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Saw - Basic Cuts
Introduction Right
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Sawing--crosscutting (cutting perpendicular to or “across” the wood grain), ripping (cutting parallel to or “with” the grain), making miter joints and other joinery cuts--is the most common, most necessary woodworking operation. You'll spend most of your operating time on the Mark V sawing. There are six basic saw cuts: crosscut, rip, miter, cross bevel, rip bevel, and compound miter (Figure 2-1). All other cuts, no matter how intricate, are combinations of these basic cuts. It is essential, therefore, to master the basic cuts in order to use the table saw to its fullest capabilities. In this tip, we concern ourselves primarily with crosscutting and ripping. It is interesting to note that perhaps ninety percent of all operations on the table saw are ripping and crosscutting. It should also be noted that the table saw should not be used in through--sawing operations without the saw guard in place. Warning: Always use saw guards and safety devices as recommended.
Use the accessories shown in Figure 2-2 for sawing operations. To set up your Mark V in the table saw mode, follow the instructions in the Owners Manual that came with your machine. As you work in the sawing mode, you'll find that the Mark V is an extremely capable table saw with several special features:
There are several types of saw blades available for the table saw. Each of them are ground and/or set to accomplish specific wood-working operations. The following are the most common blades and what they do: All-Purpose Blade--This blade (Figure 2-3) is the sawing work-horse of most woodworking shops. The deep gullets between the teeth provide plenty of room for waste removal on ripping operations and the sharp tooth points do a reasonably good job when crosscutting. An all-purpose blade enables you to start with basic operations like crosscutting, ripping, and mitering, but it is not the only blade you can use. You'll get better results on particular types of sawing when you use a blade that was specially designed for the work you are doing.
Crosscut Blade--A crosscut blade has many small teeth ground with alternating top bevels, sharp points and shallow gullets (Figure 2-4). The teeth cut cleanly across wood fibers, and since the waste that is produced is a fine sawdust, the blade functions efficiently with shallow gullets. However, small teeth and shallow gullets can cause the blade to “choke” if you try to force the cut. Here, even more than with other blade designs, feed pressure should be slow and steady--only enough so the teeth will cut as they were designed to cut. The crosscut blade does a respectable job on miter cuts, may be used on plywood, but should never be used for ripping.
Ripping Blade--A ripping blade (Figure 2-5) has large teeth ground with a square chisel tooth, large gullets and is designed for sawing with the grain of the wood. There is considerable support metal to back up the cutting edges, and generous gullets catch and disperse the sawdust. Because it has a special design, the ripping blade should never be used for general sawing.
Hollow-Ground Blade--A hollow-ground blade (Figure 2-6), or “planer blade” as it is sometimes called, produces a cut nearly as smooth as a planed edge. Most blades have set teeth; that is, alternate teeth are bent a bit in opposite directions This forms a kert that is wider than the blade thickness so the blade has clearance in the cut. The hollow-ground blade is reduced in thickness from the points of its teeth to the full-gauge center area that is indicated by the arrow in the photograph. Since this design, rather than set teeth, gives it clearance in the cut, it produces smoother cuts than other blades. The blade can function without binding or burning itself or the wood by using it with the correct projection. In a strict sense, it is a combination blade, but it is not one to leave on the machine for general sizing cuts. It does fine on plywood, but may not be tempered to stay sharp for an extended period of time under the abrasive action of the plywood glue. Additional uses for the hollow-ground blade include smooth crosscuts or miter cuts, trimming moldings, and other advanced cutting techniques.
Plywood Blade--A plywood blade has many small teeth and very little set (Figure 2-7). This blade trims and cuts plywood and other laminates. Because of the very small teeth, it produces a smooth cut and also reduces splintering along the kerf. The plywood blade can also be used for crosscutting soft woods, preferably finish cuts only. General use will dull the teeth quickly, as will certain types of plywood cores (particle and fibre). For cutting particle or fibre core plywood and other sheet stock, it would be better to use a carbide-tipped blade.
