.4074 0.4080 0.4082 0.4090 0.4091 0.4100 0.4103 0.4110 0.4118 0.4118 B&S, Becker, Hendey, K&T, & Rockford 8/21 19/47 − 1/43 25/49 − 5/39 … 18/47 27/43 − 12/49 27/43 − 10/41 15/39 15/37 − 1/49 1/37 + 14/39 3/17 + 4/19 12/31 19/49 14/41 + 2/43 7/18 17/41 − 1/39 … 2/23 + 10/33 16/41 14/31 − 2/33 9/23 14/33 − 1/31 … … 1/39 + 18/49 13/33 3/39 + 13/41 … 26/37 − 12/39 17/43 4/29 + 8/31 … … 25/41 − 10/47 3/16 + 4/19 7/39 + 9/41 6/15 8/20 2/37 + 17/49 5/43 + 14/49 26/49 − 6/47 … … 11/39 + 5/41 19/47 … 29/41 − 13/43 15/37 21/47 − 2/49 … 9/19 − 1/15 11/27 16/37 − 1/41 20/49 15/39 + 1/41 … 1/37 + 18/47 16/39 9/41 + 9/47 7/17 … Cincinnati and LeBlond 16/42 8/51 + 13/58 40/62 − 15/57 13/34 18/47 37/58 − 13/51 27/43 − 10/41 15/39 15/24 − 6/25 22/57 16/39 − 1/43 24/62 19/49 18/53 + 3/62 21/54 24/53 − 3/47 23/59 16/25 − 6/24 16/41 29/66 − 3/62 18/46 17/47 + 2/66 20/51 11/28 28/46 − 11/51 26/66 24/53 − 3/51 15/38 13/25 − 3/24 17/43 33/47 − 15/49 21/53 23/58 7/57 + 17/62 28/58 − 5/59 6/37 + 9/38 10/25 12/30 27/62 − 2/58 16/49 + 4/53 30/47 − 12/51 25/62 23/57 11/39 + 5/41 19/47 17/42 3/24 + 7/25 15/37 17/58 + 7/62 24/59 7/47 + 16/62 22/54 2/54 + 23/62 20/49 15/39 + 1/41 27/66 6/24 + 4/25 16/39 7/34 + 8/39 14/34 21/51 Part of a Turn 0.4120 0.4130 0.4138 0.4140 0.4146 0.4150 0.4151 0.4160 0.4167 0.4170 0.4180 0.4186 0.4190 0.4194 0.4200 0.4210 0.4211 0.4211 0.4220 0.4230 0.4237 0.4240 0.4242 0.4250 0.4255 0.4259 0.4260 0.4270 0.4280 0.4286 0.4286 0.4286 0.4290 0.4300 0.4310 0.4314 0.4320 0.4324 0.4330 0.4333 0.4340 0.4348 0.4350 0.4355 0.4359 0.4360 0.4370 0.4375 0.4380 0.4386 0.4390 0.4390 0.4394 0.4400 0.4407 0.4410 0.4412 0.4419 0.4420 0.4430 0.4440 B&S, Becker, Hendey, K&T, & Rockford 18/41 − 1/37 2/39 + 17/47 12/29 19/39 − 3/41 17/41 18/33 − 3/23 … 21/39 − 6/49 … 26/37 − 14/49 8/21 + 1/27 18/43 18/39 − 2/47 13/31 24/49 − 3/43 1/39 + 17/43 8/19 … 15/29 − 2/21 24/43 − 5/37 … 4/27 + 8/29 14/33 6/16 + 1/20 20/47 … 27/41 − 10/43 27/39 − 13/49 12/43 + 7/47 9/21 21/49 … 30/47 − 9/43 22/43 − 4/49 11/39 + 7/47 … 4/23 + 8/31 16/37 5/37 + 14/47 … 5/31 + 9/33 10/23 21/31 − 8/33 … … 6/31 + 8/33 27/39 − 12/47 7/16 13/27 − 1/23 … 18/43 + 1/49 18/41 … 8/41 + 12/49 … 10/37 + 7/41 … 19/43 18/33 − 3/29 4/39 + 16/47 9/41 + 11/49 Copyright 2004, Industrial Press, Inc., New York, NY Cincinnati and LeBlond 24/53 − 2/49 19/46 24/58 19/39 − 3/41 17/41 9/24 + 1/25 22/53 41/62 − 13/53 10/24 10/38 + 6/39 16/46 + 4/57 18/43 31/46 − 13/51 26/62 8/25 + 3/30 23/49 − 3/62 16/38 24/57 3/41 + 15/43 20/54 + 3/57 25/59 41/62 − 14/59 28/66 7/24 + 4/30 20/47 23/54 28/57 − 3/46 29/59 − 4/62 33/57 − 8/53 12/28 18/42 21/49 21/51 + 1/58 17/25 − 6/24 25/58 22/51 28/62 − 1/51 16/37 26/42 − 8/43 13/30 23/53 20/46 14/25 − 3/24 27/62 17/39 42/59 − 16/58 31/49 − 9/46 … 24/57 + 1/59 25/57 34/59 − 7/51 18/41 29/66 11/25 26/59 10/37 + 7/41 15/34 19/43 34/62 − 5/47 20/51 + 3/59 14/51 + 10/59 Machinery's Handbook 27th Edition MILLING MACHINE INDEXING 1999 Table 3 (Continued) Accurate Angular Indexing Part of a Turn 0.4444 0.4444 0.4450 0.4460 0.4468 0.4470 0.4474 0.4480 0.4483 0.4490 0.4490 0.4500 0.4510 0.4510 0.4516 0.4520 0.4524 0.4528 0.4530 0.4540 0.4545 0.4550 0.4560 0.4561 0.4565 0.4570 0.4576 0.4580 0.4583 0.4590 0.4595 0.4600 0.4610 0.4615 0.4620 0.4630 0.4630 0.4631 0.4634 0.4640 0.4643 0.4650 0.4651 0.4655 0.4660 0.4667 0.4670 0.4677 0.4680 0.4681 0.4690 0.4694 0.4697 0.4700 0.4706 0.4706 0.4710 0.4717 0.4720 0.4730 0.4737 B&S, Becker, Hendey, K&T, & Rockford 12/27 8/18 7/37 + 11/43 11/23 − 1/31 21/47 6/21 + 5/31 … 10/41 + 10/49 13/29 22/49 20/39 − 3/47 9/20 … 5/15 + 2/17 14/31 14/39 + 4/43 … … 3/23 + 10/31 14/27 − 2/31 15/33 25/47 − 3/39 9/37 + 10/47 … … 4/37 + 15/43 … 27/49 − 4/43 … 35/49 − 12/47 17/37 16/41 + 3/43 13/39 + 6/47 18/39 15/47 + 7/49 … … 9/21 + 1/29 19/41 21/43 − 1/41 … 21/37 − 4/39 20/43 … 13/41 + 7/47 7/15 19/37 − 2/43 … 11/27 + 2/33 22/47 8/23 + 4/33 23/49 … 19/29 − 5/27 8/17 … 12/39 + 8/49 … 20/39 − 2/49 6/39 + 15/47 9/19 Cincinnati and LeBlond 24/54 … 3/24 + 8/25 22/46 − 2/62 21/47 14/49 + 10/62 17/38 27/41 − 8/38 26/58 22/49 14/57 + 12/59 6/24 + 6/30 23/51 42/62 − 12/53 28/62 4/49 + 20/54 19/42 24/53 16/59 + 12/66 1/54 + 27/62 30/66 9/24 + 2/25 17/62 + 12/66 26/57 21/46 27/39 − 8/34 27/59 20/53 + 5/62 11/24 18/51 + 7/66 17/37 9/25 + 3/30 22/34 − 8/43 18/39 36/62 − 7/59 25/54 10/46 + 14/57 … 19/41 32/58 − 5/57 13/28 15/24 − 4/25 20/43 27/58 31/47 − 12/62 14/30 25/34 − 11/41 29/62 3/49 + 24/59 22/47 35/49 − 13/53 23/49 31/66 18/25 − 6/24 16/34 24/51 12/47 + 11/51 25/53 31/53 − 7/62 29/59 − 1/54 18/38 Part of a Turn 0.4737 0.4740 0.4746 0.4750 0.4760 0.4762 0.4770 0.4780 0.4783 0.4790 0.4800 0.4810 0.4815 0.4820 0.4828 0.4830 0.4839 0.4840 0.4848 0.4850 0.4860 0.4865 0.4870 0.4872 0.4878 0.4880 0.4884 0.4890 0.4894 0.4898 0.4900 0.4902 0.4906 0.4910 0.4912 0.4915 0.4920 0.4930 0.4940 0.4950 0.4960 0.4970 0.4980 0.4990 0.5000 0.5000 0.5000 0.5000 0.5000 0.5000 0.5000 0.5000 0.5000 0.5000 0.5000 0.5010 0.5020 0.5030 0.5040 0.5050 0.5060 B&S, Becker, Hendey, K&T, & Rockford … 9/37 + 9/39 … 6/16 + 2/20 4/43 + 18/47 10/21 26/43 − 6/47 12/31 + 3/33 11/23 22/39 − 4/47 16/39 + 3/43 14/41 + 6/43 13/27 33/49 − 9/47 14/29 27/39 − 9/43 15/31 5/37 + 15/43 16/33 24/47 − 1/39 13/43 + 9/49 18/37 15/37 + 4/49 19/39 20/41 8/29 + 7/33 21/43 28/43 − 6/37 23/47 24/49 13/21 − 4/31 … … 15/39 + 5/47 … … 25/37 − 9/49 8/41 + 14/47 33/49 − 7/39 5/29 + 10/31 8/23 + 4/27 33/47 − 8/39 20/37 − 2/47 26/41 − 5/37 8/16 9/18 10/20 … … … … … … … … 5/37 + 15/41 17/37 + 2/47 8/39 + 14/47 5/43 + 19/49 21/31 − 5/29 7/39 + 16/49 Copyright 2004, Industrial Press, Inc., New York, NY Cincinnati and LeBlond 27/57 9/34 + 9/43 28/59 9/24 + 3/30 15/53 + 11/57 20/42 30/47 − 10/62 24/62 + 6/66 22/46 10/53 + 18/62 12/25 22/58 + 6/59 26/54 19/46 + 4/58 28/58 27/39 − 9/43 30/62 24/46 − 2/53 32/66 3/24 + 9/25 43/62 − 11/53 18/37 26/43 − 4/34 19/39 20/41 5/46 + 22/58 21/43 19/47 + 5/59 23/47 24/49 6/24 + 6/25 25/51 26/53 21/46 + 2/58 28/57 29/59 17/46 + 6/49 21/53 + 6/62 14/46 + 11/58 9/24 + 3/25 20/53 + 7/59 7/46 + 20/58 29/41 − 9/43 26/41 − 5/37 12/24 14/28 15/30 17/34 19/38 21/42 23/46 27/54 29/58 31/62 33/66 37/51 − 11/49 25/53 + 2/66 16/49 + 9/51 37/66 − 3/53 15/24 − 3/25 22/53 + 6/66 Machinery's Handbook 27th Edition 2000 MILLING MACHINE INDEXING Table 3 (Continued) Accurate Angular Indexing Part of a Turn 0.5070 0.5080 0.5085 0.5088 0.5090 0.5094 0.5098 0.5100 0.5102 0.5106 0.5110 0.5116 0.5120 0.5122 0.5128 0.5130 0.5135 0.5140 0.5150 0.5152 0.5160 0.5161 0.5170 0.5172 0.5180 0.5185 0.5190 0.5200 0.5210 0.5217 0.5220 0.5230 0.5238 0.5240 0.5250 0.5254 0.5260 0.5263 0.5263 0.5270 0.5280 0.5283 0.5290 0.5294 0.5294 0.5300 0.5303 0.5306 0.5310 0.5319 0.5320 0.5323 0.5330 0.5333 0.5340 0.5345 0.5349 0.5350 0.5357 0.5360 0.5366 B&S, Becker, Hendey, K&T, & Rockford 33/47 − 8/41 12/37 + 9/49 … … 24/39 − 5/47 … … 8/21 + 4/31 25/49 24/47 6/37 + 15/43 22/43 21/29 − 7/33 21/41 20/39 22/37 − 4/49 19/37 30/43 − 9/49 1/39 + 23/47 17/33 28/43 − 5/37 16/31 13/39 + 9/49 15/29 9/47 + 16/49 14/27 27/41 − 6/43 3/41 + 21/47 17/39 + 4/47 12/23 19/31 − 3/33 17/43 + 6/47 11/21 29/47 − 4/43 6/16 + 3/20 … 28/37 − 9/39 10/19 … 32/47 − 6/39 19/39 + 2/49 … 18/37 + 2/47 9/17 … 5/27 + 10/29 … 26/49 15/23 − 4/33 25/47 7/27 + 9/33 … 18/37 + 2/43 8/15 28/41 − 7/47 … 23/43 16/37 + 4/39 … 1/41 + 22/43 22/41 Cincinnati and LeBlond 28/46 − 6/59 41/66 − 6/53 30/59 29/57 27/51 − 1/49 27/53 26/51 18/24 − 6/25 25/49 24/47 26/49 − 1/51 22/43 45/66 − 9/53 21/41 20/39 30/54 − 2/47 19/37 33/46 − 12/59 16/25 − 3/24 34/66 37/59 − 6/54 32/62 9/49 + 17/51 30/58 31/41 − 10/42 28/54 6/49 + 23/58 13/25 41/59 − 8/46 24/46 14/47 + 13/58 14/49 + 14/59 22/42 32/51 − 6/58 7/24 + 7/30 31/59 26/46 − 2/51 20/38 30/57 6/53 + 24/58 35/59 − 3/46 28/53 30/53 − 2/54 18/34 27/51 6/24 + 7/25 35/66 26/49 24/37 − 