Contact Us

Ohio Drill & Tool Company
23255 Georgetown Rd.

P.O. Box 154 
Homeworth, OH 44634
(330) 525-7717

(800) 826-5237
Fax: (330) 525-5432

 

Half Round Drills Left And Right Hand

Half round drills have become widely used in the screw machine industry.  They are designed for quick penetration in brass and other free machining metals.  These drills provide greater chip clearance, which is desirable in deep hole drilling.  This tool will provide a very smooth finish in many applications.  118 deg. standard drill point.

Fractional Sizes
catalog page: 35
Size Left Hand # Decimal Equivalent Overall Length Flute Length
1/64 625001 .0156 3/4 3/16
1/32 625002 .0313 1-3/8 1/2
3/64 625003 .0469 1-3/4 3/4
1/16 625004 .0625 1-7/8 7/8
5/64 625005 .0781 2 1
3/32 625006 .0938 2-1/4 1-1/4
7/64 625007 .1094 2-5/8 1-1/2
1/8 625008 .1250 2-3/4 1-5/8
9/64 625009 .1406 2-7/8 1-3/4
5/32 625010 .1563 3-1/8 2
11/64 625011 .1719 3-1/4 2-1/8
3/16 625012 .1875 3-1/2 2-5/16
13/64 625013 .2031 3-5/8 2-7/16
7/32 625014 .2188 3-3/4 2-1/2
15/64 625015 .2344 3-7/8 2-5/8
1/4 625016 .2500 4 2-3/4
17/64 625017 .2656 4-1/8 2-7/8
9/32 625018 .2813 4-1/4 2-15/16
19/64 625019 .2969 4-3/8 3-1/16
5/16 625020 .3125 4-1/2 3-3/16
21/64 625021 .3281 4-5/8 3-5/16
11/32 625022 .3438 4-3/4 3-7/16
23/64 625023 .3594 4-7/8 3-1/2
3/8 625024 .3750 5 3-5/8
25/64 625025 .3906 5-1/8 3-3/4
13/32 625026 .4063 5-1/4 3-7/8
27/64 625027 .4219 5-3/8 3-15/16
7/16 625028 .4375 5-1/2 4-1/16
29/64 625029 .4531 5-5/8 4-3/16
15/32 625030 .4688 5-3/4 4-5/16
31/64 625031 .4844 5-7/8 4-3/8
1/2 625032 .5000 6 4-1/2
33/64 625033 .5156 6 4
17/32 625034 .5312 6 4
35/64 625035 .5469 6 4
9/16 625036 .5625 6 4
37/64 625037 .5781 6 4
19/32 625038 .5938 6 4
39/64 625039 .6094 6 4
5/8 625040 .6250 6 4
41/64 625041 .6406 6 4
21/32 625042 .6562 6 4
43/64 625043 .6719 6 4
11/16 625044 .6875 6 4
45/64 625045 .7031 6 4
23/32 625046 .7188 6 4
47/64 625047 .7344 6 4
3/4 625048 .7500 6 4
49/64 625049 .7656 6 4
25/32 625050 .7812 6 4
51/64 625051 .7969 6 4
13/16 625052 .8125 6 4
53/64 625053 .8281 6 4
27/32 625054 .8438 6 4
55/64 625055 .8594 6 4
7/8 625056 .8750 6 4
57/64 625057 .8906 6 4
29/32 625058 .9062 6 4
59/64 625059 .9219 6 4
15/16 625060 .9375 6 4
61/64 625061 .9531 6 4
31/32 625062 .9688 6 4
63/64 625063 .9844 6 4
1 inch 625064 1.0000 6 4
Fractional Sizes
catalog page: 35
Size Right Hand # Decimal Equivalent Overall Length Flute Length
1/64 525001 .0156 3/4 3/16
1/32 525002 .0313 1-3/8 1/2
3/64 525003 .0469 1-3/4 3/4
1/16 525004 .0625 1-7/8 7/8