Carbide-Tipped Blade--Carbide-tipped blades (Figure 2-8) are more expensive than conventional blades; but, since they stay sharp for much longer periods of time, they can prove to be more economical in the long run. They are high-quality saw blades specially designed for splinter-free results in hardwoods, softwoods, and materials like hardboard and plywood, whether you are cross-cutting, ripping, or mitering. Carbide is a tough material, but it is also brittle. Be careful when handling such blades; store them so they can't contact another blade or object. Never use a car-bide blade to saw second-hand lumber that could contain nails. Cutting Tips--With any table saw blade, remember that the teeth above the table's surface rotate in the direction of the operator and enter the top surface of the workpiece first; therefore, place the wood with the finished side upward. This applies to plain plywood, veneers, and any form of plywood with laminates attached. When both sides of the wood are finished, use a fine-tooth blade with minimum set or a hollow-ground blade. Also keep in mind that the kerf is the slot formed by the blade. Its width will differ depending on the style, the gauge, and the amount of set on the teeth of the blade. The kerf should always be on the waste side of the cutline. Saw Blade
Maintenance Sharp blades are, of course, a must. They cut more efficiently and are safer to use since the operator doesn't have to utilize excessive force to feed the stock-a situation that could cause hands to slip. Some woodworkers sharpen their own blades, but it isn't recommended. A less than perfect job will do more harm than good and can even ruin the blade. The cost of sharpening is small, and the professional's experience and special equipment will ensure that the blade will be returned in like-new condition.
Storing Blades A blade storage case like the one shown in Figure 2-9 will hold six blades and, when fitted with a handle, will serve as a tote for a full assortment of blades. Layers of 1/4" plywood (Figure 2-10), some solid and some with a semi-circular cutout, are laminated to make up the storage area.
You can provide for more blades by adding more plywood layers, but you must adjust the dimensions of the hinged cover if you do. To hold the blades steady and keep them from moving about, cement a piece of thick foam rubber to the underside of the cover's top piece.
There are times when you can substitute a special insert for standard equipment. The purpose of a special insert is to minimize the clearance around a cutting tool. A special insert is necessary, for example, when cutting pieces of wood so thin that the saw blade pulls them down beneath the table.
Special inserts, like those shown in Figure 2-11, are easily made from 1/4" hardboard by using a standard insert as a pattern for shape and hole location. Once the special insert is made, raise the table to its highest position and install the insert (Figure 2-12). To cut the slot in the insert, turn on the machine, set the speed dial to the proper speed, and very slowly lower the table over the blade (Figure 2-13). Each time you use the insert you must align the slot exactly with the blade. Warning: Before using the table saw, read and understand these important safety instructions: Danger Zone--The danger zone on the Mark V in the sawing mode extends 3" on all sides of the blade, 2' in back of the blade, and 8' in front of the blade. The reason for the extended danger zone in front of the blade is that a saw blade can kick a board back. The blade may also kick a board forward, but not as hard as backward. Safety Rules for Table Saws--Here are some safety rules for operating the table saw:
Saw Guards--The Mark V is equipped with saw guards to provide a physical barrier between you and the moving blade, no matter what height or angle you adjust the worktable. These saw guards have several other safety features. The lower saw guard has a dust chute that allows you to attach a dust collection system so you can collect the waste while you're sawing. The upper saw guard is clear so you can see the cutline. There's a removable plastic insert in front of the blade to catch wood pitch. This can be easily cleaned to keep your line of sight clear. The upper saw guard on the Model 500 is mounted on a splitter that keeps the saw kerf from closing and binding the blade. On this splitter there are two anti-kickback pawls that help keep the blade from kicking the stock back toward you. The upper saw guard on the Model 510 has a riving knife that is positioned 1/8" from the blade regardless of stock thickness. The riving knife has anti-kickback cams that help capture the stock in the event of a kickback. Avoiding Kickback--If, for any reason, the saw blade should bind in the workpiece, it can kick the stock back toward the operator with great force and speed. Also, if any piece of scrap (or other object) is left on the table and slides into the moving blade, it can be thrown with considerable force. Actually, kickback is one of the greatest hazards in running a table saw. Some of the common causes of kickback include:
Blade projection (Figure 2-14) refers to the amount of blade that is visible above the workpiece. Except in the case of hollow-ground blades, which are set slightly higher, keep the projection within 1/4"and 3/8". The upper guard has a depth-of-cut scale so it is easy to adjust the projection of the blade. Just lower the guard over the blade and then adjust the table height. For example, if you are sawing 3/4" stock and want a 1/4" projection, adjust the table height until the tip of the blade aligns with the 1" mark on the guard.
Another way to set blade projection is to use a step gauge like the one shown in Figure 2-15. A gauge you can make by laminating 1/8" pieces of hardboard is shown in Figure 2-16. Both the scale on the saw guard and a height gauge can be used to set the projection of saw blades and other cutters like the dado accessory.
