For indexing the teeth on a rack, the feed screw dial is used, for example, 16 diametrical pitch equals 0.196" which is the distance the table is moved for each tooth. Gear cutting operations are performed in much the same way except that an indexing fixture is necessary to hold the blank.

CUTTING BITS AND TOOLS

Cutting tools and holders for a shaper are very similar to those used on a lathe, even to the sharpening of the tool bits, but more top rake and less side clearance is desirable for the harder metals. Fig.1 illustrates how tools should be ground for various shaping operations. The angles and forms shown are general and will vary with materials and conditions.

FORMED TOOLS

When duplicate shaping is done, such as gear teeth, ratchet teeth, keyways, fillets, beads, grooves, etc, formed tools are required for uniformity, but these present the old problem of chattering cuts. The greater the cutting edge of tool in contact with the work, the greater chance of chatter occurring.

When conditions permit, it is advisable to rough out with a narrow tool before using the formed tool.

For internal shaping, such as keyseating a hole square or hexagon or any other shape, a long projecting tool is used. This should have the largest possible shank and minimum offset at the cutting end toobviate trouble due to "springing" (See Fig.1.)

RAM SPEEDS

Below is a table of ram speeds in feet per minute. These speeds are only applicable when using a 1,420 RPM motor and the motor pulley supplied with this machine, and are approximate.

CUTTING SPEEDS FOR VARIOUS MATERIALS

Select the cutting speed suitable for the work. Some typical cutting speeds are:-

Very high speeds should be avoided on the longer stroke, in order to avoid excessive vibration from the action of the ram travel.

ADJUSTMENTS

The ram, table, and cross slide bearings are provided with shims and gibs for making adjustments when necessary. The shims are 0.010" thick and are made up of five 0.002" leaves, held together with a light film of solder for convenience in handling, and easily sperated with a knife blade. The sliding vice jaw is also equipped with laminated shims for wear adjustment.

TAPER ROLLER BEARINGS

The crank gear and pinion gear shaft bearings have been properly adjusted at the factory, and should not be tampered with, unless end or radial play developes. If so, proceed as follows:-

A. Crank gear bearings. Run the shaper for about an hour to warm up the shaft (a temperature rise increases the length of the shaft). Remove the knurled knob from the shaft and detach the ratchet feed rod from the feed crank gear (located directly beneath the knob). Prise off the feed gear guard, after removing the two screws. Loosen the set screw in the collar adjacent to the spur gear and turn the collar until the bearings bind slightly when rotated; then back off to give free rotation with no end play. (Test this by moving the crank gear in a longitudinal and radial direction.) Tighten the set screw in the collar and re-assemble the parts in reverse order.

B. Pinion Gear Shaft Bearings. Run the shaper as explained above. Loosen the set screw in the bearing boss on the left side of the main frame. With a small pin punch held obliquely in one of the recessed holes in the adjusting collar, tap lightly with a hammer and turn the collar in a clockwise direction until the bearings bind slightly