1. CH 6.5
Electric Power Tools

2. Introduction (1 of 2)
Tools and equipment are very important to an efficient and effective shop operation.
Provide means for work to be undertaken on vehicles
Purchase, use, and maintenance is very important to overall performance of any shop.

3. Introduction (2 of 2)
Always use tools and equipment the way they are designed to be used.
Identify the most effective tools to do the task.
Inspect the tool before using it.
Use it correctly.
Clean and inspect it after you use it.
Store it in the correct location.

4. Drills and Drill Bits (1 of 6)
Corded drill
Has cord that is plugged into electrical supply
Operating voltage depends on country’s supply
Good choice when moderate power is needed
Cordless drill
Uses its own internal batteries
Doesn’t drill large holes through hard metal
Versatile but limited to amount of work it can do

5. Drills and Drill Bits (2 of 6)
Drill bit that fits into chuck of drill marked on body of drill or chuck
Some drills have 2 operating speeds.
Drill bits come in many closely spaced sizes and types.

6. Drills and Drill Bits (3 of 6)
Twist drill
Has a point with cutting flutes that form a common angle of 118 degrees
Body, which usually has two spiral grooves, and its shank are gripped in jaws of drill chuck.
A good all-purpose bit for drilling metals
Drill chuck
A device for securely gripping drill bits in a drill

7. Drills and Drill Bits (4 of 6)
Drill press
Allows for accurate drilling with more control than is offered by a portable drill
Can feed the drill bit at a controlled rate
Can be set to run at different drilling speeds

8. Drills and Drill Bits (5 of 6)
Morse taper
A system for securing drill bits to drills
Size changes according to drill size.
The shank of drill bit is tapered and looks like tang of a file.
A quick way to change drills without constantly adjusting the chuck

9. Drills and Drill Bits (6 of 6)
Multi-fluted tapered hole drill
Used when there is already a hole drilled in sheet metal that needs enlarging
A drilling speed chart is usually supplied with the drill press and should be kept for reference.
Drilling metals is also best performed with the aid of lubricant.

10. Bench and Angle Grinders (1 of 9)
Power grinders come in different ranges of sizes and speeds.
Size is normally determined by diameter of largest grinding wheel or disc that can be fitted to it.
Some are fixed to a bench or pedestal.
Others are portable.

11. Bench and Angle Grinders (2 of 9)
Grinding wheels and discs
Usually have a maximum safe operating speed printed on them
Appropriate eye protection must be worn when grinders are being used.
The wheel guards and shields must be correctly and firmly in place.

12. Bench and Angle Grinders (3 of 9)
Bench grinder (pedestal grinder)
Normally has a rating with size of grinding wheel it can take
Wheels range from coarse to fine, and also in hardness.

13. Bench and Angle Grinders (4 of 9)
Usually needed when bench grinder is not appropriate
Uses discs rather than wheels
During grinding, the face of the disc is used instead of the edge.
Can throw sparks many feet
Use hearing protection.

14. Bench and Angle Grinders (5 of 9)
Straight grinder
Takes conventional grinding wheels but is limited to a diameter of about 4.75″
The grinder has a long shaft that moves the grinding wheel away from the motor.
Handy to get into recessed areas

15. Bench and Angle Grinders (6 of 9)
Hand-held cut-off wheels can be powered by electricity or air.
Use a special thin grinding disk to enable them to cut
Use the edge of the wheel for cutting
Useful for jobs that cannot be reached with a hacksaw

16. Bench and Angle Grinders (7 of 9)
Using bench grinders
When grinding metal, it must not be allowed to overheat.
Stop and dip metal regularly into water pot attached to the base of the grinder.

17. Bench and Angle Grinders (8 of 9)
Using angle grinders
Uses an electric motor to drive an abrasive disc at high speed
The turning disc is used to grind or cut metal.
The grinder size relates to the diameter of the cutting disc.

18. Bench and Angle Grinders (9 of 9)
Using angle grinders
Sanding discs and wire wheels can be fitted on the grinder.
An extra handle can be attached to the grinder head.
The abrasive disc, or cutting wheel, is attached to the grinder by a flange and nut.
Always use edge of the disc rather than the face.

19. Summary (21 of 30)
Power tools can be stationary or portable, corded or cordless, and powered by electricity, batteries, compressed air, a propellant, or a gasoline engine.
Drills are designed to drive a drill bit into metal (or other material) to create a hole; check drilling speed charts for proper drilling speed.

20. Summary (22 of 30)
Portable grinders are designed to grind down metals, but can also be fitted with a cutting disc to cut sheets of metal.
Air tools use compressed, pressurized air for power; types include the air impact wrench, air ratchet, air hammer, air drill, and blowgun/air nozzle.

21. Credits
Unless otherwise indicated, all photographs and illustrations are under copyright of Jones & Bartlett Learning.