POWER SAWS

• Two main categories of power saws: Portable & Stationary.

• Work is fed into a stationary saw.

• Saws that are fed into the work are portable.

• Smaller tables saws that may be transported to the job site are still considered stationary because work is fed into it.

• Common portable saws are the Saber Saw & the Circular Saw.

Saber Saws• Used for straight or curved cuts.• Can cut internal or external radius

cuts• Most have a base that can be tilted to

make angled cuts.• Can accept a wide variety of blades to

cut various materials.• Blades may be fast-coarse cut or

smooth slow cut.• Can

Saber Saw Cont.

• Saber saws can perform an operation called a plunge cut.

• It has the ability to plunge into solid lumber to cut out interior dimensions.

• The following illustrations show this procedure.

Tilt base toStart cut.

Slowly engageBlade into workpiece

Continue cutFollowingLayout line.

Circular Saws• Used for rapid cross cutting or ripping

of large stock.• Available in a number of blade sizes

from 4 ½ to 12 inch diameter blades.• Newer saws are equipped with blade

brakes.• Can have a number of attachments

such as a rip fence which allows you to rip to width long stock.

• Many blade styles available for different work requirements.

Tips for Circular Saw Use

1. Make sure stock is supported and clamped securely.

2. Start saw with blade about ½ inch away from stock.

3. Follow your layout line making a straight cut: (binding the blade is caused by not following a straight line or sawing to fast)

4. Reduce forward speed at end of cut to reduce tear out or splintering.

5. When dealing with large stock such as plywood, have an assistant hold stock so as not to fall and bind the blade.

Stationary Saws

• Four basic types of stationary saws found in most wood shops.

1. Scroll Saw or jig saw

2. Band Saw

3. Radial Arm Saw

4. Table saw

                

       

 

          

 

                

Scroll Saw

• Used to cut curves in thin stock.• Are light duty machines which

perform same operations as the coping saw.

• Available in three basic designs.

1. Fixed or rigid arm

2. C-frame constant tension

3. Parallel arm constant tension• All cut with a reciprocating motion

(blade moves up and down)• All cut on the down stroke.• Maximum length of stock that can

be cut is equal to the distance from the blade to the back of the arm (throat).

Fixed Arm Scroll Saw

Cuts stock to about 1 inch thick.

C-Frame Parallel Frame

•Constant tension saws can cut stock up to two inches thick.•Blades tend to break less.•A variety of blades can be used including blades that cut 360 degrees.•Most blades are 5 inches long•Teeth of the blade must point towards the table when installed.•Pressure foot should always be placed snugly against the stock.•Do not let the blade rub against the foot.•Use relief cuts when possible to avoid binding the blade.

Bandsaws

• Used to make straight or curved cuts.• Can cut many types of materials.• Size of saw is determined by the

diameter of the wheels which is also the max size board which can be cut.

• 14 inch saws are a popular size.• Blade widths are available from 1/8

to 1 inch for a 14 inch saw.• Blades come in many styles and

tooth configurations depending on the material being cut and the finish desired.

• Do not cut a radius smaller than the blade size can handle.

Blade width selection for desired Radius to be cut

Table Saw

• Used for ripping, cross cutting, dado cuts, miter cuts, rabbets & bevels.

• Size is determined by the size of the blade which can be safely used on saw.

• Saws come equipped with blade guards and small fingers called anti-kickbacks which prevent wood from kicking back towards the operator.

• A Fence is used to accurately rip (cut with the grain) stock.

• A Miter Gauge is used to aid in crosscutting stock.

• Fence and Miter gauge should not be used at the same time without use of a clearance block.

                      

Fence

Miter gaugeBlade guard

Table

Blade HeightAdjustment WheelPower Switch

Blade AngleAdjustment Wheel

Saw Blades

• Many different types of blades can be used on a table saw.

• The most common are:1. Crosscut – teeth are similar to

handsaw crosscut teeth – used to cut across the grain.

2. Rip Blade – teeth are similar to hand ripsaw – used to cut with the grain.

3. Combination Blade – has both cross and rip teeth – used for all purpose work.

4. Some are Hollow ground with the blade thicker near the teeth allowing for clearance in the saw kerf.

Other Blade Types

• Special blades are available for cutting plywood, plastic & laminates.

• Carbide tipped blades are available for most cutting applications.– They cut cleaner and faster than

other blades.– They are harder and more wear

resistant than other blades.– Downside is that they cost much

more.– They require special sharpening

equipment when they become dull.

           

Rip

            

Plastic

           

GeneralPurpose

Dado

Power Miter Saws

• Also called chop saws.

• Used to cut accurate cross cuts or miter joints at any angle from 0 to 45 degrees.

• Three basic types:– Miter– Compound Miter– Compound Slide Miter

Blades are usually of the crosscut type since The cut is normally across the grain.

Cuts regular miters 0 to 45 degrees

Table swivels left to right to cut angles0 to 45 degrees. Head also tilts left to Right in order to cut compound angles.

Performs same operationAs compound miter withThe addition of aSlide that allowsLonger cutsOn widerBoards.

Slide Mechanism

Lock nut for adjustingTilt left to right.

Radial Arm Saw• Used for accurate cross cutting at

any angle.• Can be used for dado cuts, lap joints,

and molding cuts.• Compound miter cuts can also be

made.