4/34 25/47 5/51 + 23/53 33/62 16/46 + 10/54 16/30 37/51 − 9/47 31/58 23/43 9/24 + 4/25 15/28 5/49 + 23/53 22/41 Part of a Turn 0.5370 0.5370 0.5371 0.5380 0.5385 0.5390 0.5400 0.5405 0.5410 0.5417 0.5420 0.5424 0.5430 0.5435 0.5439 0.5440 0.5450 0.5455 0.5460 0.5470 0.5472 0.5476 0.5480 0.5484 0.5490 0.5490 0.5500 0.5510 0.5510 0.5517 0.5520 0.5526 0.5530 0.5532 0.5540 0.5550 0.5556 0.5556 0.5560 0.5570 0.5580 0.5581 0.5588 0.5590 0.5593 0.5600 0.5606 0.5610 0.5610 0.5614 0.5620 0.5625 0.5630 0.5640 0.5641 0.5645 0.5650 0.5652 0.5660 0.5660 0.5667 B&S, Becker, Hendey, K&T, & Rockford … … 17/41 + 6/49 4/18 + 6/19 21/39 26/39 − 6/47 25/41 − 3/43 20/37 12/47 + 14/49 … 4/43 + 22/49 … 33/43 − 11/49 … … 4/37 + 17/39 3/39 + 22/47 18/33 13/27 + 2/31 21/31 − 3/23 … … 12/41 + 12/47 17/31 10/15 − 2/17 … 11/20 19/39 + 3/47 … 16/29 31/41 − 10/49 … 15/21 − 5/31 26/47 12/23 + 1/31 1/41 + 26/49 10/18 15/27 32/41 − 11/49 22/41 + 1/49 3/29 + 15/33 24/43 … 27/37 − 7/41 … 37/49 − 8/41 … 23/41 4/23 + 12/31 … 1/23 + 14/27 9/16 12/39 + 12/47 25/33 − 6/31 22/39 … 10/31 + 8/33 13/23 4/39 + 19/41 … … Copyright 2004, Industrial Press, Inc., New York, NY Cincinnati and LeBlond 29/54 6/51 + 26/62 … 12/49 + 17/58 21/39 34/51 − 6/47 6/25 + 9/30 20/37 2/38 + 21/43 13/24 7/46 + 23/59 32/59 22/54 + 8/59 25/46 31/57 4/37 + 17/39 15/24 − 2/25 36/66 2/34 + 19/39 32/49 − 7/66 29/53 23/42 25/39 − 4/43 34/62 8/47 + 25/66 28/51 6/24 + 9/30 31/53 − 2/59 27/49 32/58 29/46 − 4/51 21/38 28/54 + 2/58 26/47 12/53 + 19/58 17/25 − 3/24 30/54 … 35/47 − 10/53 18/49 + 11/58 7/53 + 23/54 24/43 19/34 43/59 − 9/53 33/59 14/25 37/66 23/41 5/51 + 25/54 32/57 9/34 + 11/37 … 22/46 + 5/59 41/49 − 18/66 22/39 35/62 3/24 + 11/25 26/46 9/46 + 20/54 30/53 17/30 Machinery's Handbook 27th Edition MILLING MACHINE INDEXING 2001 Table 3 (Continued) Accurate Angular Indexing Part of a Turn 0.5670 0.5676 0.5680 0.5686 0.5690 0.5690 0.5700 0.5710 0.5714 0.5714 0.5714 0.5720 0.5730 0.5740 0.5741 0.5745 0.5750 0.5758 0.5760 0.5763 0.5770 0.5780 0.5789 0.5789 0.5790 0.5800 0.5806 0.5810 0.5814 0.5820 0.5830 0.5833 0.5840 0.5849 0.5850 0.5854 0.5860 0.5862 0.5870 0.5870 0.5880 0.5882 0.5882 0.5890 0.5897 0.5900 0.5909 0.5910 0.5918 0.5920 0.5926 0.5930 0.5932 0.5940 0.5946 0.5950 0.5952 0.5957 0.5960 0.5965 0.5968 B&S, Becker, Hendey, K&T, & Rockford 33/47 − 5/37 21/37 23/31 − 4/23 … … 28/39 − 7/47 21/43 + 4/49 9/43 + 17/47 12/21 28/49 … 31/43 − 7/47 12/39 + 13/49 14/41 + 10/43 … 27/47 3/15 + 6/16 19/33 21/29 − 4/27 … 5/37 + 19/43 2/21 + 14/29 11/19 … 26/43 − 1/39 3/43 + 25/49 18/31 21/39 + 2/47 25/43 6/21 + 8/27 11/37 + 14/49 … 18/39 + 6/49 … 3/23 + 15/33 24/41 20/39 + 3/41 17/29 … 30/47 − 2/39 1/37 + 23/41 10/17 … 32/41 − 9/47 23/39 29/47 − 1/37 … 24/39 − 1/41 29/49 21/37 + 1/41 16/27 1/15 + 10/19 … 6/29 + 12/31 22/37 12/41 + 13/43 … 28/47 28/39 − 5/41 … … Cincinnati and LeBlond 25/47 + 2/57 21/37 21/47 + 8/66 29/51 33/58 42/59 − 7/49 6/24 + 8/25 39/57 − 6/53 16/28 24/42 28/49 40/58 − 6/51 23/57 + 10/59 23/37 − 2/42 31/54 27/47 9/24 + 6/30 38/66 24/49 + 5/58 34/59 32/46 − 7/59 25/49 + 4/59 22/38 33/57 38/62 − 2/59 12/25 + 3/30 36/62 18/53 + 14/58 25/43 23/38 − 1/43 8/46 + 27/66 14/24 13/57 + 21/59 31/53 15/24 − 1/25 24/41 17/54 + 16/59 34/58 27/46 37/53 − 6/54 28/57 + 6/62 20/34 30/51 8/46 + 22/53 23/39 18/24 − 4/25 39/66 40/59 − 4/46 29/49 21/34 − 1/39 32/54 22/34 − 2/37 35/59 15/49 + 19/66 22/37 18/25 − 3/24 25/42 28/47 15/51 + 16/53 34/57 37/62 Part of a Turn 0.5970 0.5980 0.5990 0.6000 0.6000 0.6010 0.6020 0.6030 0.6034 0.6038 0.6040 0.6047 0.6050 0.6053 0.6060 0.6061 0.6070 0.6071 0.6078 0.6080 0.6087 0.6090 0.6098 0.6100 0.6102 0.6110 0.6111 0.6120 0.6122 0.6129 0.6130 0.6140 0.6140 0.6150 0.6154 0.6160 0.6170 0.6170 0.6176 0.6180 0.6190 0.6190 0.6200 0.6207 0.6210 0.6212 0.6216 0.6220 0.6226 0.6230 0.6240 0.6250 0.6260 0.6270 0.6271 0.6275 0.6279 0.6280 0.6290 0.6290 0.6296 B&S, Becker, Hendey, K&T, & Rockford 6/47 + 23/49 35/49 − 5/43 17/37 + 6/43 9/15 12/20 32/41 − 7/39 13/16 − 4/19 16/41 + 10/47 … … 23/31 − 4/29 … 11/37 + 12/39 … 28/41 − 3/39 20/33 31/49 − 1/39 … … 1/31 + 19/33 14/23 17/31 + 2/33 25/41 23/33 − 2/23 … 1/39 + 24/41 … 27/41 − 2/43 30/49 19/31 15/19 − 3/17 25/39 − 1/37 … 22/37 + 1/49 24/39 10/41 + 16/43 12/37 + 12/41 29/47 … 5/39 + 24/49 1/43 + 28/47 13/21 23/43 + 4/47 … 29/37 − 7/43 … 23/37 14/27 + 3/29 … 24/37 − 1/39 5/29 + 14/31 10/16 12/43 + 17/49 17/47 + 13/49 … … 27/43 23/33 − 2/29 11/39 + 17/49 … 17/27 Copyright 2004, Industrial Press, Inc., New York, NY Cincinnati and LeBlond 13/58 + 22/59 16/47 + 17/66 23/49 + 7/54 15/25 18/30 32/41 − 7/39 20/47 + 9/51 24/49 + 6/53 35/58 32/53 21/58 + 15/62 26/43 3/24 + 12/25 23/38 29/54 + 4/58 40/66 23/47 + 6/51 17/28 31/51 24/53 + 9/58 28/46 40/59 − 4/58 25/41 6/24 + 9/25 36/59 5/28 + 16/37 33/54 29/39 − 5/38 30/49 38/62 1/49 + 32/54 36/49 − 7/58 35/57 9/24 + 6/25 24/39 14/53 + 19/54 5/59 + 33/62 29/47 21/34 3/53 + 32/57 17/53 + 17/57 26/42 8/25 + 9/30 36/58 6/46 + 26/53 41/66 23/37 15/53 + 20/59 33/53 24/37 − 1/39 4/49 + 32/59 15/24 21/46 + 10/59 24/46 + 6/57 37/59 32/51 27/43 28/47 + 2/62 12/54 + 24/59 39/62 34/54 Machinery's Handbook 27th Edition 2002 MILLING MACHINE INDEXING Table 3 (Continued) Accurate Angular Indexing Part of a Turn 0.6300 0.6304 0.6310 0.6316 0.6316 0.6320 0.6327 0.6330 0.6333 0.6340 0.6341 0.6350 0.6360 0.6364 0.6370 0.6379 0.6380 0.6383 0.6390 0.6400 0.6410 0.6410 0.6415 0.6420 0.6429 0.6429 0.6430 0.6440 0.6441 0.6450 0.6452 0.6460 0.6470 0.6471 0.6471 0.6480 0.6481 0.6486 0.6490 0.6491 0.6500 0.6510 0.6512 0.6515 0.6520 0.6522 0.6530 0.6531 0.6540 0.6550 0.6552 0.6560 0.6570 0.6579 0.6580 0.6585 0.6590 0.6596 0.6600 0.6604 0.6610 B&S, Becker, Hendey, K&T, & Rockford 11/41 + 17/47 … 9/37 + 19/49 12/19 … 12/37 + 12/39 31/49 13/27 + 5/33 … 7/17 + 4/18 26/41 9/39 + 19/47 7/37 + 21/47 21/33 5/47 + 26/49 … 12/27 + 6/31 30/47 14/23 + 1/33 4/37 + 25/47 … 25/39 … 23/37 + 1/49 … … 41/37 − 20/43 31/43 − 3/39 … 33/43 − 6/49 20/31 23/37 + 1/41 8/39 + 19/43 11/17 … 31/41 − 4/37 … 24/37 3/23 + 14/27 … 13/20 18/29 + 1/33 … … 8/31 + 13/33 15/23 24/31 − 4/33 32/49 23/41 + 4/43 23/31 − 2/23 19/29 29/41 − 2/39 10/23 + 6/27 … 10/21 + 6/33 27/41 15/27 + 3/29 31/47 8/47 + 24/49 … 2/41 + 30/49 Cincinnati and LeBlond 18/24 − 3/25 29/46 8/49 + 29/62 24/38 36/57 12/34 + 12/43 31/49 14/51 + 19/53 19/30 25/37 − 1/24 26/41 19/25 − 3/24 12/54 + 24/58 42/66 10/47 + 28/66 37/58 6/34 + 18/39 30/47 28/39 − 3/38 16/25 45/66 − 2/49 25/39 34/53 20/59 + 20/66 18/28 27/42 24/51 + 10/58 31/43 − 3/39 38/59 3/24 + 13/25 40/62 2/47 + 35/58 24/47 + 9/66 22/34 33/51 43/57 − 5/47 35/54 24/37 8/30 + 13/34 37/57 6/24 + 12/30 25/59 + 15/66 28/43 43/66 46/59 − 6/47 30/46 22/54 + 14/57 32/49 34/58 + 4/59 9/24 + 7/25 38/58 23/24 − 13/43 20/46 + 12/54 25/38 20/34 + 3/43 27/41 3/54 + 35/58 31/47 9/25 + 9/30 35/53 34/57 + 4/62 Part of a Turn 0.6610 0.6613 0.6620 0.6630 0.6640 0.6650 0.6660 0.6667 0.6667 0.6667 0.6667 0.6667 0.6667 0.6667 0.6667 0.6670 0.6680 0.6690 0.6700 0.6710 0.6720 0.6724 0.6730 0.6735 0.6739 0.6740 0.6744 0.6750 0.6757 0.6760 0.6765 0.6770 0.6774 0.6780 0.6780 0.6786 0.6790 0.6792 0.6800 0.6809 0.6810 0.6818 0.6820 0.6829 0.6830 0.6840 0.6842 0.6842 0.6850 0.6852 0.6860 0.6863 0.6870 0.6875 0.6880 0.6890 0.6897 0.6900 0.6905 0.6910 0.6920 B&S, Becker, Hendey, K&T, & Rockford … … 13/23 + 3/31 35/49 − 2/39 13/41 + 17/49 16/37 + 10/43 34/41 − 8/49 10/15 12/18 14/21 18/27 22/33 26/39 … … 24/41 + 4/49 14/41 + 16/49 5/23 + 14/31 37/49 − 4/47 9/21 + 8/33 15/41 + 15//49 … 7/43 + 25//49 33/49 … 4/39 + 28/49 29/43 10/16 + 1/20 25/37 20/23 − 6/31 … 7/37 + 20/41 21/31 … 21/39 + 6/43 … 7/37 + 24/49 … 31/47 + 1/49 32/47 21/27 − 3/31 … 15/37 + 13/47 28/41 5/17 + 7/18 31/37 − 6/39 13/19 … 15/41 + 15/47 … 3/23 + 15/27 … 28/37 − 3/43 11/16 13/21 + 2/29 36/47 − 3/39 20/29 21/37 + 6/49 … 