Before you begin any table saw operation, set the Mark V to run at the correct speed. To do this: turn the machine on, turn the speed dial to the correct speed and let the saw come up to speed. Caution: Never turn the speed dial when the Mark V is stopped. You could damage the speed changing mechanism. Always turn the speed to “Slow” before turning off the machine. The correct speed is determined by the operation you're about to perform and the type of material you're sawing. Generally, you can use faster speeds in softer woods. Faster speeds will also give you a smoother cut. Slower speeds give the machine more torque to get through hard, dense woods. To determine the right speed for the job, refer to Table 2-1. A good rule of thumb is: The deeper the cut or the harder the wood, the slower the speed. But if the blade turns too slowly, you may get a rough, splintery cut. Crosscutting, cutting a board perpendicular to or across the grain, is one of the most common wood-working operations. It's also known as a “cutoff” operation, or cutting a board to length. Basic Crosscutting
Techniques Adjust the table height so that the saw blade will protrude about 1/4" above the stock. When the table height is properly adjusted, make a five-point check. All five locks--power plant, carriage, table height, table tilt, and quill--should be secure. Check that the miter gauge is square to the blade, and adjust the safety grip to the thickness of the stock. Warning: Always use the miter gauge to guide the stock as you saw it. Decide on which side--right or left--of the blade is the most comfortable for you to stand when you saw. Warning: Do not stand directly in line with the blade. Place the miter gauge in the slot on the same side of the blade that you're standing.
Mark the stock where you want to cut it, using a square and a sharp pencil (Figure 2-17). Remember that the saw usually makes a 1/8" kerf as it cuts. If you cut straight down in the middle of your line, your stock will be 1/16" short. Instead, cut on the outside of the line. Squeeze the safety grip to clamp the stock in the miter gauge. Push the stock forward until it touches the saw teeth so that you can see if the cutline is properly aligned with the blade.
Pull the stock away from the blade. Turn on the Mark V, turn the speed dial to the proper speed, and let the machine come up to speed. Then carefully guide the stock past the blade. Use your free hand to help support the stock and keep it flat against the face of the miter gauge (Figure 2-18). When crosscutting narrow stock or cutting off a thin piece, use a special insert (Figure 2-11) or move the blade close to the table saw insert on the side of the blade where the stock is being cut. This will help keep small pieces of stock from falling through the insert. Don't feed the stock any faster than the blade will cut. If the machine bogs down, slow your feed rate and let the saw get back up to running speed. Warning: Never use your free hand to push against the free end of the stock. This binds the blade and can result in a dangerous kickback. Use your free hand for additional support only. After the cut is complete, turn the speed dial to “Slow” and turn off the machine. Warning: Never pick up a cutoff while the blade is still running. Your hand holding the miter gauge could slip Into the blade; your free hand might nudge the cutoff into the blade, causing a kickback; or the action of the blade on the cutoff might pull your free hand into the blade. It takes only a few seconds for the blade to stop after the switch has been turned off. Crosscutting
Long Boards If possible, don't start by cutting. little pieces off the end of the long board. This is hard to do accurately. Instead, start cutting long boards in the middle. This gets them down to a manageable length quickly.
Use an extension table mounted in either the power mount or the base mount-whichever end of the board needs the most support. If you crosscut a lot of long boards, you will want to invest in a second extension table so that you can support the stock at both ends. The Model 510 has the extension table system that provides additional support for cross-cutting operations (Figure 2-19). A miter gauge extension will also provide extra work support because it increases the surface area of the miter gauge. Actually, it's good practice to use an extension on all crosscut work, especially if the workpiece is long.
The extension that is available for the Mark V, shown mounted in Figure 2-20, comes with attachment hardware and is easily mounted because of the pair of slots that are part of the miter gauge design. The position of the extension can be reversed so it can be placed in the miter gauge for use on either side of the saw blade. It's a good idea to have several extensions on hand, each one for a specific purpose. Should you wish to make your own, the standard extension can be used as a pattern or use the dimensions and hole locations in Figure 2-21.
Figure 2-22 shows an adjustable miter gauge extension that is ideal for crosscutting and mitering. Use a router to form the 1/4" slot that positions the extension on the miter gauge. In the same way, form a 5/8" wide counterbored slot centered on the 1/4" slot to accept the two carriage bolt heads. Glue fine sandpaper to the face, as mentioned later, for more holding power.
