Internal Helical Slot Laps, Arbors, And Expanders

Expanding Internal Laps

should be longer than the length of the bore being lapped.

Standard Internal Laps

are manufactured undersize to allow for stock removal and abrasive clearance. Order a 1/4″ lap to finish a .2500 dia. bore.

Radial Grooves

are recommended for most lapping applications; however, there are instances when non-grooved laps are recommended, such as when lapping interrupted bores.

*Standard lap arbors 4/0 thru 5 are manufactured without centers. These arbors are available with centers (additional charge)

Part # With Radial Grooves	Part # No Radial Grooves	A Lap Size	B Length	Arbor	A Shank Diameter	B Shank Length	C Taper Length	Expander	Lap Puller
N/A	3/64 NSIL	3/64	1/2	4/0 SLA*	1/8	3/4	1-1/2	4/0 SLE	0LP
N/A	1/16 SIL	1/16	5/8	3/0 SLA*	1/8	3/4	1-1/2	3/0 SLE	0LP
N/A	5/64 SIL	5/64	5/8	3/0 SLA*	1/8	3/4	1-1/2	3/0 SLE	0LP
N/A	3/32 SIL	3/32	3/4	2/0 SLA*	1/8	3/4	1-5/8	2/0 SLE	0LP
N/A	7/64 SIL	7/64	3/4	2/0 SLA*	1/8	3/4	1-5/8	2/0 SLE	0LP
N/A	1/8 SIL	1/8	7/8	0 SLA*	1/8	3/4	1-3/4	0 SLE	0LP
N/A	5/32 SIL	5/32	7/8	0 SLA*	1/8	3/4	1-3/4	0 SLE	0LP
N/A	9/64 SIL	9/64	7/8	0 SLA*	1/8	3/4	1-3/4	0 SLE	0LP
N/A	11/64 SIL	11/64	7/8	0 SLA*	1/8	3/4	1-3/4	0 SLE	0LP
3/16 SILS	3/16 SILSNRG	3/16	1	1 SLA*	3/16	1	2-3/4	1 SLE	1LP
3/16 SILL	3/16 SILLNRG	3/16	1-3/8	1 SLA*	3/16	1	2-3/4	1 SLE	1LP
13/64 SILS	13/64 SILSNRG	13/64	1	1 SLA*	3/16	1	2-3/4	1 SLE	1LP
13/64 SILL	13/64 SILLNRG	13/64	1-3/8	1 SLA*	3/16	1	2-3/4	1 SLE	1LP
7/32 SILS	7/32 SILSNRG	7/32	1-1/4	2 SLA*	3/16	1	3	2 SLE	1LP
7/32 SILL	7/32 SILLNRG	7/32	1-3/4	2 SLA*	3/16	1	3	2 SLE	1LP
15/64 SILS	15/64 SILSNRG	15/64	1-1/4	2 SLA*	3/16	1	3	2 SLE	1LP
15/64 SILL	15/64 SILLNRG	15/64	1-3/4	2 SLA*	3/16	1	3	2 SLE	1LP
1/4 SILS	1/4 SILSNRG	1/4	1-1/2	3 SLA*	3/16	1	4	3 SLE	1LP
1/4 SILL	1/4 SILLNRG	1/4	2	3 SLA*	3/16	1	4	3 SLE	1LP
17/64 SILS	17/64 SILSNRG	17/64	1-1/2	3 SLA*	3/16	1	4	3 SLE	1LP
17/64 SILL	17/64 SILLNRG	17/64	2	3 SLA*	3/16	1	4	3 SLE	1LP