35/49 − 1/43 35/43 − 5/41 Copyright 2004, Industrial Press, Inc., New York, NY Cincinnati and LeBlond 39/59 41/62 36/53 − 1/58 11/39 + 16/42 33/51 + 1/59 15/24 + 1/25 21/51 + 15/59 16/24 20/30 26/39 28/42 34/51 36/54 38/57 44/66 5/51 + 33/58 11/47 + 23/53 10/46 + 28/62 18/24 − 2/25 15/47 + 19/54 7/54 + 32//59 39/58 42/57 − 3//47 33/49 31/46 21/53 + 15/54 29/43 9/24 + 9/30 25/37 43/62 − 1/57 23/34 26/53 + 11/59 42/62 40/59 6/49 + 30/54 19/28 19/51 + 19/62 36/53 17/25 32/47 29/41 − 1/38 45/66 37/51 − 2/46 28/41 35/57 + 4/58 13/47 + 22/54 26/38 39/57 3/24 + 14/25 37/54 19/49 + 17/57 35/51 36/51 − 1/53 … 30/49 + 5/66 42/53 − 6/58 40/58 6/24 + 11/25 29/42 21/57 + 20/62 35/43 − 5/41 Machinery's Handbook 27th Edition MILLING MACHINE INDEXING 2003 Table 3 (Continued) Accurate Angular Indexing Part of a Turn 0.6923 0.6930 0.6935 0.6939 0.6940 0.6949 0.6950 0.6957 0.6960 0.6970 0.6970 0.6977 0.6980 0.6981 0.6990 0.7000 0.7010 0.7018 0.7020 0.7021 0.7027 0.7030 0.7037 0.7040 0.7050 0.7059 0.7059 0.7060 0.7069 0.7070 0.7073 0.7080 0.7083 0.7090 0.7097 0.7100 0.7105 0.7110 0.7119 0.7120 0.7121 0.7130 0.7140 0.7143 0.7143 0.7143 0.7150 0.7160 0.7170 0.7170 0.7174 0.7179 0.7180 0.7190 0.7193 0.7200 0.7209 0.7210 0.7220 0.7222 0.7230 B&S, Becker, Hendey, K&T, & Rockford 27/39 19/37 + 7/39 … 34/49 10/23 + 7/27 … 24/33 − 1/31 16/23 15/31 + 7/33 … 24/39 + 4/49 30/43 22/29 − 2/33 … 34/47 − 1/41 14/20 24/43 + 7/49 … 10/21 + 7/31 33/47 26/37 25/31 − 3/29 19/27 8/37 + 20/41 19/37 + 9/47 12/17 … 18/37 + 9/41 … 6/39 + 26/47 29/41 30/39 − 3/49 … 34/39 − 7/43 22/31 20/43 + 12/49 … 22/29 − 1/21 … 6/39 + 24/43 … 27/43 + 4/47 6/43 + 27/47 15/21 35/49 … 28/43 + 3/47 2/47 + 33/49 … 29/43 + 2/47 … 28/39 22/27 − 3/31 39/49 − 3/39 … 2/43 + 33/49 31/43 13/29 + 9/33 18/23 − 2/33 13/18 6/29 + 16/31 Cincinnati and LeBlond 27/39 19/37 + 7/39 43/62 34/49 14/38 + 14/43 41/59 9/24 + 8/25 32/46 32/47 + 1/66 46/66 24/51 + 12/53 30/43 4/47 + 38/62 37/53 14/58 + 27/59 21/30 28/47 + 6/57 40/57 7/37 + 20/39 33/47 26/37 23/58 + 19/62 38/54 47/59 − 5/54 15/24 + 2/25 24/34 36/51 38/58 + 3/59 41/58 7/30 + 18/38 29⁄41 13/58 + 30/62 17/24 31/46 + 2/57 44/62 18/24 − 1/25 27/38 33/39 − 5/37 42/59 31/54 + 8/58 47/66 17/30 + 6/41 45/57 − 4/53 20/28 30/42 35/49 21/25 − 3/24 25/51 + 14/62 38/53 28/59 + 16/66 33/46 28/39 21/58 + 21/59 12/57 + 30/59 41/57 18/25 31/43 21/47 + 17/62 13/46 + 29/66 39/54 11/46 + 30/62 Part of a Turn 0.7234 0.7240 0.7241 0.7250 0.7255 0.7258 0.7260 0.7270 0.7273 0.7280 0.7288 0.7290 0.7297 0.7300 0.7310 0.7317 0.7320 0.7330 0.7333 0.7340 0.7347 0.7350 0.7353 0.7358 0.7360 0.7368 0.7368 0.7370 0.7380 0.7381 0.7390 0.7391 0.7400 0.7407 0.7410 0.7414 0.7419 0.7420 0.7424 0.7430 0.7436 0.7440 0.7442 0.7447 0.7450 0.7451 0.7458 0.7460 0.7470 0.7480 0.7490 0.7500 0.7500 0.7510 0.7520 0.7530 0.7540 0.7544 0.7547 0.7550 0.7551 B&S, Becker, Hendey, K&T, & Rockford … 3/27 + 19/31 21/29 2/16 + 12/20 … … 34/41 − 6/47 15/19 − 1/16 24/33 23/37 + 5/47 … 38/49 − 2/43 27/37 11/27 + 10/31 15/37 + 14/43 30/41 20/37 + 9/47 19/37 + 9/41 11/15 6/21 + 13/29 36/49 29/37 − 2/41 … … 25/47 + 10/49 14/19 … 2/37 + 28/41 19/37 + 11/49 … 6/31 + 18/33 17/23 8/39 + 23/43 20/27 9/39 + 25/49 … 23/31 17/39 + 15/49 … 19/39 + 11/43 … 4/29 + 20/33 32/43 35/47 17/21 − 2/31 … … 13/47 + 23/49 23/41 + 8/43 19/43 + 15/49 13/15 − 2/17 12/16 15/20 11/23 + 9/33 19/23 − 2/27 23/39 + 8/49 6/37 + 29/49 … … 24/37 + 5/47 37/49 Copyright 2004, Industrial Press, Inc., New York, NY Cincinnati and LeBlond 34/47 34/41 − 4/38 42/58 7/24 + 13/30 37/51 45/62 2/49 + 37/54 14/54 + 29/62 48/66 23/49 + 15/58 43/59 12/47 + 27/57 27/37 6/24 + 12/25 26/59 + 18/62 30/41 26/57 + 16/58 39/47 − 6/62 22/30 26/49 + 12/59 36/49 9/24 + 9/25 25/34 39/53 47/59 − 4/66 28/38 42/57 13/49 + 25/53 31/47 + 4/51 31/42 12/62 + 36/66 34/46 6/25 + 15/30 40/54 49/57 − 7/59 43/58 46/62 28/51 + 11/57 49/66 1/53 + 42/58 29/39 27/49 + 11/57 32/43 35/47 15/24 + 3/25 38/51 44/59 2/59 + 47/66 29/49 + 9/58 10/53 + 33/59 36/47 − 1/59 18/24 21/28 39/53 + 1/66 39/57 + 4/59 11/53 + 36/66 25/46 + 12/57 43/57 40/53 21/24 − 3/25 37/49 Machinery's Handbook 27th Edition TABLE OF CONTENTS GEARS, SPLINES, AND CAMS WORM GEARING CHECKING GEAR SIZES 2095 2096 2098 2098 2098 Standard Design for Fine-pitch Formulas for Wormgears Materials for Worm Gearing Single-thread Worms Multi-thread Worms 2125 Checking Externall Spur Gear Sizes 2126 Measurement Over Wires 2130 Checking Internal Spur Gear 2139 Measurements for Checking Helical Gears using Wires 2140 Checking Spur Gear Size 2142 Formula for Chordal Dimension 2099 2099 2099 2100 2100 2103 Helical Gear Calculations Rules and Formulas Determining Direction of Thrust Determining Helix Angles Pitch of Cutter to be Used Shafts at Right Angles, Center Distance approx Shafts at Right Angles, Center Distance Exact Shafts at Any Angle, Center Distance Exact Selecting Cutter for Milling Helical Gears Factors for Selecting Cutters Outside and Pitch Diameters Milling the Helical Teeth Fine-Pitch Helical Gears Center Distance with no Backlash Change-gears for Hobbing Helical Gear Hobbing HELICAL GEARING 2104 2107 2108 2109 2109 2109 2110 2111 2112 2114 OTHER GEAR TYPES 2114 2114 2114 2114 2115 2115 2115 2115 2116 2119 2119 2120 2120 2121 2121 2122 2123 2124 Herringbone Gears General Classes of Problems Causes of Failures Elliptic Gears Planetary Gearing Direction of Rotation Compound Drive Planetary Bevel Gears Ratios of Epicyclic Gearing Ratchet Gearing Types of Ratchet Gearing Shape of Ratchet Wheel Teeth Pitch of Ratchet Wheel Teeth Module System Gear Design German Standard Tooth Form Tooth Dimensions Rules for Module System Equivalent Diametral Pitches, Circular Pitches GEAR MATERIALS 2144 2144 2144 2144 2144 2145 2145 2145 2145 2146 2146 2146 2146 2147 2147 2147 2149 2150 2150 2150 2151 2151 2151 2151 2152 2153 2153 2155 Gearing Material Classification of Gear Steels Use of Casehardening Steels Use of “Thru-Hardening” Steels Heat-Treatment for Machining Making Pinion Harder Forged and Rolled Carbon Steels Compositions Forged and Rolled Alloy Steels Compositions Steel Castings for Gears Compositions Effect of Alloying Metals Sintered Materials Steels for Industrial Gearing Bronze and Brass Gear Castings Materials for Worm Gearing Non-metallic Gears Power-Transmitting Capacity Safe Working Stresses Preferred Pitch Bore Sizes Preferred Pitches Keyway Stresses Invention of Gear Teeth Calculating Replacement Spur Gears Helical Gears SPLINES AND SERRATIONS 2156 Involute Splines 2156 American National Standard 2157 Terms 2158 Types of involute spline 2160 Tooth Proportions 2160 Symbols 2161 Formulas for Basic Dimensions 2162 Basic Dimensions 2162 Tooth Numbers 2027 Copyright 2004, Industrial Press, Inc., New York, NY Machinery's Handbook 27th Edition TABLE OF CONTENTS GEARS, SPLINES, AND CAMS SPLINES AND SERRATIONS CAMS AND CAM DESIGN (Continued) 2162 2162 2163 2164 2165 2165 2165 2166 2166 2167 2167 2167 2169 2169 2170 2171 2171 2172 2172 2172 2173 2174 2174 2175 2175 2176 2177 2177 2180 2180 2180 2181 2182 2182 2183 2184 2185 2186 Types and Classes of Fits Classes of Tolerances Maximum Tolerances Fillets and Chamfers Spline Variations Effect of Spline Variations Effective and Actual Dimensions Space Width and Tooth Thickness Limits Effective and Actual Dimensions Combinations of Spline Types Interchangeability Drawing Data Spline Data and Reference Dimensions Estimating Key and Spline Sizes Formulas for Torque Capacity Spline Application Factors Load Distribution Factors Fatigue-Life Factors Wear Life Factors Allowable Shear Stresses Crowned Splines for Large Misalignments Fretting Damage to Splines Inspection Methods Inspection with Gages Measurements with Pins Metric Module Splines Comparison of Symbols Formulas for Dimensions and Tolerances Tooth Thickness