What is a Type H headed press fit bushing?

A Type H bushing is pressed directly into the jig plate and retained by a head. It guides tools such as drills and reamers and is commonly used when space is limited or production runs are shorter.

When should I choose Type H instead of a liner or renewable bushing?

Choose Type H when hole spacing is too close for liners, when replacement is unlikely, or when you want a compact, cost-effective guide per ASME B94.33 without a liner.

How should the jig bore be prepared for a press fit?

Ream the hole to the finished body diameter tolerance shown in the table. Press in with an arbor press to prevent distortion and ensure concentricity.

AMESWEB

Headed Press Fit Bushing Dimensions (Type H)

ASME B94.33 (Inch Series)

Diagram of Type H headed press fit jig bushing with labeled dimensions — Head-type press fit jig bushing (Type H) dimensional callouts.

What is a Headed Press Fit Bushing?

A headed press fit bushing (ASME Type H) is a precision guide pressed directly into the jig plate, with a head to prevent movement. It’s preferred where liner bushings won’t fit or where renewable inserts are unnecessary. Dimensions below follow ASME B94.33 and are given in inches.

The maximum and minimum values of hole size A are given in Type-P Plain press fit bushing dimensions.

Type H headed press fit bushing dimensions per ASME B94.33 (inch).
Range of Hole Diameters A	Body Diameter B			Body Length ±1/64 C	Radius Min. D	Head Diameter ±1/64 E	Head Thickness ±1/64 F	Number
	Nominal	Finished
	Nominal	Max.	Min.
#80 to 1/16	5/32	0.1578	0.1575	1/4	1/64	1/4	3/32	H-10-4
#80 to 1/16	5/32	0.1578	0.1575	5/16	1/64	1/4	3/32	H-10-5
#80 to 1/16	5/32	0.1578	0.1575	3/8	1/64	1/4	3/32	H-10-6
#80 to 1/16	5/32	0.1578	0.1575	1/2	1/64	1/4	3/32	H-10-8
1/16 to #39	13/64	0.2046	0.2043	1/4	1/64	19/64	3/32	H-13-4
1/16 to #39	13/64	0.2046	0.2043	5/16	1/64	19/64	3/32	H-13-5
1/16 to #39	13/64	0.2046	0.2043	3/8	1/64	19/64	3/32	H-13-6
1/16 to #39	13/64	0.2046	0.2043	1/2	1/64	19/64	3/32	H-13-8
#40 to 9/64	1/4	0.2516	0.2513	1/4	1/64	23/64	3/32	H-16-4
#40 to 9/64	1/4	0.2516	0.2513	5/16	1/64	23/64	3/32	H-16-5
#40 to 9/64	1/4	0.2516	0.2513	3/8	1/64	23/64	3/32	H-16-6
#40 to 9/64	1/4	0.2516	0.2513	1/2	1/64	23/64	3/32	H-16-8
#40 to 9/64	1/4	0.2516	0.2513	3/4	1/64	23/64	3/32	H-16-12
1/8 to #10	5/16	0.3141	0.3138	1/4	1/32	27/64	1/8	H-20-4
1/8 to #10	5/16	0.3141	0.3138	5/16	1/32	27/64	1/8	H-20-5
1/8 to #10	5/16	0.3141	0.3138	3/8	1/32	27/64	1/8	H-20-6
1/8 to #10	5/16	0.3141	0.3138	1/2	1/32	27/64	1/8	H-20-8
1/8 to #10	5/16	0.3141	0.3138	3/4	1/32	27/64	1/8	H-20-12
#11 to 5/32	11/32	0.3453	0.3450	1/4	1/32	29/64	1/8	H-23-4
#11 to 5/32	11/32	0.3453	0.3450	5/16	1/32	29/64	1/8	H-23-5
#11 to 5/32	11/32	0.3453	0.3450	3/8	1/32	29/64	1/8	H-23-6
#11 to 5/32	11/32	0.3453	0.3450	1/2	1/32	29/64	1/8	H-23-8
#11 to 5/32	11/32	0.3453	0.3450	3/4	1/32	29/64	1/8	H-23-12