Miter gauge extensions do not have to be a specific length. When crosscutting extra-long pieces, the extension can span across the table and beyond it (Figure 2-23). When necessary, the extension can rest on the extension table. When you use a long extension, the saw blade will cut through it. This will not harm the extension, and the kerf that is formed can be used as a guide. The cut line can be marked on the stock with a square and then aligned with the kerf in the extension. Thus you know beforehand the line that the saw blade will follow. When you mark the stock, be sure to place the head of the square against the edge that will bear against the extension. Check the miter gauge adjustment if the kerf doesn't follow the line. You can use the miter gauge safety grip with an extension. Many woodworkers face extensions with fine sandpaper to provide a high-friction surface that is an aid on all operations, but especially useful when the miter gauge is adjusted for an angular cut. The sandpaper helps to keep the workpiece from moving or drifting when cutting miters. The sandpaper may be applied to the extension with rubber cement. Crosscutting
to Length
Except for squaring off the end of a board, crosscutting is usually done to cut a piece, or several pieces, to an exact length. When you need only one piece, the simplest method is to cut to a line that you have marked with a square. You can visually align the mark on the workpiece with the saw blade or YOU can use a miter gauge extension that has a kerf through it (Figure 2-24). Other methods should be used when you need more than one piece of the same length. One method is to work with the miter gauge stop rod (Figure 2-25). By adjusting the two rods, any number of pieces can be cut to any length up to 18". The stop rod can be used at either side of the miter gauge, which allows it to be used whether the miter gauge is on the left or right side of the blade. For short pieces, up to 8" long, secure the short rod in the miter gauge and use the long rod as an adjustable stop. For longer workpieces, up to 18", secure the long rod in the miter gauge and use the short rod as an adjustable stop.
Adjust the stop rod for the length you require (Figure 2-26) by measuring between the end of the rod and the blade. If the blade has set teeth, be sure to measure from the tip of a tooth that points toward the rod. Once the setting is made, any number of pieces can be sawn to the same length by butting the end of the workpiece against the stop rod and making the pass. Warning: Do not position the miter gauge stop rod so that it crosses in front of the blade.
A miter gauge extension that you make yourself can be used for cutting duplicate pieces (Figure 2-27). The extension, which can be used whether the miter gauge is on the left or right side of the saw blade, will allow cutting of duplicate pieces as long as 24". To use it, measure between the sliding stop and the saw blade and then do the sawing.
Construction details of the extension are shown in Figure 2-28. When you make the stop, allow just a fraction of clearance so it can slide smoothly in the extension's T-shaped slot. Accessories you make, like this one, should be carefully made, smoothly sanded, and given one or two applications of a penetrating sealer. When you treat them right, they become tools that will function for as long as you do woodworking.
Spacers for the Rip Fence--The rip fence can assist in cutting-to-length operations if a spacer is clamped or screwed to the rip fence (Figure 2-29). The spacer must be at least 1-1/2" thick. Figure 2-30 shows how a screw-type spacer is made. Warning: The rip fence alone must never be used as a stop to gauge the length of a cutoff. The cutoff, when the pass is complete, will bind between the fence and the blade and be kicked back.
The distance between the fence and the blade minus the thickness of the spacer determines the length of the cutoff. The workpiece is butted against the spacer and then advanced for cutting. When the pass is completed, there is ample room between the rip fence and the blade so the workpiece can't be trapped. Another spacer design is shown in Figure 2-31. An advantage of this one, made as shown in Figure 2-32, is that it can be placed anywhere on the rip fence, which makes it usable for other wood-working operations. Warning: The workpiece MUST clear the spacer well before the end of the cut to avoid binding the work-piece between the spacer and the blade.
Crosscutting
Wide Stock
Crosscutting wide boards requires maximum support in front of the blade. On the Model 500, actual table length in front of the blade with projection set to cut 3/4" stock is about 7", which is good support for average work. On the Model 510 there is 10" of table in front of the blade. A front table extension (Figure 2-33) is available as an accessory for the Model 500. This increases the usable table depth in front of the saw blade by 7". A single locking knob makes it easy to attach or remove; its miter gauge slot is compatible with the slots in the worktable. Crosscutting
Extra-Thick Stock
When you are cutting unusually thick material and the machine's maximum depth of cut won't allow you to cut through in a single pass, you can do the job by making two passes. Warning: When cutting part way through stock, it is necessary to remove the upper saw guard. Whenever the upper guard is removed, keep the lower guard in place and work with extreme caution. Set the blade's projection to a little more than half the stock's thickness and make one pass. Use a square so you can pencil mark the line of the kerf down one side of the stock. Invert the stock and place it so the pencil mark is in line with the saw blade and make a second pass (Figure 2-34).