Modification Machining Tolerances Tooth Thickness Total Tolerance Selected Fit Classes Data Straight Splines British Standard Striaght Splines Splines Fittings Standard Splined Fittings Dimensions of Standard Splines Polygon-type Shaft Connections 2188 2188 2189 2194 2195 2197 2198 2200 2201 2203 2205 2210 2211 2211 2212 2213 Classes of Cams Cam Follower Systems Displacement Diagrams Cam Profile Determination Modified Constant Velocity Cam Pressure Angle and Radius of Curvature Cam Size for a Radial Follower Cam Size for Swinging Roller Follower Formulas for Calculating Pressure Angles Radius of Curvature Cam Forces, Contact Stresses, and Materials Calculation of Contact Stresses Layout of Cylinder Cams Shape of Rolls for Cylinder Cams Cam Milling Cutting Uniform Motion Cams 2028 Copyright 2004, Industrial Press, Inc., New York, NY Machinery's Handbook 27th Edition 2030 GEARING Axial thickness is the distance parallel to the axis between two pitch line elements of the same tooth Backlash is the shortest distance between the non-driving surfaces of adjacent teeth when the working flanks are in contact Base circle is the circle from which the involute tooth curve is generated or developed Base helix angle is the angle at the base cylinder of an involute gear that the tooth makes with the gear axis Base pitch is the circular pitch taken on the circumference of the base circles, or the distance along the line of action between two successive and corresponding involute tooth profiles The normal base pitch is the base pitch in the normal plane and the axial base pitch is the base pitch in the axial plane Base tooth thickness is the distance on the base circle in the plane of rotation between involutes of the same pitch Bottom land is the surface of the gear between the flanks of adjacent teeth Center distance is the shortest distance between the non-intersecting axes of mating gears, or between the parallel axes of spur gears and parallel helical gears, or the crossed axes of crossed helical gears or worm gears Central plane is the plane perpendicular to the gear axis in a worm gear, which contains the common perpendicular of the gear and the worm axes In the usual arrangement with the axes at right angles, it contains the worm axis Chordal addendum is the radial distance from the circular thickness chord to the top of the tooth, or the height from the top of the tooth to the chord subtending the circular thickness arc Chordal thickness is the length of the chord subtended by the circular thickness arc The dimension obtained when a gear tooth caliper is used to measure the tooth thickness at the pitch circle Circular pitch is the distance on the circumference of the pitch circle, in the plane of rotation, between corresponding points of adjacent teeth The length of the arc of the pitch circle between the centers or other corresponding points of adjacent teeth Circular thickness is the thickness of the tooth on the pitch circle in the plane of rotation, or the length of arc between the two sides of a gear tooth measured on the pitch circle Clearance is the radial distance between the top of a tooth and the bottom of a mating tooth space, or the amount by which the dedendum in a given gear exceeds the addendum of its mating gear Contact diameter is the smallest diameter on a gear tooth with which the mating gear makes contact Contact ratio is the ratio of the arc of action in the plane of rotation to the circular pitch, and is sometimes thought of as the average number of teeth in contact This ratio is obtained most directly as the ratio of the length of action to the base pitch Contact ratio – face is the ratio of the face advance to the circular pitch in helical gears Contact ratio – total is the ratio of the sum of the arc of action and the face advance to the circular pitch Contact stress is the maximum compressive stress within the contact area between mating gear tooth profiles Also called the Hertz stress Cycloid is the curve formed by the path of a point on a circle as it rolls along a straight line When such a circle rolls along the outside of another circle the curve is called an epicycloid, and when it rolls along the inside of another circle it is called a hypocycloid These curves are used in defining the former American Standard composite Tooth Form Dedendum is the radial or perpendicular distance between the pitch circle and the bottom of the tooth space Diametral pitch is the ratio of the number of teeth to the number of inches in the pitch diameter in the plane of rotation, or the number of gear teeth to each inch of pitch diameter Normal diametral pitch is the diametral pitch as calculated in the normal plane, or the diametral pitch divided by the cosine of the helix angle Copyright 2004, Industrial Press, Inc., New York, NY Machinery's Handbook 27th Edition GEARING 2031 Efficiency is the torque ratio of a gear set divided by its gear ratio Equivalent pitch radius is the radius of curvature of the pitch surface at the pitch point in a plane normal to the pitch line element Face advance is the distance on the pitch circle that a gear tooth travels from the time pitch point contact is made at one end of the tooth until pitch point contact is made at the other end Fillet radius is the radius of the concave portion of the tooth profile where it joins the bottom of the tooth space Fillet stress is the maximum tensile stress in the gear tooth fillet Flank of tooth is the surface between the pitch circle and the bottom land, including the gear tooth fillet Gear ratio is the ratio between the numbers of teeth in mating gears Helical overlap is the effective face width of a helical gear divided by the gear axial pitch Helix angle is the angle that a helical gear tooth makes with the gear axis at the pitch circle, unless specified otherwise Hertz stress, see Contact stress Highest point of single tooth contact (HPSTC) is the largest diameter on a spur gear at which a single tooth is in contact with the mating gear Interference is the contact between mating teeth at some point other than along the line of action Internal diameter is the diameter of a circle that coincides with the tops of the teeth of an internal gear Internal gear is a gear with teeth on the inner cylindrical surface Involute is the curve generally used as the profile of gear teeth The curve is the path of a point on a straight line as it rolls along a convex base curve, usually a circle Land The top land is the top surface of a gear tooth and the bottom land is the surface of the gear between the fillets of adjacent teeth Lead is the axial advance of the helix in one complete turn, or the distance along its own axis on one revolution if the gear were free to move axially Length of action is the distance on an involute line of action through which the point of contact moves during the action of the tooth profile Line of action is the portion of the common tangent to the base cylinders along which contact between mating involute teeth occurs Lowest point of single tooth contact (LPSTC) is the smallest diameter on a spur gear at which a single tooth is in contact with its mating gear Gear set contact stress is determined with a load placed on the pinion at this point Module is the ratio of the pitch diameter to the number of teeth, normally the ratio of pitch diameter in mm to the number of teeth Module in the inch system is the ratio of the pitch diameter in inches to the number of teeth Normal plane is a plane normal to the tooth surfaces at a point of contact and perpendicular to the pitch plane Number of teeth is the number of teeth contained in a gear Outside diameter is the diameter of the circle that contains the tops of the teeth of external gears Pitch is the distance between