5/64 525005 .0781 2 1
3/32 525006 .0938 2-1/4 1-1/4
7/64 525007 .1094 2-5/8 1-1/2
1/8 525008 .1250 2-3/4 1-5/8
9/64 525009 .1406 2-7/8 1-3/4
5/32 525010 .1563 3-1/8 2
11/64 525011 .1719 3-1/4 2-1/8
3/16 525012 .1875 3-1/2 2-5/16
13/64 525013 .2031 3-5/8 2-7/16
7/32 525014 .2188 3-3/4 2-1/2
15/64 525015 .2344 3-7/8 2-5/8
1/4 525016 .2500 4 2-3/4
17/64 525017 .2656 4-1/8 2-7/8
9/32 525018 .2813 4-1/4 2-15/16
19/64 525019 .2969 4-3/8 3-1/16
5/16 525020 .3125 4-1/2 3-3/16
21/64 525021 .3281 4-5/8 3-5/16
11/32 525022 .3438 4-3/4 3-7/16
23/64 525023 .3594 4-7/8 3-1/2
3/8 525024 .3750 5 3-5/8
25/64 525025 .3906 5-1/8 3-3/4
13/32 525026 .4063 5-1/4 3-7/8
27/64 525027 .4219 5-3/8 3-15/16
7/16 525028 .4375 5-1/2 4-1/16
29/64 525029 .4531 5-5/8 4-3/16
15/32 525030 .4688 5-3/4 4-5/16
31/64 525031 .4844 5-7/8 4-3/8
1/2 525032 .5000 6 4-1/2
33/64 525033 .5156 6 4
17/32 525034 .5312 6 4
35/64 525035 .5469 6 4
9/16 525036 .5625 6 4
37/64 525037 .5781 6 4
19/32 525038 .5938 6 4
39/64 525039 .6094 6 4
5/8 525040 .6250 6 4
41/64 525041 .6406 6 4
21/32 525042 .6562 6 4
43/64 525043 .6719 6 4
11/16 525044 .6875 6 4
45/64 525045 .7031 6 4
23/32 525046 .7188 6 4
47/64 525047 .7344 6 4
3/4 525048 .7500 6 4
49/64 525049 .7656 6 4
25/32 525050 .7812 6 4
51/64 525051 .7969 6 4
13/16 525052 .8125 6 4
53/64 525053 .8281 6 4
27/32 525054 .8438 6 4
55/64 525055 .8594 6 4
7/8 525056 .8750 6 4
57/64 525057 .8906 6 4
29/32 525058 .9062 6 4
59/64 525059 .9219 6 4
15/16 525060 .9375 6 4
61/64 525061 .9531 6 4
31/32 525062 .9688 6 4
63/64 525063 .9844 6 4
1 inch 525064 1.0000 6 4
Letter Sizes
catalog page: 35
Size Left Hand # Decimal Equivalent Overall Length Flute Length
A 627901 .2340 3-7/8 2-5/8
B 627902 .2380 4 2-3/4
C 627903 .2420 4 2-3/4
D 627904 .2460 4 2-3/4
E 627905 .2500 4 2-3/4
F 627906 .2570 4-1/8 2-7/8
G 627907 .2610 4-1/8 2-7/8
H 627908 .2660 4-1/8 2-7/8
I 627909 .2720 4-1/8 2-7/8
J 627910 .2770 4-1/8 2-7/8
K 627911 .2810 4-1/4 2-15/16
L 627912 .2900 4-1/4 2-15/16
M 627913 .2950 4-3/8 3-1/16
N 627914 .3020 4-3/8 3-1/16
O 627915 .3160 4-1/2 3-3/16
P 627916 .3230 4-5/8 3-5/16
Q 627917 .3320 4-3/4 3-7/16
R 627918 .3390 4-3/4 3-7/16
S 627919 .3480 4-7/8 3-1/2
T 627920 .3580 4-7/8 3-1/2
U 627921 .3680 5 3-5/8
V 627922 .3770 5 3-5/8
W 627923 .3860 5-1/8 3-3/4
X 627924 .3970 5-1/8 3-3/4
Y 627925 .4040 5-1/4 3-7/8
Z 627926 .4130 5-1/4 3-7/8
Letter Sizes
catalog page: 35
Size Right Hand # Decimal Equivalent Overall Length Flute Length
A 527901 .2340 3-7/8 2-5/8
B 527902 .2380 4 2-3/4
C 527903 .2420 4 2-3/4
