Metal Machining

These vertical knee mills are equipped with vari-speed drive. The dove tail ways chromed, and the box ways are hardened and ground.

Head

To dissipate heat in the 3 HP motor driven head, a pair of high output fans is installed. This allows the machine to work demanding jobs for extended periods without damaging the motor, belts and bearings. A unique SHARP feature.

The motor shaft and Vari Drive pulleys are dynamically balanced, then hard-chromed this allow a vibration free milling even at high speed

Since the Vari-speed drive system is operated by sliding the Vari Drive pulley up and down the motor shaft. The motor shaft is therefore chrome-plated, and has an oil channel that is fed by a grease fitting on the lower end for self-lubricating purpose. This ensures the sliding motion is trouble free at all times. A unique SHARP feature.

The motor shaft that drives the pulley and the spindle is subject to a lot of lateral stress. A roller bearing is installed for the lower support of the motor shaft. A unique SHARP feature.

Beside swiveling 90 degree side to side, the head can also swivel up and down by virtue of a knuckle joint design. The new design developed by Sharp uses 6 bolts, 3 each side, that fitted into a circular T-slot milled at the inside of the over arm and secured by nuts from the outside. It secured the head tightly and offered high accuracy in milling operations.

A matched pair of super-precision ABEC-7 angular contact bearings supports the spindle. The quill is CNC-ground to a mirror finish, and then chromed to fit the housing. Together, they insure spindle run out of no more than 0.0004” TIR- the best in the industry.

Column, Table and Knee

Certified MEEHANITE castings are used for superior rigidity and better dampening of vibrations

Table and saddle backlash is controlled by a double-nut design that keeps the feed screw in contact with a pair of bronze nut at all times. A unique SHARP feature.
The end of the table and saddle are mounted with thrust bearings that pre-load the feed screw, eliminating endplay for precisely controlled lateral movement.

The end of the table and saddle are mounted with thrust bearings that pre-load the feed screw, eliminating endplay for precisely controlled lateral movement.

Instead of hand scraping the top of the knee ways for oil retention, the matching underside of the saddle is hand-scraped. This extra step avoids having chips and dirt embedded in the knee ways and damages the sliding area.
“Bridgeport-style” vertical knee mill
Specifications available upon request.