similar, equally-spaced tooth surfaces in a given direction along a given curve or line Pitch circle is the circle through the pitch point having its center at the gear axis Pitch diameter is the diameter of the pitch circle The operating pitch diameter is the pitch diameter at which the gear operates Pitch plane is the plane parallel to the axial plane and tangent to the pitch surfaces in any pair of gears In a single gear, the pitch plane may be any plane tangent to the pitch surfaces Pitch point is the intersection between the axes of the line of centers and the line of action Plane of rotation is any plane perpendicular to a gear axis Copyright 2004, Industrial Press, Inc., New York, NY Machinery's Handbook 27th Edition 2032 GEARING Pressure angle is the angle between a tooth profile and a radial line at its pitch point In involute teeth, the pressure angle is often described as the angle between the line of action and the line tangent to the pitch circle Standard pressure angles are established in connection with standard tooth proportions A given pair of involute profiles will transmit smooth motion at the same velocity ratio when the center distance is changed Changes in center distance in gear design and gear manufacturing operations may cause changes in pitch diameter, pitch and pressure angle in the same gears under different conditions Unless otherwise specified, the pressure angle is the standard pressure angle at the standard pitch diameter The operating pressure angle is determined by the center distance at which a pair of gears operate In oblique teeth such as helical and spiral designs, the pressure angle is specified in the transverse, normal or axial planes Principle reference planes are pitch plane, axial plane and transverse plane, all intersecting at a point and mutually perpendicular Rack: A rack is a gear with teeth spaced along a straight line, suitable for straight line motion A basic rack is a rack that is adopted as the basis of a system of interchangeable gears Standard gear tooth dimensions are often illustrated on an outline of a basic rack Roll angle is the angle subtended at the center of a base circle from the origin of an involute to the point of tangency of a point on a straight line from any point on the same involute The radian measure of this angle is the tangent of the pressure angle of the point on the involute Root diameter is the diameter of the circle that contains the roots or bottoms of the tooth spaces Tangent plane is a plane tangent to the tooth surfaces at a point or line of contact Tip relief is an arbitrary modification of a tooth profile where a small amount of material is removed from the involute face of the tooth surface near the tip of the gear tooth Tooth face is the surface between the pitch line element and the tooth tip Tooth surface is the total tooth area including the flank of the tooth and the tooth face Total face width is the dimensional width of a gear blank and may exceed the effective face width as with a double-helical gear where the total face width includes any distance separating the right-hand and left-hand helical gear teeth Transverse plane is a plane that is perpendicular to the axial plane and to the pitch plane In gears with parallel axes, the transverse plane and the plane of rotation coincide Trochoid is the curve formed by the path of a point on the extension of a radius of a circle as it rolls along a curve or line A trochoid is also the curve formed by the path of a point on a perpendicular to a straight line as the straight line rolls along the convex side of a base curve By the first definition, a trochoid is derived from the cycloid, by the second definition it is derived from the involute True involute form diameter is the smallest diameter on the tooth at which the point of tangency of the involute tooth profile exists Usually this position is the point of tangency of the involute tooth profile and the fillet curve, and is often referred to as the TIF diameter Undercut is a condition in generated gear teeth when any part of the fillet curve lies inside a line drawn at a tangent to the working profile at its lowest point Undercut may be introduced deliberately to facilitate shaving operations, as in pre-shaving Whole depth is the total depth of a tooth space, equal to the addendum plus the dedendum and equal to the working depth plus clearance Working depth is the depth of engagement of two gears, or the sum of their addendums The standard working distance is the depth to which a tooth extends into the tooth space of a mating gear when the center distance is standard Definitions of gear terms are given in AGMA Standards 112.05, 115.01, and 116.01 entitled “Terms, Definitions, Symbols and Abbreviations,” “Reference Information—Basic Gear Geometry,” and “Glossary—Terms Used in Gearing,” respectively; obtainable from American Gear Manufacturers Assn., 500 Montgomery St., St., Alexandria, VA 22314 Copyright 2004, Industrial Press, Inc., New York, NY Machinery's Handbook 27th Edition SPUR GEARING 2037 American National Standard and Former American Standard Gear Tooth Forms ANSI B6.1-1968, (R1974) and ASA B6.1-1932 Basic Rack of the 20-Degree and 25-Degree Full-Depth Involute Systems Basic Rack of the 141⁄2-Degree Full-Depth Involute System Basic Rack of the 20-Degree Stub Involute System Approximation of Basic Rack for the 141⁄2-Degree Composite System Copyright 2004, Industrial Press, Inc., New York, NY Machinery's Handbook 27th Edition SPUR GEARING 2043 Gears for Given Center Distance and Ratio.—When it is necessary to use a pair of gears of given ratio at a specified center distance C1, it may be found that no gears of standard diametral pitch will satisfy the center distance requirement Gears of standard diametral pitch P may need to be redesigned to operate at other than their standard pitch diameter D and standard pressure angle φ The diametral pitch P1 at which these gears will operate is NP + NG P 1 = -2C 1 (1) where Np =number of teeth in pinion NG =number of teeth in gear and their operating pressure angle φ1 is P1 (2) φ 1 = arccos ⎛ - cos φ⎞ ⎝P ⎠ Thus although the pair of gears are cut to a diametral pitch P and a pressure angle φ, they operate as standard gears of diametral pitch P1 and pressure angle φ1 The pitch P and pressure angle φ should be chosen so that φ1 lies between about 18 and 25 degrees The operating pitch diameters of the pinion Dp1 and of the gear DG1 are NP D P1 = -P1 (3a) NG D G1 = -P1 and (3b) The base diameters of the pinion DPB1 and of the gear DGB1 are D PB1 = D P1 cos φ 1 and (4a) D GB1 = D G1 cos φ 1 (4b) The basic tooth thickness, t1, at the operating pitch diameter for both pinion and gear is 1.5708 t 1 = P1 (5) The root diameters of the pinion DPR1 and gear DGR1 and the corresponding outside diameters DPO1 and DGO1 are not standard because each gear is to be cut with a cutter that is not standard for the operating pitch diameters DP1 and DG1 The root diameters are NP D PR 1 = – 2b P 1 P where (6a) and NG D GR 1 = – 2b G 1 P t P 2 – 1.5708 ⁄ P b P 1 = b c – ⎛ ⎞ ⎝ ⎠ 2 tan φ t G 2 – 1.5708 ⁄ P b G 1 = b c – 2 tan φ where bc is the hob or cutter addendum for the pinion and gear The tooth thicknesses of the pinion tP2 and the gear tG2 are and N P 1.5708 t P 2 = ⎛ - + inv φ 1 – inv φ⎞ ⎠ P ⎝ NP Copyright 2004, Industrial Press, Inc., New York, NY (6b) (7a) (7b) (8a) Machinery's Handbook 27th Edition 2044 SPUR GEARING N G 1.5708 t G 2 = ⎛ - + inv φ 1 – inv φ⎞ ⎠ P ⎝ NG (8b) The outside diameter of the pinion DPO and the gear DGO are D PO = 2 × C 1 – D GR 1 – 2 ( b c – 1 ⁄ P ) and (9a) D GO = 2 × C 1 – D PR 1 – 2 ( b c – 1 ⁄ P ) (9b) Example:Design gears of 8 diametral pitch, 20-degree pressure angle, and 28 and 88 teeth to operate at 7.50-inch center distance