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					Drills
• Used to create holes in metal and plastic parts • May be portable or mounted on a workbench or the floor

DIFFERENCE BETWEEN Hand Tools AND Power Tools But they are Both in Drills
• Hand tools Have no power source, other than the physical force applied by the user. Hand- tools include anything from axes to hammers, and screwdrivers to wrenches.

• Power Tools Require a non-human power source to function properly--e.g. External (electricity, compressed air, etc.) or Internal (battery pack, internal combustion engine, etc.).

Drilling operations…
• Operations that can be performed in a drillin g machine are       Drilling Reaming Boring Counter boring Countersinking Tapping

Your Safety 101
• 1. Own and wear safety glasses. 2. Do not wear loose fitting clothing. 3. Wear clothing that will cover and protect your body, but not get caught up in the moving parts of the drill. 4. Use a dust mask if needed. 5. Hearing protection never hurt anyone. 6. Loose fitting gloves might get caught by moving devices.

Always
• Always make sure the chuck key is removed before proceeding.

Proper Technique:
1. Maintain your drill and bits 2. Clamp and secure whatever your working on as a general rule. 3. Mark the center of the hole or use a center punch to mark it. Then place the drill in the center of the hole. 4. Predrill holes for woodscrews. 5. Start slowly and slowly increase speed. 6. Vary the pressure and don’t let the drill bind. 7. Don’t force the drill, let the machine do the work. 8. Slower speeds for thicker wood and high speed for metals. 9. Withdraw the bit often while drilling to remove chips. 10. Brush these away, blow on them and they could end up in your eyes. 11. Use a side handle and hold the drill firmly with both hands. 12. Take your time

Portable Drill / Drill Press Safety Precautions
• Check carefully for loose power cord connections and frays or damage to the cord. Replace damaged tool and extension cords immediately. • Be sure the chuck is tightly secured to the spindle. This is especially important on reversible type drills. • Tighten the bit securely as prescribed by the teacher. The chuck key must be removed from the chuck before starting the drill. A flying key can be an injury-inflicting missile.

• Check auxiliary handles, if part of the tool. Be sure they are securely installed. Always use the auxiliary drill handle when provided. It gives you more control of the drill, especially if stalled conditions occur. Grasp the drill firmly by insulated surfaces. • Always hold or brace the tool securely. Brace against stationary objects for maximum control. If drilling in a clockwise -- forward -- direction, brace the drill to prevent a counterclockwise reaction. • Don't force a drill. Apply enough pressure to keep the drill bit cutting smoothly. If the drill slows down, relieve the pressure. Forcing the drill can cause the motor to overheat, damage the bit and reduce operator control.

Portable Drill Safety Precautions

Power Drill
• Do: – Keep bit out of drill until just before use – Make sure bit is properly locked in securely – Secure item to be drilled on workbench – Drill straight down or horizontally away from your body – Allow bit to pass completely though item being drilled – Use auxiliary handles
2006

• Don’t: – Walk with bit in drill – Point drill at others OR any part of your body – Use screwdriver heads on drill – Use wrong bits
• Size • Type (wood bit versus metal)

Alternatives to the Drill Press
• There are many ways to drill holes in material
– You could use a electric plug-in or cordless hand drills.

Drills – Electric Corded
• Used for drilling metal and wood – Key type chuck
with ½” capacity – has auxiliary handle for more stability and is variable speed reversible (VSR)

• Used for drilling metal and wood – Keyless type
chuck (hand only) with 3/8” capacity – is variable

speed reversible (VSR)

• Used for drilling metal and wood – Key type chuck
with 3/8” capacity – it is a right hand close quarter design for getting into hard to reach places and is variable speed reversible (VSR)

Drills – Cordless
• Used for drilling metal and wood – Keyless type
chuck (hand only) with ½ ” capacity – Has torque adjustable driver capability and is variable speed reversible (VSR) 18 Volt rechargeable battery packs.

• Used for drilling metal and wood – Keyless type
chuck (hand only) with 3/8 ” capacity – Has torque adjustable driver capability and is variable speed reversible (VSR) 14 Volt rechargeable battery packs.

