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Material and Processes Technology Table Saw

Objective: The student will explain and demonstrate the proper and safe operation of the table saw. The student will pass both a written and practicum safety test with a score of 100%.

Introduction

After your wood has been jointed and planed to a working thickness, the next step would be to make the two edges parallel to each other. The tool used to perform this process is called the table saw. While the table saw can be used for a wide variety of cutting operations, the main two operations are:

• Ripping – cutting with the grain.

• Crosscutting – cutting across the grain.

Other cutting operations include:

• Chamfering – an angled cut (usually 45˚) between the face and edge or the face and end of a board.

• Beveling – an angled cut extending across entire edges or ends.

• Tapering – are angle cuts running along the entire length of the board (with the grain).

A typical table saw has several parts that you need to be familiar with. The saw arbor holds the circular saw blade. On the front and side of the table base are hand wheels used for raising or lowering the blade and for tilting the blade (which allows you to cut chamfer and bevels). The safety guard and splitter cover the blade and help to protect the operator. Tables are equipped with a t-slot for a miter gauge for crosscutting (cutting across the grain) and a rip fence for ripping (cutting with the grain). Table saws are sized by the largest blade diameter recommended for the machine. The saw in our lab is a 10 inch table saw.

Saw blades are made in many different sizes and styles. The difference in the blades lies in the size and number of teeth. Blades for crosscutting have many small teeth, which produces a smooth cut across the grain. Blades for ripping have fewer, larger teeth. The most useful blade for us is the combination blade, which is an all-purpose blade. A blade will last longer and cut better if the teeth are tipped in carbide. Carbide tip blades are more expensive, but are a better over value.

A dado head is a set of several blades. Dado heads are used to make cuts wider than those made by a single blade. Such cuts are necessary to make dado, grove, and rabbet joints. Dado blades can be one of two types. A stacked dado head consist of two outside blades, with different width chippers in the middle. The outside blades cut the edges while the chippers remove the stock in the middle of the cut. A second type of dado blade is called the adjustable or wobble blade. These are usually cheaper and produce a lower quality cut.

Ripping

Ripping is cutting along or with the grain of the wood. Before you can rip a board, you need to make sure the board has one jointed edge and that it has been planed flat and smooth. Adjust the blade to 1/8” above the stock’s surface.

Set the fence by lifting up on the fence locking handle. Set the fence to the desired distance by reading the ripping scale along the front edge of the saw. Push down on the locking handle to lock the fence in place. Never rip a board on the table saw unless you are using the fence. Failure to do so will result in kickback (when the stock is thrown back towards the operator with great force). The stock being ripped must be longer than the distance between the blade and the fence. Make sure that the guard and splitter are in place. The dust collect must be used when performing any cutting operation on the table saw.

Do not stand directly behind the blade when ripping. You should stand slightly to the left. This places you out of the line of fire in case of kickback. Place the straight edge of the board against the fence. Start the saw. Push the stock firmly into the blade with your right hand. Use your left hand to hold the stock against the fence. The rate of cut depends on the thickness and type of wood being cut. Feed the stock at a steady rate. If you feed the stock to slow, burn marks are produced on the cut edge. Always maintain a six inch margin of safety when using the table saw. If the board is less than six inches wide, use a push stick.

Crosscutting

Crosscutting is cutting across the grain. Crosscutting allows you to square the end of the board. To crosscut, you will use a miter gauge. The miter gauge rides in the milled t-slot on the surface of the saw table. Never crosscut a board on the table saw unless you are using the miter gauge. With the power to the saw off, set the miter gauge to 90˚ Use a plastic 45˚ triangle to check that the gauge and the blade are perpendicular to each other. Adjust the blade to 1/8” above the stock’s surface.

The stock must be jointed and ripped before you attempt to crosscut on the table saw. To cut only one or two pieces, slide the rip fence to the far right of the table. Mark the length of the board by making a thin pencil line on across the face and edge of the board using a try square. Draw an “X” on the waste side (the side you do not need) of the cut. Align the stock so it will be cut on the waste side marked with the “X”. Start the saw and stand to the left of the blade. Hold the stock firmly against the miter gauge with your left hand. With your right hand push the stock into the blade. Push the stock through the cut and pass the end of the blade. Turn the saw off and wait until the blade stops before trying to remove any of the waste pieces from around the blade.

To cut several pieces the same length, use a clearance block. Use a piece of ¾” thick stock clamped to the fence close to the front of the table. Set the desired length by adding ¾” to your needed length. If you need a piece 6” in length, you would set the ripping scale to 6-3/4”. Make sure that the guard and splitter are in place. Place the stock against the miter gauge with a squared end facing the fence. Slide the stock over until it butts the clearance block. Start the saw and holding the stock firmly against the miter gauge, make the cut. Once the stock has moved through the blade, slide the remaining stock along the fence of the miter gauge back to the left one or two inches. Repeat the operation for the desired number of pieces needed. Do not attempt to remove any of your cut pieces until you have turned off the saw and the blade has come to a complete stop.

Safety Rules

In order to use and operate the table saw safely, always use the following safety rules:

• Never place your hand in line with the cut.

• Always use the guards and other safety devices unless the operation requires the temporary removal of the guard. The instructor must be present for any operation that the guard is not used on.

• Never cut freehand on the table saw. Use the rip fence for ripping and the miter gauge for crosscutting.

• The saw blade should project no more than 1/8” above the stock being cut.

• Do not leave the saw until the blade has come to a complete stop.

• When you are done using the saw, lower the blade below the table surface.

• Never use the fence as a guide if the distance between the blade and the fence will be greater than the length of the stock against the fence.

• Never remove scrap cuttings from around the blade unless the machine has been turned off and has come to a complete stop.

• Stock must lie flat on the table. Never try to cut warped or twisted stock on a table saw.

• Edges placed against the rip fence must be straight.

• Never stand directly behind the blade.

• Always maintain a six inch margin of safety around the blade at all times.

• Use a push stick for stock that is less than six inches wide.

• Be sure that the stock has completely cleared the blade before removing it from the table.

• Keep the floor around the machine clean of scrape pieces of wood.

• Check the machine set-up careful before turning on the power.

• Never adjust the machine while it is running. Turn off the power and wait for the blade to come to a complete stop before making any adjustments.

• Do not reach over the saw blade or guard while it is running to secure pieces of stock.

• Never start the saw when the blade is in contact with the work piece or any other object.

Parts of the Table Saw

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Top

Blade Guard

Miter Gauge

guage

The two pictures show you the parts of the table saw that you will need to know. The lower figure has the blade guard removed. The student should use the guard at all times when cutting unless a special cut that requires the removal of the guard. In a situations such as this, the instructor must be present.

Extension Table

Fence

Throat Plate

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P

R

0

V

W

X

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Miter Gauge Slots

Tilt Hand Wheel

On/Off Switch

Blade

Tilt Angle Scale

Elevation Hand Wheel

On/Off Switch

Tilt Hand Wheel

Fence Ripping Scale

Fence Lock Handle

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