9/32 SILS	9/32 SILSNRG	9/32	1-1/2	3 SLA*	3/16	1	4	3 SLE	1LP
9/32 SILL	9/32 SILLNRG	9/32	2	3 SLA*	3/16	1	4	3 SLE	1LP
19/64 SILS	19/64 SILSNRG	19/64	1-1/2	3 SLA*	3/16	1	4	3 SLE	1LP
19/64 SILL	19/64 SILLNRG	19/64	2	3 SLA*	3/16	1	4	3 SLE	1LP
5/16 SILS	5/16 SILSNRG	5/16	1-1/2	4 SLA*	7/32	1	4	4 SLE	1LP
5/16 SILL	5/16 SILLNRG	5/16	2	4 SLA*	7/32	1	4	4 SLE	1LP
21/64 SILS	21/64 SILSNRG	21/64	1-1/2	4 SLA*	7/32	1	4	4 SLE	1LP
21/64 SILL	21/64 SILLNRG	21/64	2	4 SLA*	7/32	1	4	4 SLE	1LP
11/32 SILS	11/32 SILSNRG	11/32	1-1/2	4 SLA*	7/32	1	4	4 SLE	1LP
11/32 SILL	11/32 SILLNRG	11/32	2	4 SLA*	7/32	1	4	4 SLE	1LP
23/64 SILS	23/64 SILSNRG	23/64	1-1/2	4 SLA*	7/32	1	4	4 SLE	1LP
23/64 SILL	23/64 SILLNRG	23/64	2	4 SLA*	7/32	1	4	4 SLE	1LP
3/8 SILS	3/8 SILSNRG	3/8	1-3/4	5 SLA*	9/32	1-1/2	5	5 SLE	1LP
3/8 SILL	3/8 SILLNRG	3/8	2-1/2	5 SLA*	9/32	1-1/2	5	5 SLE	1LP
25/64 SILS	25/64 SILSNRG	25/64	1-3/4	5 SLA*	9/32	1-1/2	5	5 SLE	1LP
25/64 SILL	25/64 SILLNRG	25/64	2-1/2	5 SLA*	9/32	1-1/2	5	5 SLE	1LP
13/32 SILS	13/32 SILSNRG	13/32	1-3/4	5 SLA*	9/32	1-1/2	5	5 SLE	1LP
13/32 SILL	13/32 SILLNRG	13/32	2-1/2	5 SLA*	9/32	1-1/2	5	5 SLE	1LP
27/64 SILS	27/64 SILSNRG	27/64	1-3/4	5 SLA*	9/32	1-1/2	5	5 SLE	1LP
27/64 SILL	27/64 SILLNRG	27/64	2-1/2	5 SLA*	9/32	1-1/2	5	5 SLE	1LP
7/16 SILS	7/16 SILSNRG	7/16	1-3/4	6 SLA	5/16	1-1/2	5	6 SLE	1LP
7/16 SILL	7/16 SILLNRG	7/16	2-1/2	6 SLA	5/16	1-1/2	5	6 SLE	1LP
29/64 SILS	29/64 SILSNRG	29/64	1-3/4	6 SLA	5/16	1-1/2	5	6 SLE	1LP
29/64 SILL	29/64 SILLNRG	29/64	2-1/2	6 SLA	5/16	1-1/2	5	6 SLE	1LP
15/32 SILS	15/32 SILSNRG	15/32	1-3/4	6 SLA	5/16	1-1/2	5	6 SLE	1LP
15/32 SILL	15/32 SILLNRG	15/32	2-1/2	6 SLA	5/16	1-1/2	5	6 SLE	1LP
31/64 SILS	31/64 SILSNRG	31/64	1-3/4	6 SLA	5/16	1-1/2	5	6 SLE	1LP
31/64 SILL	31/64 SILLNRG	31/64	2-1/2	6 SLA	5/16	1-1/2	5	6 SLE	1LP
1/2 SILS	1/2 SILSNRG	1/2	2-1/4	7 SLA	3/8	1-1/2	6	7 SLE	1LP
1/2 SILL	1/2 SILLNRG	1/2	3-1/4	7 SLA	3/8	1-1/2	6	7 SLE	1LP
33/64 NSILS	33/64 NSILSNRG	33/64	2-1/4	7 SLA	3/8	1-1/2	6	7 SLE	1LP
33/64 NSILL	33/64 NSILLNRG	33/64	3-1/4	7 SLA	3/8	1-1/2	6	7 SLE	1LP