11/64 to 3/16	3/8	0.3766	0.3763	1/4	1/32	31/64	1/8	H-25-4
11/64 to 3/16	3/8	0.3766	0.3763	5/16	1/32	31/64	1/8	H-25-5
11/64 to 3/16	3/8	0.3766	0.3763	3/8	1/32	31/64	1/8	H-25-6
11/64 to 3/16	3/8	0.3766	0.3763	1/2	1/32	31/64	1/8	H-25-8
11/64 to 3/16	3/8	0.3766	0.3763	3/4	1/32	31/64	1/8	H-25-12
13/64 to 7/32	7/16	0.4391	0.4388	5/16	1/32	35/64	1/8	H-28-5
13/64 to 7/32	7/16	0.4391	0.4388	3/8	1/32	35/64	1/8	H-28-6
13/64 to 7/32	7/16	0.4391	0.4388	1/2	1/32	35/64	1/8	H-28-8
13/64 to 7/32	7/16	0.4391	0.4388	3/4	1/32	35/64	1/8	H-28-12
15/64 to 1/4	15/32	0.4703	0.4700	5/16	1/32	37/64	5/32	H-31-5
15/64 to 1/4	15/32	0.4703	0.4700	3/8	1/32	37/64	5/32	H-31-6
15/64 to 1/4	15/32	0.4703	0.4700	1/2	1/32	37/64	5/32	H-31-8
15/64 to 1/4	15/32	0.4703	0.4700	3/4	1/32	37/64	5/32	H-31-12
17/64 to 9/32	17/32	0.5330	0.5326	5/16	1/32	41/64	5/32	H-34-5
17/64 to 9/32	17/32	0.5330	0.5326	3/8	1/32	41/64	5/32	H-34-6
17/64 to 9/32	17/32	0.5330	0.5326	1/2	1/32	41/64	5/32	H-34-8
17/64 to 9/32	17/32	0.5330	0.5326	3/4	1/32	41/64	5/32	H-34-12
19/64 to 5/16	9/16	0.5642	0.5638	5/16	1/32	43/64	3/16	H-37-5
19/64 to 5/16	9/16	0.5642	0.5638	3/8	1/32	43/64	3/16	H-37-6
19/64 to 5/16	9/16	0.5642	0.5638	1/2	1/32	43/64	3/16	H-37-8
19/64 to 5/16	9/16	0.5642	0.5638	3/4	1/32	43/64	3/16	H-37-12
21/64 to 11/32	5/8	0.6269	0.6265	3/8	1/32	47/64	3/16	H-40-6
21/64 to 11/32	5/8	0.6269	0.6265	1/2	1/32	47/64	3/16	H-40-8
21/64 to 11/32	5/8	0.6269	0.6265	3/4	1/32	47/64	3/16	H-40-12
23/64 to 3/8	21/32	0.6581	0.6577	3/8	1/32	49/64	3/16	H-43-6
23/64 to 3/8	21/32	0.6581	0.6577	1/2	1/32	49/64	3/16	H-43-8
23/64 to 3/8	21/32	0.6581	0.6577	3/4	1/32	49/64	3/16	H-43-12
25/64 to 13/32	11/16	0.7208	0.7204	3/8	1/16	53/64	7/32	H-46-6
25/64 to 13/32	11/16	0.7208	0.7204	1/2	1/16	53/64	7/32	H-46-8
25/64 to 13/32	11/16	0.7208	0.7204	3/4	1/16	53/64	7/32	H-46-12
27/64 to 7/16	3/4	0.7520	0.7516	3/8	1/16	55/64	7/32	H-49-6
27/64 to 7/16	3/4	0.7520	0.7516	1/2	1/16	55/64	7/32	H-49-8
27/64 to 7/16	3/4	0.7520	0.7516	3/4	1/16	55/64	7/32	H-49-12
29/64 to 15/32	7/8	0.8770	0.8765	1/2	1/16	63/64	1/4	H-56-8
29/64 to 15/32	7/8	0.8770	0.8765	3/4	1/16	63/64	1/4	H-56-12
31/64 to 1/2	15/16	0.9395	0.9390	1/2	1/16	1 1/64	1/4	H-62-8
31/64 to 1/2	15/16	0.9395	0.9390	3/4	1/16	1 1/64	1/4	H-62-12
33/64 to 17/32	1	1.0020	1.0015	1/2	1/16	1 5/64	5/16	H-68-8
33/64 to 17/32	1	1.0020	1.0015	3/4	1/16	1 5/64	5/16	H-68-12
35/64 to 9/16	1 1/16	1.0645	1.0640	1/2	1/16	1 9/64	5/16	H-75-8
35/64 to 9/16	1 1/16	1.0645	1.0640	3/4	1/16	1 9/64	5/16	H-75-12
37/64 to 19/32	1 1/8	1.1270	1.1266	1/2	1/16	1 13/64	5/16	H-81-8
37/64 to 19/32	1 1/8	1.1270	1.1266	3/4	1/16	1 13/64	5/16	H-81-12
39/64 to 5/8	1 3/16	1.1895	1.1891	1/2	1/16	1 17/64	5/16	H-87-8
39/64 to 5/8	1 3/16	1.1895	1.1891	3/4	1/16	1 17/64	5/16	H-87-12
41/64 to 21/32	1 1/4	1.2520	1.2516	3/4	1/16	1 21/64	3/8	H-93-12
43/64 to 11/16	1 5/16	1.3145	1.3141	3/4	1/16	1 25/64	3/8	H-100-12