The gears are to be cut with a hob of 0.169inch addendum 28 + 88 P 1 = - = 7.7333 2 × 7.50 (1) 7.7333 φ 1 = arccos ⎛ - × 0.93969⎞ = 24.719° ⎝ 8 ⎠ (2) 28 D P1 = - = 3.6207 in 7.7333 and (3a) 88 D G1 = - = 11.3794 in 7.7333 (3b) D PB1 = 3.6207 × 0.90837 = 3.2889 in and (4a) D GB1 = 11.3794 × 0.90837 = 10.3367 in (4b) 1.5708 t 1 = - = 0.20312 in 7.7333 (5) D PR1 = 28 – 2 × 0.1016 = 3.2968 in 8 and (6a) D GR1 = 88 – 2 × ( – 0.0428 ) = 11.0856 in 8 (6b) 0.2454 – 1.5708 ⁄ 8 b P1 = 0.169 – ⎛ -⎞ = 0.1016 in ⎝ 2 × 0.36397 ⎠ (7a) b G1 = 0.169 – ⎛ 0.3505 – 1.5708 ⁄ 8⎞ = – 0.0428 in ⎝ -⎠ 2 × 0.36397 (7b) 28 1.5708 t P2 = - ⎛ - + 0.028922 – 0.014904⎞ = 0.2454 in ⎠ 8 ⎝ 28 (8a) t G2 = 88 ⎛ 1.5708 + 0.028922 – 0.014904⎞ – 0.3505 in - ⎝ ⎠ 88 8 (8b) D PO1 = 2 × 7.50 – 11.0856 – 2 ( 0.169 – 1 ⁄ 8 ) = 3.8264 in (9a) D GO1 = 2 × 7.50 – 3.2968 – 2 ( 0.169 – 1 ⁄ 8 ) = 11.6152 in (9b) Copyright 2004, Industrial Press, Inc., New York, NY Machinery's Handbook 27th Edition 2046 SPUR GEARING The tooth thickness on the pitch circle can be determined very accurately by means of measurement over wires which are located in tooth spaces that are diametrically opposite or as nearly diametrically opposite as possible Where measurement over wires is not feasible, the circular or arc tooth thickness can be used in determining the chordal thickness which is the dimension measured with a gear tooth caliper Circular Thickness of Tooth when Outside Diameter has been Enlarged.—When the outside diameter of a small pinion is not standard but is enlarged to avoid undercut and to improve tooth action, the teeth are located farther out radially relative to the standard pitch diameter and consequently the circular tooth thickness at the standard pitch diameter is increased To find this increased arc thickness the following formula is used, where t = tooth thickness; e = amount outside diameter is increased over standard; φ = pressure angle; and p = circular pitch at the standard pitch diameter p t = + e tan φ 2 Example:The outside diameter of a pinion having 10 teeth of 5 diametral pitch and a pressure angle of 141⁄2 degrees is to be increased by 0.2746 inch The circular pitch equivalent to 5 diametral pitch is 0.6283 inch Find the arc tooth thickness at the standard pitch diameter t = 0.6283 + ( 0.2746 × tan 14 1⁄2 ° ) 2 t = 0.3142 + ( 0.2746 × 0.25862 ) = 0.3852 inch Circular Thickness of Tooth when Outside Diameter has been Reduced.—If the outside diameter of a gear is reduced, as is frequently done to maintain the standard center distance when the outside diameter of the mating pinion is increased, the circular thickness of the gear teeth at the standard pitch diameter will be reduced.This decreased circular thickness can be found by the following formula where t = circular thickness at the standard pitch diameter; e = amount outside diameter is reduced under standard; φ = pressure angle; and p = circular pitch t = p – e tan φ -2 Example:The outside diameter of a gear having a pressure angle of 141⁄2 degrees is to be reduced by 0.2746 inch or an amount equal to the increase in diameter of its mating pinion The circular pitch is 0.6283 inch Determine the circular tooth thickness at the standard pitch diameter t = 0.6283 – ( 0.2746 × tan 14 1⁄2 ° ) 2 t = 0.3142 – ( 0.2746 × 0.25862 ) = 0.2432 inch Chordal Thickness of Tooth when Outside Diameter is Standard.—T o f i n d t h e chordal or straight line thickness of a gear tooth the following formula can be used where tc = chordal thickness; D = pitch diameter; and N = number of teeth t c = D sin ⎛ 90°⎞ ⎝ ⎠ N Example:A pinion has 15 teeth of 3 diametral pitch; the pitch diameter is equal to 15 ÷ 3 or 5 inches Find the chordal thickness at the standard pitch diameter t c = 5 sin ⎛ 90°⎞ = 5 sin 6° = 5 × 0.10453 = 0.5226 inch -⎝ 15 ⎠ Copyright 2004, Industrial Press, Inc., New York, NY Machinery's Handbook 27th Edition SPUR GEARING 2047 Chordal Thicknesses and Chordal Addenda of Milled, Full-depth Gear Teeth and of Gear Milling Cutters 1 11⁄2 2 21⁄2 3 31⁄2 4 5 6 7 8 9 10 11 12 14 16 18 20 Dimension Diametral Pitch T =chordal thickness of gear tooth and cutter tooth at pitch line; H =chordal addendum for full-depth gear tooth; A =chordal addendum of cutter = (2.157 ÷ diametral pitch) − H = (0.6866 × circular pitch) − H Number of Gear Cutter, and Corresponding Number of Teeth No 1 135 Teeth No 2 55 Teeth No 3 35 Teeth No 4 26 Teeth No 5 21 Teeth No 6 17 Teeth No 7 14 Teeth No 8 12 Teeth 1.5663 T 1.5707 1.5706 1.5702 1.5698 1.5694 1.5686 1.5675 H 1.0047 1.0112 1.0176 1.0237 1.0294 1.0362 1.0440 1.0514 T 1.0471 1.0470 1.0468 1.0465 1.0462 1.0457 1.0450 1.0442 H 0.6698 0.6741 0.6784 0.6824 0.6862 0.6908 0.6960 0.7009 T 0.7853 0.7853 0.7851 0.7849 0.7847 0.7843 0.7837 0.7831 H 0.5023 0.5056 0.5088 0.5118 0.5147 0.5181 0.5220 0.5257 T 0.6283 0.6282 0.6281 0.6279 0.6277 0.6274 0.6270 0.6265 H 0.4018 0.4044 0.4070 0.4094 0.4117 0.4144 0.4176 0.4205 T 0.5235 0.5235 0.5234 0.5232 0.5231 0.5228 0.5225 0.5221 H 0.3349 0.3370 0.3392 0.3412 0.3431 0.3454 0.3480 0.3504 T 0.4487 0.4487 0.4486 0.4485 0.4484 0.4481 0.4478 0.4475 H 0.2870 0.2889 0.2907 0.2919 0.2935 0.2954 0.2977 0.3004 T 0.3926 0.3926 0.3926 0.3924 0.3923 0.3921 0.3919 0.3915 H 0.2511 0.2528 0.2544 0.2559 0.2573 0.2590 0.2610 0.2628 T 0.3141 0.3141 0.3140 0.3139 0.3138 0.3137 0.3135 0.3132 H 0.2009 0.2022 0.2035 0.2047 0.2058 0.2072 0.2088 0.2102 T 0.2618 0.2617 0.2617 0.2616 0.2615 0.2614 0.2612 0.2610 H 0.1674 0.1685 0.1696 0.1706 0.1715 0.1727 0.1740 0.1752 T 0.2244 0.2243 0.2243 0.2242 0.2242 0.2240 0.2239 0.2237 H 0.1435 0.1444 0.1453 0.1462 0.1470 0.1480 0.1491 0.1502 T 0.1963 0.1963 0.1962 0.1962 0.1961 0.1960 0.1959 0.1958 H 0.1255 0.1264 0.1272 0.1279 0.1286 0.1295 0.1305 0.1314 T 0.1745 0.1745 0.1744 0.1744 0.1743 0.1743 0.1741 0.1740 H 0.1116 0.1123 0.1130 0.1137 0.1143 0.1151 0.1160 0.1168 T 0.1570 0.1570 0.1570 0.1569 0.1569 0.1568 0.1567 0.1566 H 0.1004 0.1011 0.1017 0.1023 0.1029 0.1036 0.1044 0.1051 T 0.1428 0.1428 0.1427 0.1427 0.1426 0.1426 0.1425 0.1424 H 0.0913 0.0919 0.0925 0.0930 0.0935 0.0942 0.0949 0.0955 T 0.1309 0.1309 0.1308 0.1308 0.1308 0.1307 0.1306 0.1305 H 0.0837 0.0842 0.0848 0.0853 0.0857 0.0863 0.0870 0.0876 T 0.1122 0.1122 0.1121 0.1121 0.1121 0.1120 0.1119 0.1118 H 0.0717 0.0722 0.0726 0.0731 0.0735 0.0740 0.0745 0.0751 T 0.0981 0.0981 0.0981 0.0981 0.0980 0.0980 0.0979 0.0979 H 0.0628 0.0632 0.0636 0.0639 0.0643 0.0647 0.0652 0.0657 T 0.0872 0.0872 0.0872 0.0872 0.0872 0.0871 0.0870 0.0870 H 0.0558 0.0561 0.0565 0.0568 0.0571 0.0575 0.0580 0.0584 T 0.0785 0.0785 0.0785 0.0785 0.0784 0.0784 0.0783 0.0783 H 0.0502 0.0505 0.0508 0.0511 0.0514 0.0518 0.0522 0.0525 Copyright 2004, Industrial Press, Inc., New York, NY Machinery's Handbook 27th Edition 2048 SPUR GEARING 1⁄ 4 5⁄ 16 8⁄ 8 7⁄ 16 1⁄ 2 9⁄ 16 5⁄ 8 11⁄ 16 3⁄ 4 13⁄ 16 7⁄ 8 15⁄ 16 1 11⁄8 11⁄4 18⁄8 11⁄2 13⁄4 2 21⁄4 21⁄2 3 Number of Gear Cutter, and Corresponding Number of Teeth Dimension Circular Pitch Chordal Thicknesses and Chordal Addenda of Milled, Full-depth Gear Teeth and of Gear Milling Cutters No 1 135 Teeth No 2 55 Teeth No 3 35 Teeth No 4 26 Teeth No 5 21 Teeth No 6 17 Teeth No 7 14 Teeth No 8 12 Teeth T H T H 0.1250 0.0799 0.1562 0.0999 0.1250 0.0804 0.1562 0.1006 0.1249 0.0809 0.1562 0.1012 0.1249 0.0814 0.1561 0.1018 0.1249 0.0819 0.1561 0.1023 0.1248 0.0824 0.1560 0.1030 0.1247 0.0830 0.1559 0.1038 0.1246 0.0836 0.1558 0.1045 T H T H 0.1875 0.1199 0.2187 0.1399 0.1875 0.1207 0.2187 0.1408 0.1874 0.1214 0.2186 0.1416 0.1873 0.1221 0.2186 0.1425 0.1873 0.1228 0.2185 0.1433 0.1872 0.1236 0.2184 0.1443 0.1871 0.1245 0.2183 0.1453 0.1870 0.1254 0.2181 0.1464 T H T H 0.2500 0.1599 0.2812 0.1799 0.2500 0.1609 0.2812 0.1810 0.2499 0.1619 0.2811 0.1821 0.2498 0.1629 0.2810 0.1832 0.2498 0.1638 0.2810 0.1842 0.2496 