C-2 Portable Power Tools Flashcards
Powder-actuated tools
use gunpowder to fire a fastener int either lumber or wood
Low - Velocity powder actuated tool
contains a “captive piston” meaning when the cartridge is fired, the force of the explosion acts first on the piston then fires the fastener to drive into meterial
safety features of LV tools
- captive piston
- built in device that prevents device from firing
- two distinct sequential actions required before tool can be fired
- method for verifying the power level
High Velocity tools
Direct acting tools they have no pistons and the fastening pins travel at speeds of 150-460 feet per second
Methods of Propulsion
- impact
- contact
- co-acting
Impact
type of fastener
gap between piston and fastener. fastener is against the work surface. tool is fired and piston travels down barrel to strike fastener
Contact
piston is in contact with fastener which then is in contact with work serface
co- acting
piston and fastener are not in contact with work surface
- piston and fastener reach certain speed before hitting work surface
Threaded
Bolting an object after a fastener has been driven
headed
for fastening an object to concrete or steel
eyelet
for holding lightweight objects such as suspended ceiling
Center Punch test
used to determine if a material is suitable for fastening with a powder actuated fastener.
try and punch fastener into material should make distinct dent
Minimum thickness of concrete for fastner
must be three times the penetration of fastener
- must be 75mm from edge of concrete
- do not fasten on joints
- spaced more then 3 inches
Spalling
when fastener blows out bits of concrete from point of entry
how to prevent spalling
use washer
- reduce shank diameter of fastener
- reduce shank length of fastener
- reduce cartridge strength
things to consider when fastening to steel
- must be at least 50mm or (2”) away from weld or joint
- must be at least 13mm (1/2”) away from edge of steel
- fasteners should be installed 1 inch apart
Gas Powered chainsaw
- most common
- portable
disadvantages is fumes
Electric powered Chainsaw
sometimes used in enclosed spaces where fumes are to hazardous. not as powerful as gas saws
Battery powered chainsaw
- use large rechargeable batteries 40v
- can be used when no electric power is available
Pneumatic chainsaw
air driven chainsaw that requires an air compressor. common in bridgework
Components of chainsaw
starter throttle lockout throttle fueltank chain oil tank bucking spike chain brake
Kickback
occurs when rotating chain momentarily hangs up on an obstruction and throws saw back on user
Chain cuts
chain still spins after finger is let off throttle keep eyes peeled and stay vigilant
Hammer Drill
mechanical action makes the bit vibrate into the concrete
Rotary hammer
delivered by a piston-like device, delivers blow ten times harder then hammer drill
Bull Point bit
has sharp point fro breaking up concrete
Chisel bit
for breaking up concrete and other hard materials
scaling or wide chisel bit
has wider blade then chisel bit
digger bit
slightly wider bit used to dig or trench
asphalt cutter
used win demo hammer when removing asphalt
- operator can make long straight cuts
tamping bit
can pack down soil or loose gravel
Handheld saw
saw is brought to the material and held by hand
bench top saw
saw is mounted on surface
walk behind saw
operator steers the saw while walking
Abrasive disks
for handheld concrete or metal cutting disks
sub abrasive disks
use diamond impregnated metal blades or cubic boron nitride blades. used to cut tile, stone, asphalt, concrete
angle grinder
used to smooth concrete surfaces and to cut off exposed steel
types of metal grinding wheels
ferrous metal wheels (cast- iron, steel)
non ferrous metal wheels ( brass, copper, aluminum)
cutt off wheels (zipdisks)
size of router
two factors ( horsepower of the motor and the maximum shank diameter
Collet nut
holds the bit securely to the router
guid bearing router
many bits equipped with bearings that guid bit a certain distance from material.
straight flute bit
cuts plow or dado in wood
Laminate bit
used to trim finished edge of laminate counter tops can also be used of edges of wood
Chamfer bit
buts a 45 degree bevel on edge of board
Bullnose bit (Router)
used to round the edge of boards and trim
Ogee bit
ogee bit is used to put an ogee on the edge of a board ogee shape curves one way and then the other
dovetail bit
using a jig can make a decretive and strong dovetail joint
cove bit
used to but cove (inside curve)
Router bit speed
Bit Diameter Max Router speed up to 25mm -> 24000 rpm 25-32mm -> 18000 rpm 32-57mm - > 16000 rpm 57 - 89mm -> 12000 rpm
templates
used with routers to cut specific holes
guide bushings
when using a guide bushing the gap between the router and the outside edge of bushing must be considered when making the template
Belt sanders
used to smooth faces of wood. measured by the width of of sander.
Disk sanders
- used for shaping curved surfaces
- or sanding edges of wood
- ## remove old finish
orbital sander
- (palm sanders) orbit around 14000 rpm
- ## use standard sand paper
multi master
use triangular sanding pad
can reach into tight corners
sandpaper
three different grits are used when sanding woods
course: 30-50
medium grit : 60-100
fine grit: 120-180
Portable biscuit (plate) joiners
used when building cabinets shelving or furniture
biscuit adjustment size
the depth of the saw kerf is reduced for the smaller biscuits and increased for larger
double biscuit
can be created when working with wood that is at least 1” thick
should be at least 3/16 between material and biscuit
