Grade 11 Maintenance of a pedestal drill The

Grade 11 Maintenance of a pedestal drill

The following guidelines can be used when using a pedestal drilling machine: • Visually check the main electrical switches, wiring • • and conduit (for any cracks, broken controls, etc. ) Verify that all guards are secure and that they function correctly Ensure that workspaces and walkways are clean/ unobstructed and that no slip hazards are present Confirm availability and condition of personal protective equipment Lubricate moving components such as the chuck, lightly according to manufacturer’s specifications Mechanical Technology Curriculum Coordination & Support

• Use moisture penetrating oil spray on exposed metal surfaces and wipe them down with a cloth to prevent rust • Check the availability of specific tools for the pedestal drill (spanners, Allen keys, chuck keys, etc. ) • Use a dial indicator to check the run-out of the spindle is within the manufactures specifications • Check the floor for oil contamination • The chuck key must be chained to the drill press to prevent it from being flung into the operator should it be negligently left in the chuck before or after drilling Mechanical Technology Curriculum Coordination & Support

• Inspect the belts for wear, cracks and stretching, and replace them according to manufacturer’s specifications • Ensure that the drive belt is correctly tensioned • Check the condition of the rack-and-pinion mechanisms and lubricate if necessary • Ensure that the cuttings and waste material is removed from the working surface, this includes the T-slots on the table • Inspect Morse taper sleeves for burrs/scratches. Remove raised metal using an appropriate reamer • Check the security of the machine mountings to the floor or base block, and tighten them if they are loose. Mechanical Technology Curriculum Coordination & Support

Lubrication • The only parts on a pedestal that needs lubrication is the column where the table adjust up and down and the spindle holder. Rusted spindle and column Mechanical Technology Curriculum Coordination & Support

Lubricating column and spindle Mechanical Technology Curriculum Coordination & Support

Problem and Solutions Problem Probable Cause Solution Noisy operation Spindle dry Remove the spindle and lubricate Excessive wobbling of the spindle Bearing failure or worn spindle shaft due to the lack of lubrication Replace the shaft, spindle or bearing The drill tip is burning, smoking or screeching Insufficient lubrication Lubricate drill bit while drilling The temperature of the spindle holder is too high Insufficient lubrication Lubricate the spindle holder Mechanical Technology Curriculum Coordination & Support

Overloading • Extreme heat may cause the motor to overheat so use intermittent or on and off, operations to keep the motor running cool. . • Do not press too hard on the material when drilling so that the motor starts to slow down. It will cause it to overheat. • Overloading also may cause the drill bits to break Mechanical Technology Curriculum Coordination & Support

Mechanical Technology Curriculum Coordination & Support

Friction • Most friction happens on the spindle where the v-belts are running. • The bearings on the pulleys also run the risk of failure if the tension on the belts are too tight. • Bearings need to be well lubricated at all times. Mechanical Technology Curriculum Coordination & Support

Mechanical Technology Curriculum Coordination & Support

Cutting Speed Formula for cutting speed S=πx. Dx. N Where: S = cutting speed in mm/sec or m/min D = diameter of drill bit N = revolution per second Mechanical Technology Curriculum Coordination & Support

Example • The cutting speed for mild steel is 30 meters per minute. Calculate the speed of the machine spindle if you need to drill a hole of 12 mm Mechanical Technology Curriculum Coordination & Support

Step 1 • Mechanical Technology Curriculum Coordination & Support

Calculate: • Mechanical Technology Curriculum Coordination & Support