0.1649 0.2808 0.1855 0.2495 0.1661 0.2806 0.1868 0.2493 0.1673 0.2804 0.1882 T H T H 0.3125 0.1998 0.3437 0.2198 0.3125 0.2012 0.3437 0.2213 0.3123 0.2023 0.3436 0.2226 0.3123 0.2036 0.3435 0.2239 0.3122 0.2047 0.3434 0.2252 0.3120 0.2061 0.3432 0.2267 0.3118 0.2076 0.3430 0.2283 0.3116 0.2091 0.3427 0.2300 T H T H 0.3750 0.2398 0.4062 0.2598 0.3750 0.2414 0.4062 0.2615 0.3748 0.2428 0.4060 0.2631 0.3747 0.2443 0.4059 0.2647 0.3747 0.2457 0.4059 0.2661 0.3744 0.2473 0.4056 0.2679 0.3742 0.2491 0.4054 0.2699 0.3740 0.2509 0.4050 0.2718 T H T H 0.4375 0.2798 0.4687 0.2998 0.4375 0.2816 0.4687 0.3018 0.4373 0.2833 0.4685 0.3035 0.4372 0.2850 0.4684 0.3054 0.4371 0.2866 0.4683 0.3071 0.4368 0.2885 0.4680 0.3092 0.4366 0.2906 0.4678 0.3114 0.4362 0.2927 0.4674 0.3137 T H T H 0.5000 0.3198 0.5625 0.3597 0.5000 0.3219 0.5625 0.3621 0.4998 0.3238 0.5623 0.3642 0.4997 0.3258 0.5621 0.3665 0.4996 0.3276 0.5620 0.3685 0.4993 0.3298 0.5617 0.3710 0.4990 0.3322 0.5613 0.3737 0.4986 0.3346 0.5610 0.3764 T H T H 0.6250 0.3997 0.6875 0.4397 0.6250 0.4023 0.6875 0.4426 0.6247 0.4047 0.6872 0.4452 0.6246 0.4072 0.6870 0.4479 0.6245 0.4095 0.6869 0.4504 0.6241 0.4122 0.6865 0.4534 0.6237 0.4152 0.6861 0.4567 0.6232 0.4182 0.6856 0.4600 T H T H 0.7500 0.4797 0.8750 0.5596 0.7500 0.4828 0.8750 0.5633 0.7497 0.4857 0.8746 0.5666 0.7495 0.4887 0.8744 0.5701 0.7494 0.4914 0.8743 0.5733 0.7489 0.4947 0.8737 0.5771 0.7485 0.4983 0.8732 0.5813 0.7480 0.5019 0.8726 0.5855 T H T H 1.0000 0.6396 1.1250 0.7195 1.0000 0.6438 1.1250 0.7242 0.9996 0.6476 1.1246 0.7285 0.9994 0.6516 1.1242 0.7330 0.9992 0.6552 1.1240 0.7371 0.9986 0.6596 1.1234 0.7420 0.9980 0.6644 1.1226 0.7474 0.9972 0.6692 1.1220 0.7528 T H T H 1.2500 0.7995 1.5000 0.9594 1.2500 0.8047 1.5000 0.9657 1.2494 0.8095 1.4994 0.9714 1.2492 0.8145 1.4990 0.9774 1.2490 0.8190 1.4990 0.9828 1.2482 0.8245 1.4978 0.9894 1.2474 0.8305 1.4970 0.9966 1.2464 0.8365 1.4960 1.0038 Copyright 2004, Industrial Press, Inc., New York, NY Machinery's Handbook 27th Edition SPUR GEARING 2053 Circular Pitch in Gears—Pitch Diameters, Outside Diameters, and Root Diameters 1⁄ 16 Pitch Diameter Corresponding to Factor for Number of Teeth 1.9099 1.7507 1.5915 1.4324 1.2732 1.1141 0.9549 0.7958 0.6366 0.5968 0.5570 0.5173 0.4775 0.4576 0.4377 0.4178 0.3979 0.3780 0.3581 0.3382 0.3183 0.2984 0.2785 0.2586 0.2387 0.2188 0.2122 0.1989 0.1790 0.1592 0.1393 0.1194 0.1061 0.0995 0.0796 0.0597 0.0398 0.0199 3.8197 3.5014 3.1831 2.8648 2.5465 2.2282 1.9099 1.5915 1.2732 1.1937 1.1141 1.0345 0.9549 0.9151 0.8754 0.8356 0.7958 0.7560 0.7162 0.6764 0.6366 0.5968 0.5570 0.5173 0.4475 0.4377 0.4244 0.3979 0.3581 0.3183 0.2785 0.2387 0.2122 0.1989 0.1592 0.1194 0.0796 0.0398 5.7296 5.2521 4.7746 4.2972 3.8197 3.3422 2.8648 2.3873 1.9099 1.7905 1.6711 1.5518 1.4324 1.3727 1.3130 1.2533 1.1937 1.1340 1.0743 1.0146 0.9549 0.8952 0.8356 0.7759 0.7162 0.6565 0.6366 0.5968 0.5371 0.4775 0.4178 0.3581 0.3183 0.2984 0.2387 0.1790 0.1194 0.0597 7.6394 7.0028 6.3662 5.7296 5.0929 4.4563 3.8197 3.1831 2.5465 2.3873 2.2282 2.0690 1.9099 1.8303 1.7507 1.6711 1.5915 1.5120 1.4324 1.3528 1.2732 1.1937 1.1141 1.0345 0.9549 0.8754 0.8488 0.7958 0.7162 0.6366 0.5570 0.4775 0.4244 0.3979 0.3183 0.2387 0.1592 0.0796 9.5493 8.7535 7.9577 7.1620 6.3662 5.5704 4.7746 3.9789 3.1831 2.9841 2.7852 2.5863 2.3873 2.2878 2.1884 2.0889 1.9894 1.8900 1.7905 1.6910 1.5915 1.4921 1.3926 1.2931 1.1937 1.0942 1.0610 0.9947 0.8952 0.7958 0.6963 0.5968 0.5305 0.4974 0.3979 0.2984 0.1989 0.0995 11.4591 10.5042 9.5493 8.5943 7.6394 6.6845 5.7296 4.7746 3.8197 3.5810 3.3422 3.1035 2.8648 2.7454 2.6261 2.5067 2.3873 2.2680 2.1486 2.0292 1.9099 1.7905 1.6711 1.5518 1.4324 1.3130 1.2732 1.1937 1.0743 0.9549 0.8356 0.7162 0.6366 0.5968 0.4775 0.3581 0.2387 0.1194 13.3690 12.2549 11.1408 10.0267 8.9127 7.7986 6.6845 5.5704 4.4563 4.1778 3.8993 3.6208 3.3422 3.2030 3.0637 2.9245 2.7852 2.6459 2.5067 2.3674 2.2282 2.0889 1.9496 1.8104 1.6711 1.5319 1.4854 1.3926 1.2533 1.1141 0.9748 0.8356 0.7427 0.6963 0.5570 0.4178 0.2785 0.1393 15.2788 14.0056 12.7324 11.4591 10.1859 8.9127 7.6394 6.3662 5.0929 4.7746 4.4563 4.1380 3.8197 3.6606 3.5014 3.3422 3.1831 3.0239 2.8648 2.7056 2.5465 2.3873 2.2282 2.0690 1.9099 1.7507 1.6977 1.5915 1.4324 1.2732 1.1141 0.9549 0.8488 0.7958 0.6366 0.4775 0.3183 0.1592 17.1887 15.7563 14.3239 12.8915 11.4591 10.0267 8.5943 7.1620 5.7296 5.3715 5.0134 4.6553 4.2972 4.1181 3.9391 3.7600 3.5810 3.4019 3.2229 3.0438 2.8648 2.6857 2.5067 2.3276 2.1486 1.9695 1.9099 1.7905 1.6114 1.4324 1.2533 1.0743 0.9549 0.8952 0.7162 0.5371 0.3581 0.1790 Root Diameter Factor 6 51⁄2 5 41⁄2 4 31⁄2 3 21⁄2 2 17⁄8 13⁄4 15⁄8 11⁄2 17⁄16 13⁄8 15⁄16 11⁄4 13⁄16 11⁄8 11⁄16 1 15⁄ 16 7⁄ 8 13⁄ 16 3⁄ 4 11⁄ 16 2⁄ 3 5⁄ 8 9⁄ 16 1⁄ 2 7⁄ 16 3⁄ 8 1⁄ 3 5⁄ 16 1⁄ 4 3⁄ 16 1⁄ 8 Outside Dia Factor Circular Pitch in Inches For any particular circular pitch and number of teeth, use the table as shown in the example to find the pitch diameter, outside diameter, and root diameter Example: Pitch diameter for 57 teeth of 6-inch circular pitch = 10 × pitch diameter given under factor for 5 teeth plus pitch diameter given under factor for 7 teeth (10 × 9.5493) + 13.3690 = 108.862 inches Outside diameter of gear equals pitch diameter plus outside diameter factor from next-to-last column in table = 108.862 + 3.8197 = 112.682 inches Root diameter of gear equals pitch diameter minus root diameter factor from last column in table = 108.862 − 4.4194 = 104.443 inches Factor for Number of Teeth 1 2 3 4 5 6 7 8 9 3.8197 3.5014 3.1831 2.8648 2.5465 2.2282 1.9099 1.5915 1.2732 1.1937 1.1141 1.0345 0.9549 0.9151 0.8754 0.8356 0.7958 0.7560 0.7162 0.6764 0.6366 0.5968 0.5570 0.5173 0.4775 0.4377 0.4244 0.3979 0.3581 0.3183 0.2785 0.2387 0.2122 0.1989 0.1592 0.1194 0.0796 0.0398 4.4194 4.0511 3.6828 3.3146 2.9463 2.5780 2.2097 1.8414 1.4731 1.3811 1.2890 1.1969 1.1049 1.0588 1.0128 0.9667 0.9207 0.8747 0.8286 0.7826 0.7366 0.6905 O.6445 0.5985 0.5524 0.5064 0.4910 0.4604 0.4143 0.3683 0.3222 0.2762 0.2455 0.2302 0.1841 0.1381 0.0921 0.0460 tially in increasing the addendum and hence the outside diameter of the pinion and decreasing the addendum and hence the outside diameter of the mating gear These changes in outside diameters of pinion and gear do not change the velocity ratio or the procedures in cutting the teeth on a hobbing machine or generating type of shaper or planer Data in Table 7 on page 2050 are taken from ANSI Standard B6.1-1968, reaffirmed 1974, and show for 20-degree and 25-degree full-depth standard tooth forms, respectively, the addendums and tooth thicknesses for long addendum pinions and their mating short Copyright 2004, Industrial Press, Inc., New York, NY Machinery's Handbook 27th Edition Table 9d Tooth Proportions Recommended for Enlarging Fine-Pitch Pinions of 25-Degree Pressure Angle— 20 Diametral Pitch and Finer ANSI B6.7-1977, Information Sheet B Enlarged C.D System Pinion Mating with Standard Gear Enlarged Pinion Dimensions Outside Diameter, DoP Addendum, aP Basic Tooth Thickness, tP 6 7 8 9 10 11 12 13 14 15 8.7645 9.7253 10.6735 11.6203 12.5691 13.5039 14.3588 15.2138 16.0686 17.0000 1.3822 1.3626 1.3368 1.3102 1.2846 1.2520 1.1794 1.1069 1.0343 1.0000 2.18362 2.10029 2.01701 1.94110 1.87345 1.80579 1.73813 1.67047 1.60281 1.57030 Contact Ratio Two Equal Pinions Contact Ratio with a 15-Tooth Gear 0.5829 0.6722 0.7616 0.8427 0.9155 0.9880 1.0606 1.1331 1.2057 1.2400 0.696 0.800 0.904 1.003 1.095 1.183 1.231 1.279 1.328 1.358 0.954 1.026 1.094 1.156 1.211 1.261 1.290 1.317 1.343 1.358 Addendum, aG Basic Tooth Thickness, tG Dedendum Based on 20 Pitch, b bG Recommended Minimum No of Teeth, N Contact Ratio n Mating with N 0.3429 0.4322 0.5216 0.6029 0.6755 0.7480 0.8206 0.8931 0.9657 1.0000 0.95797 1.04130 1.12459 1.20048 1.26814 