While it is best to consult with a blade manufacturer or supplier to determine the optimal blade for an application, some general guidelines are helpful.

Items like raisins, figs, and dried apricots are bursting with nutrition. Unfortunately, they’re also packed with a dense dose of sugar and non-soluble cellulose fiber, which can bind and trap those sugars around the tooth to the same extent as saltwater taffy. Your best bet? Sticking with the fresh version as much as possible.

Machine designed to use a serrated-tooth blade to cut metal or other material. Comes in a wide variety of styles but takes one of four basic forms: hacksaw (a simple, rugged machine that uses a reciprocating motion to part metal or other material); cold or circular saw (powers a circular blade that cuts structural materials); bandsaw (runs an endless band; the two basic types are cutoff and contour band machines, which cut intricate contours and shapes); and abrasive cutoff saw (similar in appearance to the cold saw, but uses an abrasive disc that rotates at high speeds rather than a blade with serrated teeth).

For example, too many teeth per inch can greatly reduce the cutting speed and ultimately make material impossible to cut. At a lower cutting speed, there is less penetration per tooth, causing more rubbing than cutting, which can result in substantial workhardening of material and strip the teeth. Workhardening also is compounded by an inability to evacuate chips because gullets load up more easily in fine-pitch blades, increasing friction.

Here’s another good reason to avoid refined carbohydrates, like white sandwich bread: The simple sugars quickly dissolve inside the mouth, causing a surge of acid that can erode tooth enamel. Plus, white bread takes on a gummy consistency when chewed, meaning small particles can get trapped between teeth.

Blade speed, which typically is measured in sfm, refers to the speed at which a blade travels around the guide wheel. Harder metals, such as steel, require a slower blade speed than softer materials, such as aluminum, to achieve a smooth cut.

“Typically, a variable rake is used for cutting at a slow rate,” Goldsmith said. “A ‘hard’ rake has a larger angle, allowing more room for chip formation. A ‘soft’ rake has a narrower angle with less room for chip formation.”

Managers at machine shops with saws closely monitor downtime associated with blade changes due to wear or breakage and spend a considerable amount of time and energy finding ways to increase efficiency.

Value that refers to how far the workpiece or cutter advances linearly in 1 minute, defined as: ipm = ipt 5 number of effective teeth 5 rpm. Also known as the table feed or machine feed.

Also known as down feed, feed pressure represents the amount of force that pushes a blade into material. Feed pressure can be static or adjustable, dependent on the machine being run, and is set by the saw operator.

For softer materials, such as carbon steel and aluminum, adjust the feed to 50% of the normal rate for the first 50 to 100 sq. in. Then, gradually increase the feed rate to 100%, he suggested.

3. Straight oils are not diluted or water-soluble. These are made with an oil base and sometimes contain fat and vegetable oils, as well as sulfur and chlorine. Oil-based products present the best lubrication but the worst cooling when compared with other fluids.

“When you first remove the pencil from the sharpener, it will take only the slightest amount of pressure to inadvertently break that point right off at the tip,” said Richard Klipp, president of Morgantown, Pennsylvania-based Behringer Saws Inc. “However, after a few minutes of writing, the point becomes less sharp and ultimately less susceptible to breakage.”

Users should consult a machine manufacturer for the best blade width, except for contour cutting in vertical machines when a chart can be referenced.  As for blade length, it varies according to the bandsaw machine type and specifications. The correct blade length should be shown in the bandsaw machine user manual.

So much for a refreshing glass of lemonade on the beach—the citric acid in lemons can wreak havoc on teeth. “Lemonade is a destructive combination of acid and sugar that leads to tooth decay and cavities,” Dr. Lepine says. “Even adding lemon slices to water can be a danger, because of the acidity it adds.”

The rake refers to the tooth shape, specifically the angle of the cutting end of the tooth. Most bandsaw blade teeth have a 0° rake or slight positive rake. The more positive the rake is, the more aggressive the blade cuts. A positive angle increases the tilt of the tooth face and is best suited for heavy-wall tubing and thick solids. Straight or less positive rakes are preferred for bundle and structural cutting. A variable rake indicates that teeth are set to different entry angles, resulting in different amounts of material removed by each tooth.

Already struggling with weak teeth? Skip crunchy fruits and veggies, which can further crack or damage fragile chompers. Apples and carrots are actually two of the biggest culprits of cracked teeth, Dr. Buzzatto notes. But don’t skip these healthy treats altogether: “Cut them into bite-size pieces before you enjoy them,” he recommends.