D 527904 .2460 4 2-3/4
E 527905 .2500 4 2-3/4
F 527906 .2570 4-1/8 2-7/8
G 527907 .2610 4-1/8 2-7/8
H 527908 .2660 4-1/8 2-7/8
I 527909 .2720 4-1/8 2-7/8
J 527910 .2770 4-1/8 2-7/8
K 527911 .2810 4-1/4 2-15/16
L 527912 .2900 4-1/4 2-15/16
M 527913 .2950 4-3/8 3-1/16
N 527914 .3020 4-3/8 3-1/16
O 527915 .3160 4-1/2 3-3/16
P 527916 .3230 4-5/8 3-5/16
Q 527917 .3320 4-3/4 3-7/16
R 527918 .3390 4-3/4 3-7/16
S 527919 .3480 4-7/8 3-1/2
T 527920 .3580 4-7/8 3-1/2
U 527921 .3680 5 3-5/8
V 527922 .3770 5 3-5/8
W 527923 .3860 5-1/8 3-3/4
X 527924 .3970 5-1/8 3-3/4
Y 527925 .4040 5-1/4 3-7/8
Z 527926 .4130 5-1/4 3-7/8
Wire Gauge Sizes
catalog page: 36
Size Left Hand # Decimal Equivalent Overall Length Flute Length
1 626801 .2280 3-7/8 2-5/8
2 626802 .2210 3-7/8 2-5/8
3 626803 .2130 3-3/4 2-1/2
4 626804 .2090 3-3/4 2-1/2
5 626805 .2055 3-3/4 2-1/2
6 626806 .2040 3-3/4 2-1/2
7 626807 .2010 3-5/8 2-7/16
8 626808 .1990 3-5/8 2-7/16
9 626809 .1960 3-5/8 2-7/16
10 626810 .1935 3-5/8 2-7/16
11 626811 .1910 3-1/2 2-5/16
12 626812 .1890 3-1/2 2-5/16
13 626813 .1850 3-1/2 2-5/16
14 626814 .1820 3-3/8 2-3/16
15 626815 .1800 3-3/8 2-3/16
16 626816 .1770 3-3/8 2-3/16
17 626817 .1730 3-3/8 2-3/16
18 626818 .1695 3-1/4 2-1/8
19 626819 .1660 3-1/4 2-1/8
20 626820 .1610 3-1/4 2-1/8
21 626821 .1590 3-1/4 2-1/8
22 626822 .1570 3-1/8 2
23 626823 .1540 3-1/8 2
24 626824 .1520 3-1/8 2
25 626825 .1495 3 1-7/8
26 626826 .1470 3 1-7/8
27 626827 .1440 3 1-7/8
28 626828 .1405 2-7/8 1-3/4
29 626829 .1360 2-7/8 1-3/4
30 626830 .1285 2-3/4 1-5/8
31 626831 .1200 2-3/4 1-5/8
32 626832 .1160 2-3/4 1-5/8
33 626833 .1130 2-5/8 1-1/2
34 626834 .1110 2-5/8 1-1/2
35 626835 .1100 2-5/8 1-1/2
36 626836 .1065 2-1/2 1-7/16
37 626837 .1040 2-1/2 1-7/16
38 626838 .1015 2-1/2 1-7/16
39 626839 .0995 2-3/8 1-3/8
40 626840 .0980 2-3/8 1-3/8
41 626841 .0960 2-3/8 1-3/8
42 626842 .0935 2-1/4 1-1/4
43 626843 .0890 2-1/4 1-1/4
44 626844 .0860 2-1/8 1-1/8
45 626845 .0820 2-1/8 1-1/8
46 626846 .0810 2-1/8 1-1/8
47 626847 .0785 2 1
48 626848 .0760 2 1
49 626849 .0730 2 1
50 626850 .0700 2 1
51 626851 .0670 2 1
52 626852 .0635 1-7/8 7/8
53 626853 .0595 1-7/8 7/8
54 626854 .0550 1-7/8 7/8
55 626855 .0520 1-7/8 7/8
56 626856 .0465 1-3/4 3/4
57 626857 .0430 1-3/4 3/4
58 626858 .0420 1-5/8 11/16
59 626859 .0410 1-5/8 11/16
60 626860 .0400 1-5/8 11/16
61 626861 .0390 1-5/8 11/16
62 626862 .0380 1-1/2 5/8
63 626863 .0370 1-1/2 5/8
64 626864 .0360 1-1/2 5/8
65 626865 .0350 1-1/2 5/8
66 626866 .0330 1-3/8 1/2
67 626867 .0320 1-3/8 1/2
68 626868 .0310 1-3/8 1/2
