STANDARD SIZES:Standard sizes in a given I.D. range are sizes listed in the decimal equivalent chart either as a fraction, number or letter size. Any other decimal or millimeter size within a given range is considered special and will be priced accordingly.

TO ORDER:
Specify Type and "Reamer Bushing". Reamer bushings will be furnished with correct tolerance on all fraction, number, letter, and all decimal sizes. (Priced as specials.)

COUNTERBORE:
Bushings with small holes are counterbored leaving correct drill bearing, to facilitate chip removal and lubrication. (Refer to catalog page 47)

NO COUNTERBORE:
Bushings normally counterbored may be ordered without counterbore by specifying "No Counterbore" or using abbreviation "N CB". (Priced as specials.)

CONCENTRICITY:
(Total indicator reading) Bushings 1/8" to 1" I.D. - Concentricity 0" to .0003" (Max.) Other sizes - Concentricity 0" to .0005" (Max.) On counterbored bushings above tolerances will be met at the drill exit end.

STEEL:
Our bushings are manufactured from either C1144 Stressproof steel or other high carbon steels known for their durability and stability. Special materials such as bronze, tungsten carbide, 52100 steel, 300 and 400 Series stainless steel plus A2, D2, D3, M2 and M4 tool steels are also available.

HARDNESS:
Rockwell C 62 - 64.

APPLICATION DATA
The slip fixed renewable bushing is used in conjunction with a liner or headliner (L or HL). The unique design of this versatile drill bushing offers the combined features of both the slip and the fixed renewable bushings (S and F). It is recommended for long production runs where more than one operation is performed in the same hole, such as drilling, then reaming or counterboring. There is a slot milled in the knurled head of the slip fixed renewable which enables a lockscrew or clamp to hold the bushing in place or easily remove it.

RADIUS:
All bushings feature a blended radius at drill entrance unless otherwise specified.

INSTALLATION DATA
The slip fixed renewable drill bushing is used with a liner, Type L or HL, drill bushing. The body O.D. is ground to provide correct slip fit with the liner. See installation data for the liner bushing on catalog page 15. The slip fixed renewable drill bushing is held in place by a lock screw or clamp.

NOTE:
Chip clearance: Due to the abrasive action of metal particles, sufficient clearance should be provided between the drill bushing and the work piece to allow for removal of chips. Careful consideration of this point will aid in producing accurate holes. (A rule of thumb is, the greater the clearance the greater the chance of error.)
Example: The recommended chip clearance for metals producing small chips, such as cast iron, equals one-half the drill diameter. The recommended chip clearance for metals producing long chips, such as cold-rolled steel equals one to one and one-half times the drill diameter.

Maximum Accuracy:
Use drill bushings of different lengths to obtain the combined advantages of adequate chip removal and precise accuracy.
Example: Use a drill bushing that is short enough to provide proper chip clearance during the drilling operation. Next, use a renewable bushing long enough to contact or closely approach the work piece for the reaming operation.