There are a number of different factors that should be considered in saw blade selection. Decent quality is essential or you’re sunk from the beginning. The saw’s end performance is largely determined by proper setup and blade selection. You don’t need to spend big bucks to get a good blade, but more expensive blades typically increase your chances of getting good quality. As with many things, there are often a variety of choices that each have merit, so consider what’s best for your situation….a blade that’s perfect for someone else’s circumstances might not be right for you.
Blade selection is very much proprietary to your saw and what you cut. One of the early decisions should be to choose which types of blades are best for your situation. You can choose separate task specific blades that perform very well in a narrow operating range, or more of a “do-all” general purpose blade that will give “good” results in most applications but excel at none, or choose a variation that combines both philosophies. These all have merit depending on your situation, preference, budget, and cutting objectives. A decent purebred 60-80 tooth crosscut blade will certainly make “cleaner” crosscuts than a 30, 40 or 50 tooth general purpose blade of comparable quality. Inversely, a 24 tooth bulk ripper will certainly be more efficient at ripping thick material than the general purpose (GP) style blade, but it’s worth noting that there are downsides to using both of those blades. The key to “better” depends on how you define the term. Better performance in one aspect of cutting doesn’t necessarily mean it’s a better choice overall. Consider both sides of the equation before making a decision.
Task-specific or general purpose blades?:
Taking the approach of using task specific blades requires owning at least two blades that each excel in a limited operating region, and are typically unacceptable for tasks outside of their intended scope. They also require blade changes for each different task for optimum results. Two task-specific blades (typically a 24T ripper and a 60T or 80T crosscutter) will generally stay sharp longer than a single general purpose blade because they share the work load, but will cost more upfront and will also cost more to re-sharpen when the time comes. A general purpose blade will neither rip as efficiently as a true rip blade nor crosscut as cleanly as a dedicated crosscut blade, but you may find that it’s more than acceptable at doing both tasks for most situations. A valid argument in favor of using one high quality general purpose blade is that the GP blade leaves a cleaner edge than the rip blade, crosscuts faster than a crosscut blade, and does so with the convenience and cost of using one blade. Most higher quality general purpose blades will leave a glue ready edge, which is often as good as it needs to be. If you happen to do a lot of specialty cutting of fine veneered plywoods, veneers, melamine, MDF, plastics, etc., a blade made specifically for those materials is definitely recommended. If you tend to rip very thick dense materials regularly, then a dedicated bulk ripping blade is a wise choice for you right from the start. Sooner a later a decent general purpose blade will be useful, so it’s always a reasonable starting point IMO, even if you pursue separates later.
OK, so which general purpose/combo blade is better?
So you’ve decided to start with a single all purpose blade, but you discover that 40T ATB general purpose blades and 50T ATB/R combo blades both cover essentially the same cutting range. Which is better? Unfortunately, there’s not simple answer that’s absolutely true for all situations. Not only does it depend, but it’s somewhat subjective too. Each blade is unique, so there are many exceptions when trying to generalize. Overall I’ve noted that the premium 40T general purpose blades (Infinity Super General, Freud Fusion, Forrest WWII, Tenryu Gold Medal, Ridge Carbide TS2000, etc.) tend to leave a more polished edge, while the top 50T ATB/R combo blades (Freud LU83/84, Tenryu RS25550, Infinity Combomax, DeWalt/Delta 7640, Amana Tool 610504, Irwin Marples, CMT 215.050.10/216.050.10, DW7150PT, etc.) tend to leave slightly more pronounced swirl marks on the edges. So, while the premium 40T blades tend to have a performance advantage in cut quality due in part to their very tight side clearance, that same trait also tends to make them fussier about setup and technique, and can be slightly more prone to burning in some materials, while the 50T ATB/R blades tend to be easier to get good results with. If you’re meticulous about setting up your saw, the premium 40T blades could offer a slight advantage for you. If you’re less experienced with TS setup, or don’t like to tweak the saw much, the 50T ATB/R blades seem to be more forgiving.
The hybrid approach:
Breaking from convention, it’s also possible to choose separate blades that offer different regions of excellence than the conventional dedicated 24T bulk ripper and 80T fine crosscut blade. Even though the majority of general purpose/combination blades have 40T or 50T, there are some blades with 30T and 60T that can each be used in a somewhat limited general purpose capacity. Though typically considered a “rip blade” and a “crosscut blade” respectively, each offers more versatility than a traditional 24T and 80T task specific blade, while still offering excellence in a specific cutting task, though to a somewhat lesser degree. They create an “either/or” scenario, and can reduce blade changes while offering superior performance compared to a 40T or 50T blade. A 30T blade with an ATB grind and a steep positive hook angle (like the Forrest 30T WWII, DeWalt DW7653, & Tenryu IW-25530D1) will rip more efficiently than comparably designed 40T general purpose blades in thicker materials (up to ~ 3” given ample power), will make cleaner rips than a standard 24T ripper…it may even crosscut acceptably well in some situations (it’s subjective). The weakness of the 30T blade is that it’ll have more tearout for fine crosscut or fine plywood type duties, but it will give “glue line” rips and more versatility than a standard 24T ripper, which potentially means fewer blade changes and acceptable performance in a wider region. A good blade of this type will be suitable for wide range of tasks that don’t require ultra fine finish cuts….the finer the finish requirement, the less desirable this blade becomes. Inversely, a good quality 60T ATB or Hi-ATB blade with a positive hook angle (like the Forrest WWI, Infinity 010-060, or Freud LU88) will make cleaner rips in the range of ~ 1” to 1-1/4” (depending on the material, saw, etc.), and will make cleaner crosscuts and ply cuts than a conventional 40T ATB general purpose or 50T ATB/R combo blade, so is a good choice where cleaner cuts and lower ripping efficiency are suitable. The weakness of the 60T blade will be loss of efficiency in thicker ripping, having more tendency for bogging of the saw and burning in thicker materials. The combination of the 30T and 60T blades teamed together offers increased range over a standard 40T or 50T GP blade, better versatility than standard 24T and 80T separates individually, and longer edge life between sharpenings than a single blade. Depending on your situation, a good 30T or 60T blade may be suitable as the only blade you’ll need, but the two blades combined as a set will “tag-team” to cover a very wide range of tasks extremely well. The best part is that either can still be left on the saw with less urgency for blade changes for most tasks….sort of a “best of both worlds” scenario if you’re willing to pop for two blades.