1.33581 1.40346 1.47112 1.53878 1.57080 1.8971 1.8078 1.7184 1.6371 1.5645 1.4920 1.4194 1.3469 1.2743 1.2400 24 23 22 20 19 18 17 16 15 15 1.030 1.108 1.177 1.234 1.282 1.322 1.337 1.347 1.352 1.358 a Caution should be exercised in the use of pinions above the horizontal lines They should be checked for suitability, particularly in the areas of contact ratio (less than 1.2 is not recommended), center distance, clearance, and tooth strength b The actual dedendum is calculated by dividing the values in this column by the desired diametral pitch and then adding to the result an amount ∆ found in Table 9a As an example, a 20-degree pressure angle 7-tooth pinion meshing with a 42-tooth gear would have, for 24 diametral pitch, a dedendum of 0.4565 ÷ 24 + 0.0004 = 0.0194 The 42-tooth gear would have a dedendum of 2.0235 ÷ 24 + 0.004 = 0.0847 inch SPUR GEARING Number of Teeth,a n Dedendum Based on 20 Pitch, Dedendum Based on 20 Pitch, b bP Standard Center Distance (Long and Short Addendums) Reduced Gear Dimensions All dimensions are given in inches All values are for 1 diametral pitch For any other sizes of teeth, all linear dimensions should be divided by the diametral pitch Copyright 2004, Industrial Press, Inc., New York, NY 2057 Note: The tables in the ANSI B6.7-1977 standard also specify Form Diameter, Roll Angle to Form Diameter, and Top Land These are not shown here The top land is in no case less than 0.275/P The form diameters and the roll angles to form diameter shown in the Standard are the values which should be met with a standard hob when generating the tooth thicknesses shown in the tables These form diameters provides more than enough length of involute profile for any mating gear smaller than a rack However,since these form diameters are based on gear tooth generation using standard hobs, they should impose little or no hardship on manufacture except in cases of the most critical quality levels In such cases, form diameter specifications and master gear design should be based upon actual mating conditions Machinery's Handbook 27th Edition SPUR GEARING 2063 1) Pinion contact diameter, dc 31 × 0.93969 cos A = 3.3 × 10 = 0.88274 A = 28°1′30″ (1) tan b = 0.36397 – 31 ( 0.53227 – 0.36397 ) 23 = 0.13713 b = 7°48′26″ (2) 23 × 0.93969 d c = 10 × 0.99073 = 2.1815 inches (3) cos a = 23 × 0.93963 2.5 × 10 = 0.86452 a = 30°10′20″ (4) tan B = 0.36397 – 23 ( 0.58136 – 0.36937 ) 31 = 0.20267 B = 11°27′26″ (5) 31 × 0.93969 D c = 10 × 0.98000 = 2.9725 inches (6) 31 m f = ( 0.53227 – 0.20267 ) 6.28318 = 1.626 (7a) 23 m f = ( 0.58136 – 0.13713 ) 6.28318 = 1.626 (7b) 6.28318 tan c = 0.58136 – -23 = 0.30818 c = 17°7′41″ (8) 23 × 0.93969 d L = 10 × 0.95565 = 2.2616 inches (9) 6.28318 tan C = 0.53227 – -31 = 0.32959 C = 18°14′30″ (10) 31 × 0.93969 D L = 10 × 0.94974 = 3.0672 inches (11) 2) Gear contact diameter, Dc 3) Contact ratio, mf 4) Pinion LPSTC, dL 5) Gear LPSTC, DL Copyright 2004, Industrial Press, Inc., New York, NY Machinery's Handbook 27th Edition 2066 GEAR DATA FOR DRAWINGS 9) Maximum calculated circular thickness on the standard pitch circle is the tooth thickness which will provide the desired minimum backlash when the gear is assembled in mesh with its mate on minimum center distance Control may best be exerted by testing in tight mesh with a master which integrates all errors in the several teeth in mesh through the arc of action as explained on page 2073 This value is independent of the effect of runout a) Maximum calculated normal circular thickness is the circular tooth thickness in the normal plane which satisfies requirements explained in (9) 10) Gear testing radius is the distance from its axis of rotation to the standard pitch line of a standard master when in intimate contact under recommended pressure on a variablecenter-distance running gage Maximum testing radius should be calculated to provide the maximum circular tooth thickness specified in (9) when checked as explained on page 2073 This value is affected by the runout of the gear Tolerance on testing radius must be equal to or greater than the total composite error permitted by the quality class specified in (11) 11) Quality class is specified for convenience when talking or writing about the accuracy of the gear 12) Maximum total composite error, and 13) Maximum tooth-to-tooth composite error Actual tolerance values (12 and 13) permitted by the quality class (11) are specified in inches to provide machine operator or inspector with tolerances required to inspect the gear 14) Testing pressure recommendations are given on page 2073 Incorrect testing pressure will result in incorrect measurement of testing radius 15) Master specifications by tool or code number may be required to call for the use of a special master gear when tooth thickness deviates excessively from standard 16) Measurement over two 0.xxxx diameter pins may be specified to assist the manufacturing department in determining size at machine for setup only 17) Outside diameter is usually shown on the drawing of the gear together with other blank dimensions so that it will not be necessary for machine operators to search gear tooth data for this dimension Since outside diameter is also frequently used in the manufacture and inspection of the teeth, it may be included in the data block with other tooth specifications if preferred To permit use of topping hobs for cutting gears on which the tooth thickness has been modified from standard, the outside diameter should be related to the specified gear testing radius (10) 18) Maximum root diameter is specified to assure adequate clearance for the outside diameter of the mating gear This dimension is usually considered acceptable if the gear is checked with a master and meets specifications (10) through (13) 19) Active profile diameter of a gear is the smallest diameter at which the mating gear tooth profile can make contact Because of difficulties involved in checking, this specification is not recommended for gears finer than 48 pitch 20) Surface roughness on active profile surfaces may be specified in microinches to be checked by instrument up to about 32 pitch, or by visual comparison in the finer pitch ranges It is difficult to determine accurately the surface roughness of fine pitch gears For many commercial applications surface roughness may be considered acceptable on gears which meet the maximum tooth-to-tooth-error specification (13) 21) Mating gear part number may be shown as a convenient reference If the gear is used in several applications, all mating gears may be listed but usual practice is to record this information in a reference file 22) Number of teeth in mating gear, and 23) Minimum operating center distance This information is often specified to eliminate the necessity of getting prints of the mating gear and assemblies for checking the design specifications, interference, backlash, determination of master gear specification, and acceptance or rejection of gears made out of tolerance Copyright 2004, Industrial Press, Inc., New York, NY ... 31 6 31 7 31 8 31 9 32 0 32 1 32 2 32 3 32 4 32 5 32 6 32 7 32 8 32 9 33 0 33 1 33 2 33 3 33 4 33 5 33 6 33 7 33 8 33 9 34 0 34 1 34 2 34 3 34 4 34 5 34 6 34 7 34 8 34 9 35 0 35 1 35 2 35 3 35 4 35 5 35 6 35 7 35 8 35 9 36 0 36 1 36 2 36 3 36 4... 0 .32 90 0 .33 00 0 .33 10 0 .33 20 0 .33 30 0 .33 33 0 .33 33 0 .33 33 0 .33 33 0 .33 33 0 .33 33 0 .33 33 0 .33 33 0 .33 40 0 .33 50 0 .33 60 0 .33 70 0 .33 80 0 .33 87 0 .33 90 0 .33 96 0 .34 00 0 .34 04 0 .34 10 0 .34 15 0 .34 20 0 .34 21 0 .34 30... + 35 /58 31 /47 9/25 + 9 /30 35 / 53 34/57 + 4 /62 Part of a Turn 0 .66 10 0 .66 13 0 .66 20 0 .6 630 0 .66 40 0 .66 50 0 .66 60 0 .66 67 0 .66 67 0 .66 67 0 .66 67 0 .66 67 0 .66 67 0 .66 67 0 .66 67 0 .66 70 0 .66 80 0 .66 90 0 .67 00