Ripping is cutting parallel to or with the grain of the wood. It's also known as cutting to width. General Ripping
When ripping, use the rip fence to help guide the wood. Mount the rip fence to the table, slide the rip fence so that it's the desired distance away from the saw blade, then lock it in place. Use the quill feed to make fine adjustments (Figure 2-35). Be sure to measure from the fence to the tip of a tooth that's set toward the fence. When properly aligned, the rip fence automatically sets itself parallel to the saw blade. However, on critical setups, it's wise to check this. Measure the distance from the rip fence to the saw blade at both the front and back of the machine. Mount a feather board in front of the blade to help hold the stock against the fence.
Stand in front of the Mark V, on the opposite side of the blade than the rip fence. (This position will help you keep the stock pressed against the fence as you rip it.) Turn on the Mark V, turn the speed dial to the proper speed, and let the saw come up to speed. Place the stock on the table and against the rip fence. Slowly feed the stock into the blade while keeping it pressed firmly against the rip fence (Figure 2-36). Don't force the cut or go any faster than the blade can cut. Warning: As you finish the cut, use a push stick or push block to help feed the last portion of the stock past the blade (Figure 2-37). This will keep your hands and fingers out of danger. When the cut is complete, turn off the machine and let it come to a complete stop before removingthe stock or any scraps.
Ripping Narrow
Stock When ripping narrow stock--1-1/2" to 3" wide--use the fence straddler to finish the cut (Figure 2-38). When ripping stock less than higher than the thickness of the stock (Figure 2-39) and screw it to the rip fence so that the fence doesn't interfere with the saw guard or the stock being cut. Use a similar size piece of scrap stock to push the good stock past the blade (Figure 2-40). Caution: Do not use the plastic push stick from the safety kit. When the good stock is clear of the blade, turn off the Mark V. Hold the scrap push stick steady until the blade comes to a complete stop, then move it away from the blade. To keep small pieces of stock from falling through the table insert, move the blade close to the insert on the side of the blade where the stock is being cut, or use a special table insert. The construction details for the special table inserts are shown in Figure 2-11.
Ripping Wide Stock If you're ripping stock that is 5-1/2" to 8-1/2" wide (Model 500) and 8-3/4" to 10-3/4" wide (Model 510), you can mount the rip fence so it straddles the extension table and the worktable. Be sure that the extension table and the worktable and rip fence are properly aligned, then slide the power plant and carriage to the right so that the worktable butts against the extension table. Position the rip fence so the saw blade is the desired distance from the rip fence and make fine adjustments with the quill feed. As you feed the stock, the rip fence will accurately guide the stock (Figure 2-41). Ripping Large
Stock
Whenever you need to rip large pieces of stock such as plywood, paneling and other sheet materials it is very important that the stock be properly supported throughout the cut. Also, get a helper if the material you're ripping is too large to safely handle by yourself. There are several setups that provide the proper support. One setup for ripping sheet materials is to mount an extension table on one or both sides of the machine, then mount the rip fence on the extension table.
You can also mount a support table (Figure 2-42) or use a roller stand at the outfeed end of the worktable. For even more support, also use a support table (Model 510 only) or roller stand at the infeed end of the worktable. With the Model 510, you can also use the extension table system (Figure 2-43). Ripping Long
Stock
One way to support the stock is to mount a support table to the outfeed end of the worktable (Figure 2-44) or position a roller stand 1' to 4' away from the outfeed end of the worktable (Figure 2-45). You may also want to position a roller stand at the infeed end of the worktable. If the stock is extremely long (over 6'), you will want to use a roller stand positioned 2' to 4' beyond the support table (Figure 2-46). On the Model 510 you can mount a second support table at the infeed end of the worktable for extra support.
As you feed the stock, it comes off the outfeed end of the table and the support table and/or the roller stand will support it.
Figure 2-47 shows a rip fence extension that is used for ripping long and wide boards, and even plywood. To make the rip fence extension (Figure 2-48), use 3/4" plywood or clear straight hardwood. Drill and counterbore holes for the mounting bolts. Attach the support to the back with glue and screws. Mount 1-3/4" wide strips to the bottom edge for more support.
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