SF drill bushings are replaceable bushings generally used with a liner bushing and lockscrew. Use SF bushings when you expect to replace bushings during the tooling's lifetime, or to switch bushings to perform multi-step operations with the same tooling. SF bushings combine the benefits of older S-type slip-renewable and F-type fixed renewable bushings: one side of SF drill bushings feature a lockscrew recess for fixed mounting; the other has a locking recess that allows the bushing to slip down, then rotate to lock in place. S and F types are now obsolete, and combination SF drill bushings will be supplied at no extra charge.
To order a specific standard SF drill bushing, select the basic part number below and add the desired ID drill size (as a 4-place decimal inch) on the Price & Availability screen. See Technical Information tab for Standard Drill Sizes. Standard prices apply only to bushings with a standard inch, number, letter, or metric ID size within the stated range (either ground or unground OD). Long bushings with ID sizes marked * are counterbored according to ANSI standards for proper drill-bearing length.
Example standard bushings:
SF-20-16-.1250 1/8" ID (.1250)
SF-20-16-.1772 4.50mm ID (.1772)
These replaceable bushings are generally used with a liner bushing and lockscrew.
Standard ID Tolerance:
From #80 to 1/4" +.0001/+.0004
Over 1/4 to 3/4" +.0001/+.0005
Over 3/4 to 1-1/2" +.0002/+.0006
Over 1-1/2 to 2-3/4" +.0003/+.0007
Reamer ID Tolerance (Special):
From #80 to 1/4" +.0005/+.0008
Over 1/4 to 3/4" +.0006/+.0010
Over 3/4 to 1-1/2" +.0008/+.0012
Reamer bushings have a different ID-tolerance range than drill bushings. To special-order bushings with the reamer ID tolerance shown here, add "-REAMER" to the part number:
Standard OD Tolerance:
3/16 to 1" 0/-.0002
1-3/8 to 1-3/4" 0/-.0003
2-1/4 to 5" 0/-.0004
Extremely long bushings with a small ID size (marked with an asterisk * in the tables below) are counterbored according to ANSI standards for proper drill-bearing length to eliminate binding and heat buildup. Add "-NCB" for applications that require these bushings without a counterbore:
1144 Stressproof steel, heat treated to achieve Rc 62-64 ID hardness. Other materials are available by special order. DFARS and RoHS compliant.