45/64 to 23/32	1 3/8	1.3770	1.3766	3/4	1/16	1 29/64	3/8	H-106-12
47/64 to 3/4	1 7/16	1.4395	1.4391	3/4	1/16	1 33/64	3/8	H-112-12
47/64 to 3/4	1 7/16	1.4395	1.4391	1	1/16	1 33/64	3/8	H-112-16
3/4 to 1	1 3/4	1.7523	1.7519	1	3/32	1 63/64	3/8	H-112-16
1 to 1 3/8	1 3/4	1.7523	1.7519	1 1/4	3/32	1 63/64	3/8	H-112-20
1 to 1 3/8	1 3/4	1.7523	1.7519	1 1/2	3/32	1 63/64	3/8	H-112-24
1 to 1 3/8	1 3/4	1.7523	1.7519	1 3/4	3/32	1 63/64	3/8	H-112-28
1 to 1 3/8	1 3/4	1.7523	1.7519	2 1/8	3/32	1 63/64	3/8	H-112-32
3/4 to 1	2	2.0026	2.0022	1	3/32	2 7/32	3/8	H-125-16
1 to 1 3/8	2	2.0026	2.0022	1 1/4	3/32	2 7/32	3/8	H-125-20
1 to 1 3/8	2	2.0026	2.0022	1 1/2	3/32	2 7/32	3/8	H-125-24
1 to 1 3/8	2	2.0026	2.0022	1 3/4	3/32	2 7/32	3/8	H-125-28
1 to 1 3/8	2	2.0026	2.0022	2 1/8	3/32	2 7/32	3/8	H-125-32
1 3/8 to 1 3/4	2	2.0026	2.0022	2 1/2	3/32	2 7/32	3/8	H-125-40
3/4 to 1	2 1/8	2.1276	2.1272	1	3/32	2 19/64	3/8	H-131-16
1 to 1 3/8	2 1/8	2.1276	2.1272	1 1/4	3/32	2 19/64	3/8	H-131-20
1 to 1 3/8	2 1/8	2.1276	2.1272	1 1/2	3/32	2 19/64	3/8	H-131-24
1 to 1 3/8	2 1/8	2.1276	2.1272	1 3/4	3/32	2 19/64	3/8	H-131-28
1 to 1 3/8	2 1/8	2.1276	2.1272	2 1/8	3/32	2 19/64	3/8	H-131-32
1 3/8 to 1 3/4	2 1/8	2.1276	2.1272	2 1/2	3/32	2 19/64	3/8	H-131-40
3/4 to 1	2 1/4	2.2525	2.2521	1	3/32	2 31/64	3/8	H-137-16
1 to 1 3/8	2 1/4	2.2525	2.2521	1 1/4	3/32	2 31/64	3/8	H-137-20
1 to 1 3/8	2 1/4	2.2525	2.2521	1 1/2	3/32	2 31/64	3/8	H-137-24
1 to 1 3/8	2 1/4	2.2525	2.2521	1 3/4	3/32	2 31/64	3/8	H-137-28
1 to 1 3/8	2 1/4	2.2525	2.2521	2 1/8	3/32	2 31/64	3/8	H-137-32
1 3/8 to 1 3/4	2 1/4	2.2525	2.2521	2 1/2	3/32	2 31/64	3/8	H-137-40
3/4 to 1	2 1/4	2.2525	2.2521	1	3/32	2 31/64	3/8	H-144-16
1 to 1 3/8	2 1/4	2.2525	2.2521	1 1/4	3/32	2 31/64	3/8	H-144-20
1 to 1 3/8	2 1/4	2.2525	2.2521	1 1/2	3/32	2 31/64	3/8	H-144-24
1 to 1 3/8	2 1/4	2.2525	2.2521	1 3/4	3/32	2 31/64	3/8	H-144-28
1 to 1 3/8	2 1/4	2.2525	2.2521	2 1/8	3/32	2 31/64	3/8	H-144-32
1 3/8 to 1 3/4	2 1/4	2.2525	2.2521	2 1/2	3/32	2 31/64	3/8	H-144-40
1 3/8 to 1 3/4	2 1/4	2.2525	2.2521	3	3/32	2 31/64	3/8	H-144-48

Applications and Benefits

Precision drilling/reaming: Maintains accurate hole size and position.
Compact & cost-effective: No liner required; ideal for short to medium runs.
Tight spacing: Suitable when hole centers are too close for liner bushings.
Standardized: Interchangeable per ASME B94.33.

Engineering Notes

Match the jig bore to the finished body diameter tolerance shown in the table to achieve a reliable press fit. Ream the bore and press the bushing using an arbor press (avoid hammering) to maintain concentricity and reduce wear. Consider head diameter E and thickness F for adequate seating and plate thickness.

Explore Other Bushing Types

See dimensional charts for Type P plain press fit bushings, Type HL head liner bushings, and Type SF slip-fixed renewable bushings.

Reference

ASME B94.33-1996, Jig Bushings (Inch Series)