17/32 SILS	17/32 SILSNRG	17/32	2-1/4	7 SLA	3/8	1-1/2	6	7 SLE	1LP
17/32 SILL	17/32 SILLNRG	17/32	3-1/4	7 SLA	3/8	1-1/2	6	7 SLE	1LP
35/64 NSILS	35/64 NSILSNRG	35/64	2-1/4	7 SLA	3/8	1-1/2	6	7 SLE	1LP
35/64 NSILL	35/64 NSILLNRG	35/64	3-1/4	7 SLA	3/8	1-1/2	6	7 SLE	1LP
9/16 SILS	9/16 SILSNRG	9/16	2-1/4	7 SLA	3/8	1-1/2	6	7 SLE	1LP
9/16 SILL	9/16 SILLNRG	9/16	3-1/4	7 SLA	3/8	1-1/2	6	7 SLE	1LP
37/64 NSILS	37/64 NSILSNRG	37/64	2-1/4	7 SLA	3/8	1-1/2	6	7 SLE	1LP
37/64 NSILL	37/64 NSILLNRG	37/64	3-1/4	7 SLA	3/8	1-1/2	6	7 SLE	1LP
19/32 SILS	19/32 SILSNRG	19/32	2-1/4	7 SLA	3/8	1-1/2	6	7 SLE	1LP
19/32 SILL	19/32 SILLNRG	19/32	3-1/4	7 SLA	3/8	1-1/2	6	7 SLE	1LP
39/64 NSILS	39/64 NSILSNRG	39/64	2-1/4	7 SLA	3/8	1-1/2	6	7 SLE	1LP
39/64 NSILL	39/64 NSILLNRG	39/64	3-1/4	7 SLA	3/8	1-1/2	6	7 SLE	1LP
5/8 SILS	5/8 SILSNRG	5/8	2-1/4	8 SLA	13/32	1-1/2	6	8 SLE	2LP
5/8 SILL	5/8 SILLNRG	5/8	3-1/4	8 SLA	13/32	1-1/2	6	8 SLE	2LP
41/64 NSILS	41/64 NSILSNRG	41/64	2-1/4	8 SLA	13/32	1-1/2	6	8 SLE	2LP
41/64 NSILL	41/64 NSILLNRG	41/64	3-1/4	8 SLA	13/32	1-1/2	6	8 SLE	2LP
21/32 SILS	21/32 SILSNRG	21/32	2-1/4	8 SLA	13/32	1-1/2	6	8 SLE	2LP
21/32 SILL	21/32 SILLNRG	21/32	3-1/4	8 SLA	13/32	1-1/2	6	8 SLE	2LP
43/64 NSILS	43/64 NSILSNRG	43/64	2-1/4	8 SLA	13/32	1-1/2	6	8 SLE	2LP
43/64 NSILL	43/64 NSILLNRG	43/64	3-1/4	8 SLA	13/32	1-1/2	6	8 SLE	2LP
11/16 SILS	11/16 SILSNRG	11/16	2-1/4	8 SLA	13/32	1-1/2	6	8 SLE	2LP
11/16 SILL	11/16 SILLNRG	11/16	3-1/4	8 SLA	13/32	1-1/2	6	8 SLE	2LP
45/64 NSILS	45/64 NSILSNRG	45/64	2-1/4	8 SLA	13/32	1-1/2	6	8 SLE	2LP
45/64 NSILL	45/64 NSILLNRG	45/64	3-1/4	8 SLA	13/32	1-1/2	6	8 SLE	2LP
23/32 SILS	23/32 SILSNRG	23/32	2-1/4	8 SLA	13/32	1-1/2	6	8 SLE	2LP
23/32 SILL	23/32 SILLNRG	23/32	3-1/4	8 SLA	13/32	1-1/2	6	8 SLE	2LP
47/64 NSILS	47/64 NSILSNRG	47/64	2-1/4	8 SLA	13/32	1-1/2	6	8 SLE	2LP
47/64 NSILL	47/64 NSILLNRG	47/64	3-1/4	8 SLA	13/32	1-1/2	6	8 SLE	2LP
3/4 SILS	3/4 SILSNRG	3/4	2-1/2	9 SLA	1/2	2	7	9 SLE	2LP
3/4 SILL	3/4 SILLNRG	3/4	3-1/2	9 SLA	1/2	2	7	9 SLE	2LP