They might soothe your symptoms, but many cough drops have as much sugar as hard candy, experts warn. And because you suck on them for several minutes, and tend to pop them all day long when you have a cold, dental damage can be hefty. Skip the drops in favor of soothing your throat with herbal tea and water, or opt for sugar-free drops if necessary. (A tastier way to soothe a cough? Dark chocolate. Seriously, check it out.)

4. Semisynthetic fluids are a mix of synthetic and soluble fluids and share some of their characteristics. Semisynthetics are cheaper than synthetics. Insufficiently or overly diluted coolant can result in production of foam, inadequate chip removal or a lack of cooling during the cut.

Noshing a pb&j is reminiscent of childhood, but it’s a surefire way to prematurely age your teeth. The high sugar content of all three ingredients means that as soon as you bite in, enamel-eroding bacteria go on a feeding frenzy. And because peanut butter and jelly are both sticky, they allow the bacteria to adhere to your teeth.

Consider whether constant or variable pitch is better. With constant pitch, which is typically for general-purpose sawing, all teeth on a blade have uniform spacing, gullet depths and rake angles throughout the full length. Variable-pitch teeth have varying teeth sizes and gullet depths to substantially reduce noise levels and vibrations. The latter cuts all structurals, tubing and solids smoothly and quickly.

Machining operation in which a powered machine, usually equipped with a blade having milled or ground teeth, is used to part material (cutoff) or give it a new shape (contour bandsawing, band machining). Four basic types of sawing operations are: hacksawing (power or manual operation in which the blade moves back and forth through the work, cutting on one of the strokes); cold or circular sawing (a rotating, circular, toothed blade parts the material much as a workshop table saw or radial-arm saw cuts wood); bandsawing (a flexible, toothed blade rides on wheels under tension and is guided through the work); and abrasive sawing (abrasive points attached to a fiber or metal backing part stock, could be considered a grinding operation).

Once teeth are honed and broken in, a blade will cut faster and straighter and last longer than an incorrectly broken-in blade. Following a proper break-in process is a simple, easy way to ensure maximum productivity in a sawing operation.

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Savoring a sweet sucker might seem innocent enough, but not so fast. “Sucking these candies exposes your mouth to harsh sugars for longer periods of time,” Dr. Lepine says. “And chewing on them can break or crack teeth, fillings, and sealants.”

Using a high-quality metalcutting fluid is necessary to extend the life of a saw blade. Also, ensure that fluid is mixed in the ratio required for a job. This common sawing problem is avoided easily.

Sure, ice is sugar-free—but if you tend to chew on the cubes once you’ve finished a beverage, they can cause major damage. Dental experts say nibbling on ice is a major no-no as it can easily crack or break teeth.

Fact: Nobody looks forward to her biannual rendezvous at the dentist’s. But the discomfort from the poking and scraping of routine cleanings is nothing compared to the pain (not to mention the expense) of more intensive procedures, like fillings and root canals. So wouldn't it be nice to seriously lower your chances of needing dental work with some strategic eating?

“Some feel it is not worthwhile enough to slow down the cutting operation to break in a blade,” said Tim O’Loughlin, saws and hand tools product manager at The L.S. Starrett Co., Athol, Massachusetts. “However, while the break-in process does involve reducing the feed pressure for the first 25 to 100 sq. in. of cutting, the extra time is compensated many times over in the extended life span of the blade, in addition to the resulting improved surface finish in the cuts.”

Tangential velocity on the surface of the tool or workpiece at the cutting interface. The formula for cutting speed (sfm) is tool diameter 5 0.26 5 spindle speed (rpm). The formula for feed per tooth (fpt) is table feed (ipm)/number of flutes/spindle speed (rpm). The formula for spindle speed (rpm) is cutting speed (sfm) 5 3.82/tool diameter. The formula for table feed (ipm) is feed per tooth (ftp) 5 number of tool flutes 5 spindle speed (rpm).

Substances having metallic properties and being composed of two or more chemical elements of which at least one is a metal.

A constant-pitch blade can increase harmonic vibrations. This design may lead to excessive noise, undesirable saw or saw blade vibrations and, in severe cases, poor-quality cuts. When considering tooth pitch for blades, variable-pitch blades can vastly decrease harmonic vibrations. By varying tooth spacing, sawing rhythms are interrupted, chip evacuation improves and vibration abates, resulting in less noise and a better overall cut.

Machine that utilizes an endless band, normally with serrated teeth, for cutoff or contour sawing. See saw, sawing machine.

