Metric & Imperial Gib Head Keys

The tapered key is tapered only on the side that engages with the hub. [cite: 26] The keyway in the hub has a taper that matches that of the tapered key. [cite: 27] Some taper keys have a gib, or tab, for easier removal during disassembly, hence the name Gib Head Keys [cite: 28]

See our Taper Key Dimensional Charts.

The purpose of the taper is to secure the key itself, as well as, to firmly engage the shaft to the hub without the need for a set screw. [cite: 28] The problem with taper keys is that they can cause the center of the shaft rotation to be slightly off of the mating part. [cite: 29] It is different from a tapered shaft lock in that tapered keys have a matching taper on the keyway, while tapered shaft locks do not. [cite: 30]

The charts below gives the dimensions for Gib Head Keys and Keyways to DIN 6887 and BS46.

Dimensions shown are in Inches and mm, if you wish to convert them please use our universal converter.

GIB HEAD KEYWAYS AND KEYS - DIN 6887

Shaft Diameter		Key Dimensions					Keyway Dimensions					(L) Range
Above	Upto / Inc	Width (W)	Height (H)	Tol (H)	Height (H1)	Chamfer (C)	Width	Depth Shaft (T)	Tol (T)	Depth Hub (T1)	Tol (T1)
10	12	4	4	+0.1	7	0.16	4	2.50	+0.1	1.20	+0.1	14 - 45
12	17	5	5	+0.1	8	0.16	5	3.00	+0.1	1.70	+0.1	14 - 56
17	22	6	6	+0.1	10	0.25	6	3.50	+0.1	2.10	+0.1	16 - 70
22	30	8	7	+0.1	11	0.25	8	4.00	+0.1	2.50	+0.1	20 - 90
30	38	10	8	+0.2	12	0.4	10	5.00	+0.1	2.50	+0.1	25 - 110
38	44	12	8	+0.2	12	0.4	12	5.00	+0.1	2.50	+0.1	32 - 140
44	50	14	9	+0.2	14	0.4	14	5.50	+0.1	2.90	+0.1	40 - 160
50	58	16	10	+0.2	16	0.4	16	6.00	+0.1	3.40	+0.15	45 - 180
58	65	18	11	+0.2	18	0.4	18	7.00	+0.15	3.30	+0.15	50 - 200
65	75	20	12	+0.2	20	0.6	20	7.50	+0.15	3.80	+0.15	56 - 220
75	85	22	14	+0.2	22	0.6	22	8.50	+0.15	4.80	+0.15	63 - 250
85	95	25	14	+0.2	22	0.6	25	9.00	+0.15	4.30	+0.15	70 - 280
95	110	28	16	+0.2	25	0.6	28	10.00	+0.15	5.30	+0.15	80 - 320
110	130	32	18	+0.2	28	0.6	32	11.00	+0.15	6.20	+0.15	90 - 360
130	150	36	20	+0.3	32	1	36	12.00	+0.15	7.20	+0.15	100 - 400
150	170	40	22	+0.3	36	1	40	13.00	+0.15	8.20	+0.15	110 - 400
170	200	45	25	+0.3	40	1	45	15.00	+0.15	9.20	+0.15	125 - 400
200	230	50	28	+0.3	45	1	50	17.00	+0.15	10.10	+0.3	140 - 400
230	260	56	32	+0.3	50	1.6	56	19.00	+0.15	11.10	+0.3	-
260	290	63	32	+0.3	56	1.6	63	20.00	+0.15	12.10	+0.3	-
290	330	70	36	+0.3	63	1.6	70	22.00	+0.15	13.10	+0.3	-
330	380	80	40	+0.3	70	2.5	80	25.00	+0.15	14.10	+0.3	-
380	440	90	45	+0.3	75	2.5	90	28.00	+0.15	16.10	+0.3	-
440	500	100	50	+0.3	80	2.5	100	31.00	+0.15	18.10	+0.3	-