49/64 NSILS	49/64 NSILSNRG	49/64	2-1/2	9 SLA	1/2	2	7	9 SLE	2LP
49/64 NSILL	49/64 NSILLNRG	49/64	3-1/2	9 SLA	1/2	2	7	9 SLE	2LP
25/32 SILS	25/32 SILSNRG	25/32	2-1/2	9 SLA	1/2	2	7	9 SLE	2LP
25/32 SILL	25/32 SILLNRG	25/32	3-1/2	9 SLA	1/2	2	7	9 SLE	2LP
51/64 NSILS	51/64 NSILSNRG	51/64	2-1/2	9 SLA	1/2	2	7	9 SLE	2LP
51/64 NSILL	51/64 NSILLNRG	51/64	3-1/2	9 SLA	1/2	2	7	9 SLE	2LP
13/16 SILS	13/16 SILSNRG	13/16	2-1/2	9 SLA	1/2	2	7	9 SLE	2LP
13/16 SILL	13/16 SILLNRG	13/16	3-1/2	9 SLA	1/2	2	7	9 SLE	2LP
53/64 NSILS	53/64 NSILSNRG	53/64	2-1/2	9 SLA	1/2	2	7	9 SLE	2LP
53/64 NSILL	53/64 NSILLNRG	53/64	3-1/2	9 SLA	1/2	2	7	9 SLE	2LP
27/32 SILS	27/32 SILSNRG	27/32	2-1/2	9 SLA	1/2	2	7	9 SLE	2LP
27/32 SILL	27/32 SILLNRG	27/32	3-1/2	9 SLA	1/2	2	7	9 SLE	2LP
55/64 NSILS	55/64 NSILSNRG	55/64	2-1/2	9 SLA	1/2	2	7	9 SLE	2LP
55/64 NSILL	55/64 NSILLNRG	55/64	3-1/2	9 SLA	1/2	2	7	9 SLE	2LP
7/8 SILS	7/8 SILSNRG	7/8	2-1/2	10 SLA	9/16	2	7	10 SLE	2LP
7/8 SILL	7/8 SILLNRG	7/8	3-1/2	10 SLA	9/16	2	7	10 SLE	2LP
57/64 NSILS	57/64 NSILSNRG	57/64	2-1/2	10 SLA	9/16	2	7	10 SLE	2LP
57/64 NSILL	57/64 NSILLNRG	57/64	3-1/2	10 SLA	9/16	2	7	10 SLE	2LP
29/32 SILS	29/32 SILSNRG	29/32	2-1/2	10 SLA	9/16	2	7	10 SLE	2LP
29/32 SILL	29/32 SILLNRG	29/32	3-1/2	10 SLA	9/16	2	7	10 SLE	2LP
59/64 NSILS	59/64 NSILSNRG	59/64	2-1/2	10 SLA	9/16	2	7	10 SLE	2LP
59/64 NSILL	59/64 NSILLNRG	59/64	3-1/2	10 SLA	9/16	2	7	10 SLE	2LP
15/16 SILS	15/16 SILSNRG	15/16	2-1/2	10 SLA	9/16	2	7	10 SLE	2LP
15/16 SILL	15/16 SILLNRG	15/16	3-1/2	10 SLA	9/16	2	7	10 SLE	2LP
61/64 NSILS	61/64 NSILSNRG	61/64	2-1/2	10 SLA	9/16	2	7	10 SLE	2LP
61/64 NSILL	61/64 NSILLNRG	61/64	3-1/2	10 SLA	9/16	2	7	10 SLE	2LP
31/32 SILS	31/32 SILSNRG	31/32	2-1/2	10 SLA	9/16	2	7	10 SLE	2LP
31/32 SILL	31/32 SILLNRG	31/32	3-1/2	10 SLA	9/16	2	7	10 SLE	2LP
63/64 NSILS	63/64 NSILSNRG	63/64	2-1/2	10 SLA	9/16	2	7	10 SLE	2LP
63/64 NSILL	63/64 NSILLNRG	63/64	3-1/2	10 SLA	9/16	2	7	10 SLE	2LP
1 SILS	1 SILSNRG	1	3	11 SLA	3/4	2	8	11 SLE	2LP
1 SILL	1 SILLNRG	1	4	11 SLA	3/4	2	8	11 SLE	2LP