2. Synthetic fluids do not contain oil-based products and are made from compounds. Normally diluted when used, synthetics include additives that prevent corrosion. The fluids provide the best cooling when compared with other fluids but are expensive.

Convinced bottled water is better than tap? Not where your teeth are concerned. “The problem is during the purification process, water become more acidic," explains Brett Silverman, DDS, a Georgia-based dentist. "Acid and teeth equals cavities."

“Typically, blades need to be run with break-in in mind for two to three hours,” said Ebony Goldsmith, office manager and bandsaw specialist at Aldan, Pennsylvania-based Kaast Machine Tools Inc. “A blade that is not broken in will likely only last about an hour. A properly broke-in blade should last 100 to 150 hours.”

Your favorite sugary soda is a total smile saboteur. “Most contain an acid that can weaken tooth enamel—even diet soda,” explains John F. Buzzatto, DMD, MDS, president of the American Association of Orthodontists. If you must indulge, drink through a straw to limit soda’s contact with your teeth. (Though you may want to skip the soda altogether—and not just for your teeth. Check out 7 Side Effects Of Drinking Diet Soda.)

Angle of inclination between the face of the cutting tool and the workpiece. If the face of the tool lies in a plane through the axis of the workpiece, the tool is said to have a neutral, or zero, rake. If the inclination of the tool face makes the cutting edge more acute than when the rake angle is zero, the rake is positive. If the inclination of the tool face makes the cutting edge less acute or more blunt than when the rake angle is zero, the rake is negative.

Tendency of all metals to become harder when they are machined or subjected to other stresses and strains. This trait is particularly pronounced in soft, low-carbon steel or alloys containing nickel and manganese—nonmagnetic stainless steel, high-manganese steel and the superalloys Inconel and Monel.

Any machining process used to part metal or other material or give a workpiece a new configuration. Conventionally applies to machining operations in which a cutting tool mechanically removes material in the form of chips; applies to any process in which metal or material is removed to create new shapes. See metalforming.

Saws themselves shouldn’t need to be broken in, but blades do. Breaking in a bandsaw blade essentially means honing each tooth to form a microfine radius. This smoothing removes microscopic rough edges, which could rip off and cause tiny imperfections at the tip of each tooth as a result.

These images show a saw blade before and after the break-in process. The rough edges in the top image are realigned in the bottom image. Images courtesy of Kaast Machine Tools

Your favorite cinema snack is a double-pronged danger: Much like potato chips, popcorn can wedge between teeth and foster bacterial growth. Un-popped kernels are even worse. “When it gets to the bottom of the bag, people don’t realize that biting on kernels can break your teeth,” Dr. Dorfman says.

This process allows a blade to travel through the guides and become aligned correctly for cutting. Also, this increases the temperature of the blade, which permits imperfections in the material to bend instead of breaking blade teeth. The warming—followed by natural, inherent cooling—helps strengthen the blade substrate.

Tooth enamel is particularly vulnerable to dark colors, including red pasta sauce—porous enamel can easily absorb this coloring, leading to unsightly stains. Plus, the acidity from tomatoes makes teeth temporarily more porous. But instead of laying off the sauce, solve the problem by swishing with plenty of water while you’re enjoying an Italian repast.

Your teeth might feel cleaner after you pop a mint, but the real story: “Sucking on breath mints all day is like soaking your teeth in sugar,” warns Bill Dorfman, DDS, author of Billion Dollar Smile. Go sugar-free, and opt for mints sweetened with xylitol, which appears to combat bacteria associated with tooth decay.

Sorry chardonnay fans. While the deep color of red wine can cause discoloration, white wine might actually trigger even more damage. "The acidity in wine makes teeth more susceptible to stains, and white wine is generally more acidic," says Irwin Smigel, DDS, president of the American Society for Dental Aesthetics. "This acid can leave teeth vulnerable to stains from darkly colored food."

The sawing process has many variables, including the choice of blade for the job at hand, the selected feed rate and cutting speed, the rake angle and how a saw is broken in.

He said the same holds true for a saw blade. Right out of the box, a saw blade tip is very sharp and more susceptible to damage, such as a broken tooth, than after being used for a short period. Blade suppliers therefore often recommend running at a reduced down feed rate—usually 20% to 50% of the suggested rate—until tips are broken in. Afterward, the feed can be set at the recommended rate.

Blade pitch, defined as the number of teeth per inch, must be selected, O’Loughlin said. The number of teeth that contact a workpiece can affect blade performance and durability. Too many or too few teeth can cause strippage, especially when the feed rate or speed is too high or low.

