Portable Power Tools Unit 14 Page 180

1. Portable Power ToolsUnit 14Page 180

2. Introduction • Portable Power Tool: A tool that can be held in the operators hands, but is not hand powered. • Four common sources of power. Battery Electricity Pneumatic There are advantages and disadvantages for each type of power source. Engine

3. 1. Electrical Power • Very popular • Usually use 120 V, 1ø power Disadvantages • Must stay connected to power cord. • Hazards of electricity Advantages • Unlimited power • Many different types of tools. Extension cord must be proper size and in good condition.

4. 2. Pneumatic Becoming more popular where compressed air is available. Disadvantages • Air must be clean and dry. • A blast of high pressure air can embed objects in the skin or eyes. • Air hose more difficult to manage than electric cord. Advantages • Smaller dimensions for torque produced • Torque easily adjusted (changing pressure) • Popular in hazardous environments All common tools can be air driven. • Drills • Ratchet drives • Sanders

5. 3. Battery New technology in batteries has made battery powered tools the first choice for most professionals. Advantages • Portability • Sealed unit • No electrical circuit hazards. • Can be used with a wider variety of tools when compared to pneumatic. Disadvantages • May be less torque • Must have a charged battery to use. • Batteries can have a short useable life and are expensive to replace.

6. 4. Engine Popularity is gaining with the resent invention of lighter weigh engines. The elimination of 2-cycle engines will require a redesign. Advantages • Portability • No air hose • No extension cords • No battery Disadvantages • Must be used in open environment. • Disadvantage of engine maintenance. • Safety concerns of gas engines. • Usually only large sizes.

7. Portable Power Tool Safety • Use GFCI protected circuit. • Use three-wire electrical source if tool housing is metal or partially metal and not double insulated. • Insure blades, bits, and other cutting devices are clean and sharp • Support work carefully • Keep all tools clean and free of dirt. • Keep tool vent holes clean. • Wear appropriate personal protection • Avoid or use extra care when working in wet areas • Do not force tools to work. • Hold power tool firmly and insure your have control at all times. • If the condition of the tool is in doubt, do not use. • Announce to co-workers before starting a tool. • Lay tool down correctly • Take any faulty tools out of use and insure they are fixed before returning.

8. Nail Guns • Popular because they are fast and efficient. • Produce enough force to drive 2 - 3 inch nail into dense wood. • Accelerate nail to 1,000 feet per second. • Four types • Brad • Framing • Finishing • Staple • Power • Pneumatic • Electric • Fuel cell • Fasteners • 1/4 inch brad and staples up to 4 inch nails.

9. Portable Drills • Size • Size based on capacity of chuck • Wattage difference within chuck size • Common sizes are 1/4, 3/8, 1/2 & 3/4 inch • Construction • Case will be metal, non-metallic or a combination. • Wide variety • Options • Variable speed • Reversing • Extra handle • Hammer action • Torque clutch • Depth stop • Drill press attachment • Keyless chuck • Screw chuck

10. Portable Drill-cont. Always center punch location of hole. Drill pilot hole before using a large drill bit. • Use many different types of bits., • Drill holes and slots • Use to drive screws • Sanding disc and wire wheels can be used. • Must be careful to not exceed the duty cycle

11. Portable Drill Safety • Inspect bit before using • Tight chuck using more that one hole • Center punch metal before starting to drill • Hold material securely • Do not exceed rpm of bit • Use even pressure • Ease off pressure when drill starts to break through • Don’t bind the drill bit • Stand in a balanced position • Remove the drill from the chuck when finished • Store portable drill and bits in case or designated storage rack.

12. Sander • Three common types • Belt • Disc • Pad

13. Sander-cont. • Portable power sanders to the same job as hand sanding--just faster. • Normally sand with the grain • Exceptions • Uneven boards • Rough surface • Removing difficult finishes • Different grit paper available • Coarse grit = rapid sanding, rough surface • Fine grit = slow sanding, smooth surface

14. Belt Sander • Very versatile • Popular for rough sanding because of aggressive action with coarse belts. • Can produce smooth finish with fine belt. • Some belts are not bi-directional. • Dust collection system highly recommenced.

