The 3F-HB is the ideal tool for performing those difficult facing, grooving, backfacing
and counterboring operations on work pieces too large to turn or too bulky to handle
safely.
This head has been redesigned to incorporate a reversing feature. The head can be used in either the forward mode (moving from the inside to the outside) or in the reversing mode (from the outside to the inside). This reversing function is accomplished by reversing the spindle and using the special shank lock mechanism built into the head.
The 3F-HB features a gear drive mechanism that generates a continuous feed rate. The standard unit has a feed rate of 0.003 per revolution. A fine feed model is also available with a feed rate 0.0015 per revolution. To prevent damage to the gear train, a specially designed detent clutch automatically disengages when a pre-set stop is reached or when cutting pressures become excessive.
Automatic feed is in the forward mode and is actuated by holding a knurled feed-ring. To return to starting position, a hex wrench is inserted in the end of the micrometer screw and manually reversed.
A 1-1/2-18 threaded back permits the use of any of the 1-1/2-18 threaded shanks and adapters shown in the Shanks & Adapters sections.
If service or repair is required, this head should be returned to your distributor or our factory.
| CODE NO. |
TOOL NO. |
THREADED BACK |
BODY DIA. |
HEIGHT | OFFSET OR TRAVEL |
BORING BAR HOLE SIZE |
CENTER DISTANCE BETWEEN HOLES |
CROSS HOLE DIAMETER |
FEED RATE |
|---|---|---|---|---|---|---|---|---|---|
| 10800 | 3F-HBD | 1-1/2-18 | 3" | 3-7/8" | 13/16" | 3/4" | 15/16" | 3/4" | .003 per rev. |
| 15800 | 3F-HBD F.F. | 1-1/2-18 | 3" | 3-7/8" | 13/16" | 3/4" | 15/16" | 3/4" | .0015 per rev. |
Criterion now offers a facing bar to
complement our 3F-HB boring and facing head. The bar is made of premium alloy steel with 4
flats and a shank ground to a tolerance of 0.0005. This bar can also be used in our
standard boring heads or in a lathe as a boring bar.
 |
|||||||
|---|---|---|---|---|---|---|---|
| CODE NO. | INSERT NO. | I.C. | T | R | H | INSERT SCREW |
SCREW WRENCH |
| 13440 | CPMT-3(2.5)1-1A GRADE C-2 | .375 | .156 | .015 | .173 | SN-59TX | T-15 |
| 13442 | CPMT-3(2.5)1-1A GRADE C-6 TIN-COATED | .375 | .156 | .015 | .173 | SN-59TX | T-15 |
| 13450 | CPMT-3(2.5)2-1A GRADE C-2 | .375 | .156 | .031 | .173 | SN-59TX | T-15 |
| 13452 | CPMT-3(2.5)2-1A GRADE C-6 TIN-COATED | .375 | .156 | .031 | .173 | SN-59TX | T-15 |