1-1/64 NSILS	1-1/64 NSILSNRG	1-1/64	3	11 SLA	3/4	2	8	11 SLE	2LP
1-1/64 NSILL	1-1/64 NSILLNRG	1-1/64	4	11 SLA	3/4	2	8	11 SLE	2LP
1-1/32 NSILS	1-1/32 NSILSNRG	1-1/32	3	11 SLA	3/4	2	8	11 SLE	2LP
1-1/32 NSILL	1-1/32 NSILLNRG	1-1/32	4	11 SLA	3/4	2	8	11 SLE	2LP
1-3/64 NSILS	1-3/64 NSILSNRG	1-3/64	3	11 SLA	3/4	2	8	11 SLE	2LP
1-3/64 NSILL	1-3/64 NSILLNRG	1-3/64	4	11 SLA	3/4	2	8	11 SLE	2LP
1-1/16 SILS	1-1/16 SILSNRG	1-1/16	3	11 SLA	3/4	2	8	11 SLE	2LP
1-1/16 SILL	1-1/16 SILLNRG	1-1/16	4	11 SLA	3/4	2	8	11 SLE	2LP
1-5/64 NSILS	1-5/64 NSILSNRG	1-5/64	3	11 SLA	3/4	2	8	11 SLE	2LP
1-5/64 NSILL	1-5/64 NSILLNRG	1-5/64	4	11 SLA	3/4	2	8	11 SLE	2LP
1-3/32 NSILS	1-3/32 NSILSNRG	1-3/32	3	11 SLA	3/4	2	8	11 SLE	2LP
1-3/32 NSILL	1-3/32 NSILLNRG	1-3/32	4	11 SLA	3/4	2	8	11 SLE	2LP
1-7/64 NSILS	1-7/64 NSILSNRG	1-7/64	3	11 SLA	3/4	2	8	11 SLE	2LP
1-7/64 NSILL	1-7/64 NSILLNRG	1-7/64	4	11 SLA	3/4	2	8	11 SLE	2LP
1-1/8 SILS	1-1/8 SILSNRG	1-1/8	3	11 SLA	3/4	2	8	11 SLE	2LP
1-1/8 SILL	1-1/8 SILLNRG	1-1/8	4	11 SLA	3/4	2	8	11 SLE	2LP
1-9/64 NSILS	1-9/64 NSILSNRG	1-9/64	3	11 SLA	3/4	2	8	11 SLE	2LP
1-9/64 NSILL	1-9/64 NSILLNRG	1-9/64	4	11 SLA	3/4	2	8	11 SLE	2LP
1-5/32 NSILS	1-5/32 NSILSNRG	1-5/32	3	11 SLA	3/4	2	8	11 SLE	2LP
1-5/32 NSILL	1-5/32 NSILLNRG	1-5/32	4	11 SLA	3/4	2	8	11 SLE	2LP
1-11/64 NSILS	1-11/64 NSILSNRG	1-11/64	3	11 SLA	3/4	2	8	11 SLE	2LP
1-11/64 NSILL	1-11/64 NSILLNRG	1-11/64	4	11 SLA	3/4	2	8	11 SLE	2LP
1-3/16 SILS	1-3/16 SILSNRG	1-3/16	3	11 SLA	3/4	2	8	11 SLE	2LP
1-3/16 SILL	1-3/16 SILLNRG	1-3/16	4	11 SLA	3/4	2	8	11 SLE	2LP
1-13/64 NSILS	1-13/64 NSILSNRG	1-13/64	3	11 SLA	3/4	2	8	11 SLE	2LP
1-13/64 NSILL	1-13/64 NSILLNRG	1-13/64	4	11 SLA	3/4	2	8	11 SLE	2LP
1-7/32 NSILS	1-7/32 NSILSNRG	1-7/32	3	11 SLA	3/4	2	8	11 SLE	2LP
1-7/32 NSILL	1-7/32 NSILLNRG	1-7/32	4	11 SLA	3/4	2	8	11 SLE	2LP
1-15/64 NSILS	1-15/64 NSILSNRG	1-15/64	3	11 SLA	3/4	2	8	11 SLE	2LP
1-15/64 NSILL	1-15/64 NSILLNRG	1-15/64	4	11 SLA	3/4	2	8	11 SLE	2LP
1-1/4 SILS	1-1/4 SILSNRG	1-1/4	3	11 SLA	3/4	2	8	11 SLE	2LP
