A machine reamer only has a very slight lead in. Because the reamer and work piece are pre-aligned by the machine there is no risk of it wandering off course. In addition the constant cutting force that can be applied by the machine ensures that it starts cutting immediately. Spiral flutes have the advantage of clearing the swarf automatically but are also available with straight flutes as the amount of swarf generated during a reaming operation should be very small.

MM SIZE

Dia. mm	Cutting Edge Length	OVL	Morse Taper no
3	31	111	1
4	38	118	1
5	44	124	1
6	47	127	1
7	54	134	1
8	58	138	1
9	62	142	1
10	66	146	1
11	71	151	1
12	76	156	1
13	76	156	1
14	81	161	1
15	81	181	2
16	87	187	2
17	87	187	2
18	93	193	2
19	93	193	2
20	100	200	2
21	100	200	2
22	107	207	2
23	107	207	2
24	115	242	3
25	115	242	3
26	115	242	3
27	124	251	3
28	124	251	3
30	124	251	3
32	133	293	4
34	142	302	4
35	142	302	4
36	142	302	4
38	152	312	4
40	152	312	4
42	152	312	4
44	163	323	4
45	163	323	4
46	163	323	4
48	174	334	4
50	174	334	4
52	174	371	5
55	184	381	5
56	184	381	5
58	184	381	5
60	184	381	5
62	194	391	5
63	194	391	5
67	194	391	5
71	203	400	5

INCH SIZE

Dia. Inch	Cutting Edge Length	Overall Length	Morse Taper no
5/32	31	111	1
3/16	38	118	1
7/32	44	124	1
1/4	50	130	1
9/32	54	134	1
5/16	58	138	1
11/32	62	142	1
3/8	66	146	1
7/16	71	151	1
15/32	76	156	1
1/2	76	156	1
9/16	81	181	2
5/8	87	187	2
11/16	93	193	2
3/4	100	200	2
13/16	100	200	2
7/8	107	207	2
15/16	115	242	3
1	115	242	3
1  1/16	124	251	3
1  1/8	124	251	3
1 3/16,1 1/4	133	260	3
1  5/16	133	293	4
1  3/8	142	302	4
1  7/16	142	302	4
1  1/2	152	312	4
1  5/8	152	312	4
1  3/4	163	323	4
1  7/8	174	334	4
2	174	334	4
2  1/4	184	381	5
2  1/2	194	391	5
3	212	409	5