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GIB HEAD KEYWAYS AND KEYS - BS46

Shaft Diameter		Key Dimensions							Keyway Dimensions						(L) Range
Above	Upto / Inc	Width (W)	Tol (W)	Height (H)	Tol (H)	Height (H1)	Height (H2)	Chamfer (C)	Width	Depth Shaft (T)	Tol (T)	Depth Hub (T1)	Tol (T1)	Rad (R)
1/4	1/2	1/8	+0.002	1/8	+0.004	1/4	5/32	0.010	1/8	0.072	+0.006	0.039	+0.006	0.010	-
1/2	3/4	3/16	+0.002	3/16	+0.004	3/8	7/32	0.010	3/16	0.107	+0.006	0.067	+0.006	0.010	1 1/2 to 2
3/4	1	1/4	+0.002	3/16	+0.004	3/8	7/32	0.010	1/4	0.107	+0.006	0.067	+0.006	0.010	1 1/2 to 4
3/4	1	1/4	+0.002	1/4	+0.004	7/16	9/32	0.010	1/4	0.142	+0.006	0.094	+0.006	0.010	1 1/2 to 4
1	1 1/4	5/16	+0.002	1/4	+0.004	7/16	9/32	0.010	5/16	0.142	+0.006	0.094	+0.006	0.010	2 to 4 1/2
1	1 1/4	5/16	+0.002	5/16	+0.004	9/16	11/32	0.010	5/16	0.177	+0.006	0.121	+0.006	0.010	2 to 4 1/2
1 1/4	1 1/2	3/8	+0.002	1/4	+0.004	7/16	9/32	0.010	3/8	0.142	+0.006	0.094	+0.006	0.010	2 to 6
1 1/4	1 1/2	3/8	+0.002	5/16	+0.004	9/16	11/32	0.010	3/8	0.177	+0.006	0.121	+0.006	0.010	2 to 6
1 1/4	1 1/2	3/8	+0.002	3/8	+0.004	5/8	13/32	0.010	3/8	0.213	+0.006	0.148	+0.006	0.010	2 to 6
1 1/2	1 3/4	7/16	+0.002	5/16	+0.004	9/16	11/32	0.020	7/16	0.177	+0.006	0.121	+0.006	0.020	2 1/2 to 6
1 1/2	1 3/4	7/16	+0.002	7/16	+0.004	3/4	15/32	0.020	7/16	0.248	+0.006	0.175	+0.006	0.020	2 1/2 to 6
1 3/4	2	1/2	+0.002	5/16	+0.004	9/16	11/32	0.020	1/2	0.177	+0.006	0.121	+0.006	0.020	2 1/2 to 6 1/2
1 3/4	2	1/2	+0.002	1/2	+0.004	7/8	17/32	0.020	1/2	0.283	+0.006	0.202	+0.006	0.020	2 1/2 to 6 1/2
2	2 1/2	5/8	+0.002	5/8	+0.005	1	21/32	0.020	5/8	0.354	+0.006	0.256	+0.006	0.020	4 1/2 to 8
2 1/2	3	3/4	+0.002	3/4	+0.005	1 1/4	23/32	0.062	3/4	0.424	+0.006	0.310	+0.006	0.062	4 to 8
3	3 1/2	7/8	+0.002	7/8	+0.005	1 3/8	27/32	0.062	7/8	0.495	+0.006	0.370	+0.006	0.062	6 to 8
3 1/2	4	1	+0.003	1	+0.007	1 5/8	1 1/32	0.062	1	0.566	+0.006	0.424	+0.006	0.062	-
4	5	1 1/4	+0.003	1 1/4	+0.007	2	1 9/32	0.062	1 1/4	0.707	+0.006	0.532	+0.006	0.062	-
5	6	1 1/2	+0.004	1 1/2	+0.009	2 1/2	1 17/32	0.062	1 1/2	0.848	+0.006	0.641	+0.006	0.062	-