69 626869 .0292 1-3/8 1/2
70 626870 .0280 1-1/4 3/8
71 626871 .0260 1-1/4 3/8
72 626872 .0250 1-1/8 5/16
73 626873 .0240 1-1/8 5/16
74 626874 .0225 1 1/4
75 626875 .0210 1 1/4
76 626876 .0200 7/8 3/16
77 626877 .0180 7/8 3/16
78 626878 .0160 7/8 3/16
79 626879 .0145 3/4 3/16
80 626880 .0135 3/4 3/16
Wire Gauge Sizes
catalog page: 36
Size Right Hand # Decimal Equivalent Overall Length Flute Length
1 526801 .2280 3-7/8 2-5/8
2 526802 .2210 3-7/8 2-5/8
3 526803 .2130 3-3/4 2-1/2
4 526804 .2090 3-3/4 2-1/2
5 526805 .2055 3-3/4 2-1/2
6 526806 .2040 3-3/4 2-1/2
7 526807 .2010 3-5/8 2-7/16
8 526808 .1990 3-5/8 2-7/16
9 526809 .1960 3-5/8 2-7/16
10 526810 .1935 3-5/8 2-7/16
11 526811 .1910 3-1/2 2-5/16
12 526812 .1890 3-1/2 2-5/16
13 526813 .1850 3-1/2 2-5/16
14 526814 .1820 3-3/8 2-3/16
15 526815 .1800 3-3/8 2-3/16
16 526816 .1770 3-3/8 2-3/16
17 526817 .1730 3-3/8 2-3/16
18 526818 .1695 3-1/4 2-1/8
19 526819 .1660 3-1/4 2-1/8
20 526820 .1610 3-1/4 2-1/8
21 526821 .1590 3-1/4 2-1/8
22 526822 .1570 3-1/8 2
23 526823 .1540 3-1/8 2
24 526824 .1520 3-1/8 2
25 526825 .1495 3 1-7/8
26 526826 .1470 3 1-7/8
27 526827 .1440 3 1-7/8
28 526828 .1405 2-7/8 1-3/4
29 526829 .1360 2-7/8 1-3/4
30 526830 .1285 2-3/4 1-5/8
31 526831 .1200 2-3/4 1-5/8
32 526832 .1160 2-3/4 1-5/8
33 526833 .1130 2-5/8 1-1/2
34 526834 .1110 2-5/8 1-1/2
35 526835 .1100 2-5/8 1-1/2
36 526836 .1065 2-1/2 1-7/16
37 526837 .1040 2-1/2 1-7/16
38 526838 .1015 2-1/2 1-7/16
39 526839 .0995 2-3/8 1-3/8
40 526840 .0980 2-3/8 1-3/8
41 526841 .0960 2-3/8 1-3/8
42 526842 .0935 2-1/4 1-1/4
43 526843 .0890 2-1/4 1-1/4
44 526844 .0860 2-1/8 1-1/8
45 526845 .0820 2-1/8 1-1/8
46 526846 .0810 2-1/8 1-1/8
47 526847 .0785 2 1
48 526848 .0760 2 1
49 526849 .0730 2 1
50 526850 .0700 2 1
51 526851 .0670 2 1
52 526852 .0635 1-7/8 7/8
53 526853 .0595 1-7/8 7/8
54 526854 .0550 1-7/8 7/8
55 526855 .0520 1-7/8 7/8
56 526856 .0465 1-3/4 3/4
57 526857 .0430 1-3/4 3/4
58 526858 .0420 1-5/8 11/16
59 526859 .0410 1-5/8 11/16
60 526860 .0400 1-5/8 11/16
61 526861 .0390 1-5/8 11/16
62 526862 .0380 1-1/2 5/8
63 526863 .0370 1-1/2 5/8
64 526864 .0360 1-1/2 5/8
65 526865 .0350 1-1/2 5/8
66 526866 .0330 1-3/8 1/2
67 526867 .0320 1-3/8 1/2
68 526868 .0310 1-3/8 1/2
69 526869 .0292 1-3/8 1/2
70 526870 .0280 1-1/4 3/8
71 526871 .0260 1-1/4 3/8
72 526872 .0250 1-1/8 5/16
73 526873 .0240 1-1/8 5/16
74 526874 .0225 1 1/4
75 526875 .0210 1 1/4
76 526876 .0200 7/8 3/16
77 526877 .0180 7/8 3/16
78 526878 .0160 7/8 3/16
79 526879 .0145 3/4 3/16
80 526880 .0135 3/4 3/16