Air Drill

Power and rotating speed can be set to match the job at hand–used to drill holes, grind, polish, and clean parts

Drills

Tool Holding devices
• The different methods used for holding drill in a drill spindle are • By directly fitting in the spindle hole. • By using drill sleeve • By using drill socket • By using drill chuck

Work Holding Devices

Chuck Key

Used to tighten a drill bit in the drill chuck

Portable Electric Drill

Size of a drill is an indication of the capacity of its chuck–common sizes are 1/4”, 3/8”, and 1/2”

Bits
• Drills use drill bits, or twist drills, to drill holes in metal and plastic parts • Made of carbon steel or high-speed steel • High-speed steel is better because of its resistance to heat

Drill Bit

Tool Nomenclature

Drill Bits for the Drill
• You may use a variety of drill bits

Drilling And Drills

Types of drills – Twist drill: most common drill – Step drill: produces holes of two or more different diameters – Core drill: used to make an existing hole bigger

Drill fixed to the spindle
Drilling operations
Drilling Centre Hole

Drilling Deep Holes
Drilling Thin

Material
Drilling Pilot Hole

Operations in drilling machine

Operations in drilling machine

Work Holding Devices
• 1. Machine Table Vice

Work Holding Devices
• • • • • • Step Blocks Clamps V-Blocks Angles Jigs T- Slots Bolt

Alternatives to the Drill Press
• There are many ways to drill holes in material
– You could use a manual hand drill.

Drill Press
• A drill press is a vertically mounted variable speed drill motor used for drilling precise holes.

Drill Press
• Drill press consists of base, table, head, arbor, spindle, chuck
HEAD
ARBOR CHUCK SPINDLE

TABLE

BASE

Drill Press Parts
• It is important to know the parts of the drill press for its operation.

Basic Terminology
• Fixturing
– Vise – Clamping Kit
• • • • • T-slot nuts Flange nuts Coupling nuts Step blocks Step clamps

– V-blocks

Drill Chucks
• Drill Chuck Types
–Key-Type Chuck –Keyless Chuck –Pin Chuck –Sensitive Drill Chuck

Drill Chucks
• Key-Type Chuck
– Used to hold small drills, usually under ½ inch in diameter. – Holds only straight shank drills and tooling – i.e. – reduced shank drill bits, reamers and countersinks – Has three jaws that open and close simultaneously against straight shanks using a drill chuck key.
Reduced Shank Drill Bit Chuck Key

Drill Chucks
• Keyless Chuck
– Used to hold small drills, usually under ½ inch in diameter. – Holds only straight shank drills and tooling – i.e. – reduced shank drill bits, reamers and countersinks – Has three jaws that open and close simultaneously against straight shanks using firm hand pressure only – Quicker loading and un-loading of tooling compared to key-type chucks

Note: If chuck is not tight enough drill bit will be damaged resulting in deep groves in the bit shankand possibly making the bit off center.

Drill Chucks
• Pin Chuck
– Used to hold very small drills, usually 0 to 3/32 inch in diameter. – Has 3 interchangeable collets – Fits in a larger collet or drill chuck

Drill Chucks
• Sensitive Drill Chuck
– The sensitive drill feed/chuck provides fingertip control when drilling very small holes on a drill press or milling machine. – This tool bypasses the machine’s coarse quill feed, giving the operator better feel and control of the feed rate. – Breakage of small diameter drills is greatly reduced and the tendency for drill “walking” is minimized. – Has a ½ inch straight shank that will mount in a collet, chuck or toolholder

Changing the Drill Chuck
• To remove the drill chuck insert the drift as shown – slot in spindle • Tap the wide end of the drift with a hammer/mallet and catch the drill chuck so it does not hit the table • Put in the new chuck or tapered drill bit so the tang lines up with the slot where the drift was inserted in the spindle

Spindle Drift Slot

Tang

Drill Press Safety
• Wear eye protection at all times.
• Do not operate the drill press until you have passed all safety requirements.

Drill Press Safety
• Always make sure that the stock is securely clamped whenever clamping is necessary. Do not try to hold small pieces of stock by hand. • Place the long end of the piece being drilled to the left so it will hit the post and not the operator should the material slip and start rotating.