15. Belt Sander Safety • Wear appropriate PPE • Check cords and switches • Install appropriate belt for the desired cutting action and finish • Lay sander on side when not in use • Empty dust bag frequently • Always start sander above the surface • Use two hands at all times • Keep machine in motion • Lift off material while still running • Never sand on the drums

16. Disc Sander • Machine can use sanding disc, grinding wheel and wire brush interchangeably. • Must follow manufacturer's recommendation for use. Switch Lock Power Cord • Several tools with this right angle design look the same. • Some are sanders, some are sanders/grinders and some are grinders. • Big difference in construction • Grinders are much heavier construction. Motor Housing Tool Rest Handle Sanding Wheel Switch Vents Sanding Disc Handle Guard

17. Disc Sander Safety • Select the sanding wheel appropriate for the material being sanded. • Aluminum oxide = wood or metal • Flint paper = wood only • Use the appropriate guard • Wear appropriate PPE. • Grip machine firmly in both hands before starting • Do not force the machine to work • Lay the machine on the tool rest, not the disc. • Be aware of, and plan for the direction of material being discharged by the wheel. • Hold small pieces in a vise.

18. Disc Grinder Safety • Wear face shield plus safety glasses. • Check grinding wheel for cracks before using • Only use wheel designed for that machine. • Never use grinding wheel that is less than 1/2 original diameter. • Secure small pieces in a vise • Do grind near combustibles • Hold the machine with both hands at all times. • Always be aware of were the discharged sparks and grit is going.

19. Pad (Finishing) Sander • Multiple pad movements possible. • Reciprocating • Circular • Orbital • Random • Slower cutting Switch Lock Handle Motor Housing Power Cord Handle Switch Paper Clamp Paper Clamp Sand Paper Pad

20. Pad Sander Safety • Use appropriate PPE. • Use correct size of paper. • Disconnect power when changing paper. • Only use light pressure when sanding

21. Portable Saws • Portable saws can be divided into three categories. • Sabre • Reciprocating • Circular

22. Sabre Saws • A compact saw that is very useful for cutting curves. • Designed for wood, but will cut thin metal. • Blade uses reciprocating motion. • Can be used for blind cuts. • Base may tilt for cutting bevels. Switch Handle Power Cord Motor Housing Blade Retention Screw Base Tilt Lock Base Blade Toe

23. Sabre Saw Safety • Wear appropriate PPE • Select correct blade for job. • Width of blade determines minimum radius • Secure material being cut • Let saw determine feed rate. • Must maintain downward pressure on the saw when cutting.

24. Reciprocating Saw Motor Housing • Usually heavier duty that the sabre saw. • Longer stroke on the blade. • Many different types of blades. • Designed for wood and metal. Switch • Does not cut as precise as sabre saw. • May be multiple speed. • Can be used to make a blind cut. • Very popular for demolition work. Shoe Switch Lock Handle Cord Blade Blade Retention Screw Vents

25. Reciprocating Saw Safety • Wear appropriate PPE. • Select the correct blade for the job. • Select the correct speed. • Be careful not to bind, pinch or crowd the blade. • Hold the shoe against the work at all times. • Do not wear loose fitting clothing.

26. Circular Saw • Most popular saw for carpentry work. • Different size and types of blades are available. • Can be used for wood and metal. • Available in direct mount, right and left hand and worm drive.

27. Circular Saw Safety • Wear appropriate PPE. • Use face shield + safety glasses • Use blade appropriate for work. • Support work correctly. • Disconnect the power when adjusting the saw. • Adjust blade for depth so that only 1/4 inch or the depth of one tooth extends through the work. • Hold saw in both hands. • Start the saw before contacting work. • If the saw stalls, back out of kerf. • Watch the line ahead of the saw. • Near the end of the cut reduce the pressure. • For ripping use the ripping guide attachment or clamp a straight edge to the work.

28. Circular Saw Capacity • Capacity of portable circular saws at 45 degree bevel and straight.

29. Router Cord Switch • Routers are used for specialized jobs such as ornamental shapes, rabbets, dadoes, hinges, etc. • Router bits turn at high speeds. • May have several attachments. • Must use guide to complete straight cuts. • May be mounted on a table. Depth of Cut Adjustment Depth of cut Scale Handle Collet Base

30. Router Safety • Wear appropriate PPE. • Secure work. • Insure router is unplugged before installing bit or setting depth adjustment. • Always inspect bit for condition and sharpness. • Install the appropriate bit. • Insure bit shank is fully inserted into collet. • Carefully set depth of cut. • Set base squarely on work. • Always use both handles • Feed router into work at correct speed.

31. Questions