Fluid that reduces temperature buildup at the tool/workpiece interface during machining. Normally takes the form of a liquid such as soluble or chemical mixtures (semisynthetic, synthetic) but can be pressurized air or other gas. Because of water’s ability to absorb great quantities of heat, it is widely used as a coolant and vehicle for various cutting compounds, with the water-to-compound ratio varying with the machining task. See cutting fluid; semisynthetic cutting fluid; soluble-oil cutting fluid; synthetic cutting fluid.

“There are plenty of foods that people should be avoiding if they want to keep their teeth in good shape,” says Guillaume Lepine, DDS, a Massachusetts-based dentist. We polled some of the top oral hygiene experts in the country to find out what’s not in their kitchen—and how they prevent food-related tooth damage whenever naughty nibbles do manage to make it past their lips.

Wide material requires a hard rake as the chips will be larger than those produced when sawing narrow material. The “set” refers to the pattern in which the teeth bend away from the centerline of the blade to create space for it to fit through the cut slot. In an alternate set, every other tooth is bent the same direction away from the centerline, and the other half of the teeth are bent the opposite direction away from the centerline. In a raker set, some teeth are not bent outward but left in the center to rake waste out of the cut. In general, raker sets are used with aggressive cutting blades.

That dentists avoid taffy and caramels like the plague isn’t exactly surprising. “Sticky candies get stuck between braces and teeth, allowing plaque to build up,” Dr. Lepine says. Plus, a chewy candy in the wrong place at the wrong time can easily take a tooth out. But here’s the good news: If you need a sugar hit, dark chocolate is soft on teeth and may combat plaque, according to recent research. (Get your tooth-friendly sugar fix with these 4 Guilt-Free Chocolate Desserts.)

Yesenia Duran is a Chicago-based freelance journalist who covers cutting tools and technology. She can be reached at sennyx@gmail.com.

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The service life of a bandsaw blade and the quality of the imparted surface finish are not determined solely by the product design from a blade manufacturer. Machine maintenance and operating practices can impact performance.

Feed rate is the speed at which material is removed by the teeth of a blade, usually listed as square ipm. The rate is determined by the material being cut, the blade used and the blade speed.

1. Soluble oil cutting fluids become an emulsion when mixed with water. These have effective heat transfer properties and offer good lubrication. They are popular because they are inexpensive.

A nutritious pick-me-up after your morning workout? Not quite. Sports drinks are packed with sugar and acids, Dr. Silverman says. And because we tend to swish sports drinks around in our mouths, the potential for cavities and erosion is even more significant.

Saw specialists agree that a broken-in blade should see significantly increased service life yet concede that users may have different perspectives.

From grapefruits to oranges, citrus boasts a bevy of nutrients. But they’re also packed with acids that can strip your teeth, says Dr. Lepine. Drink water when you enjoy a citrus snack, and swap in essential oils—which have less acidity—instead of the real thing when you flavor your water, he suggests.

Sadly, this summertime favorite is off-limits if you want your teeth to stay in one piece. Biting into corn that's on the cob can loosen or crack fillings and sealants, and damage orthodontic wires and brackets among patients with braces, Dr. Buzzatto says. And when it comes to dentures, chomping down on corn on the cob can easily dislodge the dentures. Instead of skipping corn altogether, though, simply scrape it off the cob before consuming.

Teeth on new bandsaw blades have very sharp edges, which easily can be chipped unevenly or destroyed if run at full speed with full feed pressure on the initial cuts and not broken in properly.  Image courtesy of L.S. Starrett

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They taste light as air, but the texture of potato chips (crunchy at first, then gummy post-chewing) means they tend to linger in your mouth. When chip particles get stuck between teeth, acid-producing bacteria indulge in a snacking attack that ups your risk of tooth decay. And since we tend to nosh on chips over a long period (hey, no one can eat just one), that means a non-stop period of acid production.

The process to break in a bandsaw blade varies depending on the characteristics of the workpiece material, said Jay Gordon, North American sales manager of saws and hand tools at L.S. Starrett. When breaking in a blade, users should run the machine at the normal blade speed.

For difficult-to-cut materials, such as nickel-base alloys, hardened steel, tool steel and stainless, adjust the feed rate to 75% of the normal cutting rate for the first 25 to 75 sq. in. Gradually increase the feed rate to reach 100% after 50 sq. in. As the feed increases to the 100% rate, be careful not to create unwanted vibrations by increasing the rate too quickly.