Drill Press Safety
• Always remove the chuck key immediately after installing a tool. • Never wear gloves when operating the drill press. They may get caught.

Drill Press Safety
• Do not feed the drill faster than it can easily cut. Do not force the drill. • Back out frequently on deep cuts, to clean and cool the bit.

Drill Press Safety
• Use care in reaching around the machine. • Never remove chips with your fingers. Keep them away from the revolving tool.

Drill Press Safety Rules
1. Set depth of cut to avoid drilling into the drill press table. 2. Generally, the softer the material you are drilling and the larger the twist drill or bit, then the slow the rpm should be set. The harder the material being cut and the smaller the twist drill, then the faster the rpm should be set. 3. On large floor model drill presses, set the rpm while it is running using the speed adjustment hand wheel. On many of the bench-top models, set the rpm while the drill press is stopped and unplugged using the pulley and belt. 4. Use a coolant when drilling metal. 5. Feed the drill so a steady stream of chips flow from the flutes of the twist drill. Metal should produce a continuous ribbon as its chip.

Drill Press Safety Rules
6. If chips become clogged in the flutes of twist drills, then remove the drill from the hole. 7. Clamp stock for specialty bits such as Forstner bits, speed bores, hole saws, expansion bits, etc. 8. Generally, use as slow a speed as possible for specialty bits, but make sure the cutter does not simply rub the stock and overheat. 9. Clamp irregular stock. 10. Always secure the drill in the chuck. 11. Always remove the chuck key before operation.

Drill Bits
• Choose the proper bit for the material to be drilled: wood vs metal, high speed vs low speed.

Drill Press Setup
• Always back up the material to be drilled to protect the table and to prevent tear out of the material on the back side.
TABLE BACKER BOARD

Drill Press Setup
• Clamp thin or sharp stock in case the bit grabs it and it becomes a dangerously sharp spinning object.

Drilling Operations
• Securing the Work Piece
Be sure the work piece is securely fastened to the work table (clamps mounted on the wall between drill presses) The importance of securely mounting the work to the table cannot be over emphasized. Injuries can occur by hand holding the work or not clamping the vise to the table – Note: Make sure the vise handle is facing left when mounted to the table, this way, if the drill bit catches and spins the vise, the handle will hit the drill press column and not the operator Vises are located on the work table by drill presses Clamps are located on the wall between drill presses

Drill Press Use
• Hold down on the workpiece to prevent it from coming up with the drill bit when you let up on the arbor. • Turn off the machine but do not leave it until it has stopped completely. Clean off with a bench brush, not your hand (splinters/slivers).

Drilling Operations - Using A Vise
• Note: Always make sure you are drilling a workpiece within the jaw clamping area of the drill press vise. Never drill a hole in a workpiece hanging out of the drill press vise.

YES

NO

Drilling Operations – Spotting A Hole
• It very important that you have your hole location marked on your workpiece with the use of a center punch, center drill or spot drill

Center Punch

Center Drill

Spot Drill

Drilling Operations – Drill Hole To Size
• After the hole has been marked and spotted, proceed with drilling the hole to size. If you are drilling a hole larger than ¾ inch, drill through with a size between 0 and ¾”. Make sure you use cutting fluid from the white cups throughout the shop and keep the chips out of your hole and off your drill bit with the blue chip brushes – shown below

•

• NOTE: Do NOT use cutting fluid on PLASTICS – Use soapy water

Drilling Operations – Countersinks
• A tool used to produce a conical enlargement of the end of a hole.
– Used as a chamfering or deburring tool – 1/32 to 1/16 is sufficient for most holes. Used prior to tapping or reaming, protects hole from burrs and nicks. – Used for recessing the head of a machine screw (Flat Head). – 82 degree single flute is the most common countersink used for this purpose. – The cutting speed used when countersinking should be slow enough to avoid chattering. A good starting point would be 1/3 the drill speed.

Countersunk For A Flat Head 82 Degree Single Flute Screw

Ok Make a Hole in Something
• But not your Safety


				
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