1-1/4 SILL	1-1/4 SILLNRG	1-1/4	4	11 SLA	3/4	2	8	11 SLE	2LP
1-5/16 SIL	1-5/16 SILNRG	1-5/16	4	12 SLA	7/8	2-1/2	7-1/2	12 SLE	3LP
1-3/8 SIL	1-3/8 SILNRG	1-3/8	4	12 SLA	7/8	2-1/2	7-1/2	12 SLE	3LP
1-7/16 SIL	1-7/16 SILNRG	1-7/16	4	12 SLA	7/8	2-1/2	7-1/2	12 SLE	3LP
1-1/2 SIL	1-1/2 SILNRG	1-1/2	4	12 SLA	7/8	2-1/2	7-1/2	12 SLE	3LP
1-9/16 SIL	1-9/16 SILNRG	1-9/16	4	12 SLA	7/8	2-1/2	7-1/2	12 SLE	3LP
1-5/8 SIL	1-5/8 SILNRG	1-5/8	4	12 SLA	7/8	2-1/2	7-1/2	12 SLE	3LP
1-11/16 SIL	1-11/16 SILNRG	1-11/16	4	13 SLA	1	2-1/2	7-1/2	13 SLE	3LP
1-3/4 SIL	1-3/4 SILNRG	1-3/4	4	13 SLA	1	2-1/2	7-1/2	13 SLE	3LP
1-13/16 SIL	1-13/16 SILNRG	1-13/16	4	13 SLA	1	2-1/2	7-1/2	13 SLE	3LP
1-7/8 SIL	1-7/8 SILNRG	1-7/8	4	13 SLA	1	2-1/2	7-1/2	13 SLE	3LP
1-15/16 SIL	1-15/16 SILNRG	1-15/16	4	13 SLA	1	2-1/2	7-1/2	13 SLE	3LP
2 SIL	2 SILNRG	2	4	13 SLA	1	2-1/2	7-1/2	13 SLE	3LP
2-1/16 NSIL	2-1/16 NSILNRG	2-1/16	4	14 SLA	1-1/4	2-1/2	7-1/2	14 SLE	3LP
2-1/8 NSIL	2-1/8 NSILNRG	2-1/8	4	14 SLA	1-1/4	2-1/2	7-1/2	14 SLE	3LP
2-3/16 NSIL	2-3/16 NSILNRG	2-3/16	4	14 SLA	1-1/4	2-1/2	7-1/2	14 SLE	3LP
2-1/4 NSIL	2-1/4 NSILNRG	2-1/4	4	14 SLA	1-1/4	2-1/2	7-1/2	14 SLE	3LP
2-5/16 NSIL	2-5/16 NSILNRG	2-5/16	4	14 SLA	1-1/4	2-1/2	7-1/2	14 SLE	3LP
2-3/8 NSIL	2-3/8 NSILNRG	2-3/8	4	14 SLA	1-1/4	2-1/2	7-1/2	14 SLE	3LP
2-7/16 NSIL	2-7/16 NSILNRG	2-7/16	4	15 SLA	1-1/2	2-1/2	7-1/2	15 SLE	3LP
2-1/2 NSIL	2-1/2 NSILNRG	2-1/2	4	15 SLA	1-1/2	2-1/2	7-1/2	15 SLE	3LP
2-9/16 NSIL	2-9/16 NSILNRG	2-9/16	4	15 SLA	1-1/2	2-1/2	7-1/2	15 SLE	3LP
2-5/8 NSIL	2-5/8 NSILNRG	2-5/8	4	15 SLA	1-1/2	2-1/2	7-1/2	15 SLE	3LP
2-11/16 NSIL	2-11/16 NSILNRG	2-11/16	4	15 SLA	1-1/2	2-1/2	7-1/2	15 SLE	3LP
2-3/4 NSIL	2-3/4 NSILNRG	2-3/4	4	16 SLA	1-3/4	2-1/2	7-1/2	16 SLE	3LP
2-13/16 NSIL	2-13/16 NSILNRG	2-13/16	4	16 SLA	1-3/4	2-1/2	7-1/2	16 SLE	3LP
2-7/8 NSIL	2-7/8 NSILNRG	2-7/8	4	16 SLA	1-3/4	2-1/2	7-1/2	16 SLE	3LP
2-15/16 NSIL	2-15/16 NSILNRG	2-15/16	4	16 SLA	1-3/4	2-1/2	7-1/2	16 SLE	3LP
3 NSIL	3 NSILNRG	3	4	16 SLA	1-3/4	2-1/2	7-1/2	16 SLE	3LP