Tastes Great, Less Filling!
You’ll also be faced with a decision of kerf width. Most standard 10” blades fall into two kerf classifications – full kerf or thin kerf, but there are exceptions, and the classifications are ill-defined. There’s no set standard to what constitutes full or thin kerf blade, but I’ll offer a general rule of thumb. Most full kerf blades hover near 1/8” (0.125”, ranging from roughly 0.118” to 0.145”), while most thin kerf blades are about 3/32” (0.094”, ranging from roughly 0.090” to 0.105”). There are also some “mid kerf” blades that fall in between, in the 0.110” range. There are also ultra thin kerfs in the 0.055” to 0.08” kerf range available from some manufacturers for special applications. Many smaller diameter blades are “UTKs”. Which kerf width to choose can be as easy as following manufacturer’s recommendations of using thin kerf blades for saws under 3hp (ie: most benchtop, jobsite, contractor, or hybrid saws fall in the 1hp to 2hp range), and full kerf blades for saws with motors 3hp and up (ie: industrial cabinet saws), but that’s where the simplicity ends and the debates begin. There are pros and cons to each, and there are legitimate arguments for both kerf widths. As with many choices, it’ll boil down to a matter of preference and your particular situation, but I’ll try to explain the logic of both philosophies. To some folks, it’s just a matter of the math being simpler with a 1/8” blade than a 3/32” blade. It can also be a matter of not knowing any better, or what was available on sale at the time of purchase (BTDT!). Both kerf widths will work with most saws, but note that changing kerf width can skew the zero reference on the measuring tape on a left tilt saw, so you’ll need to address that if you change widths.
Even though the width differences appear very small, a full kerf blade is typically 33% thicker than it’s TK counterpart. A wider kerf blade makes a wider cut, thus taking more wood and requiring more power to make the cut at the same speed…a similar principle to a lawn mower’s width of cut. There will also be a proportionately higher amount of sawdust with a full kerf blade, more wood consumed in the process, and even somewhat higher noise levels. Wood savings can be a consideration, though a minor one for most hobbyists. That consideration may become more significant if you handle a lot of expensive wood. You’re likely to encounter situations where a full kerf blade will bog a smaller saw more easily than a TK would, most notably in thicker materials. The wider the kerf, the more power required to pass the blade through the material. Slowing down the feed rate can help compensate somewhat for the additional power requirements, but slower cutting means more of a tendency to burn the wood, and less ability to cut efficiently in thick materials.
Full kerf blades tend to be more stable than their TK counterparts due to the increased steel thickness and body mass, but require more power to spin. The heavier mass of a full kerf plate will handle the stresses of heat better than a TK blade, so is often a more suitable choice for high volume applications. If you’re using a saw that’s under 3hp, a TK blade will pose less resistance to your saw. A high quality thin kerf blade with proper tensioning of the body during manufacturing will rival the cut quality and performance of a high quality full kerf blade, and can be a very suitable choice for a home shop, smaller saws, and even in many commercial settings where wood consumption is a concern. Which width to choose depends a lot of your saw and the material being cut. Your splitter or riving knife width should also be part of the consideration. Choosing a blade that’s thinner than the splitter blade can cause the board to stop mid cut if the board binds on the splitter. There are legitimate arguments for both kerf widths, and the choice will come down to your personal preference and circumstances.
Many blade manufacturers recommend the use of blade stabilizers, dampeners, or stiffeners with their blades. Especially with thin kerf blades, but many make the same recommendation for full kerf blades too. From a technical perspective, it’s more right than wrong to make that recommendation. Not much harm in the recommendation, and there’s some possible benefit for both buyer and seller, so why not? First off, be aware that you give up some cutting height capacity with a disk installed. The larger the diameter of the stiffener, the less height capacity that’s available. Secondly, my experience has been that there’s not much noticeable difference with or without them when using good blades on a well tuned saw. A high quality modern blade mounted on a properly running table saw while cutting flat straight stock shouldn’t need stabilizers. I’ve read far more responses on internet forums that agreed with my view than opposed it, but as always, there are some exceptions and differing views. I vote to save your money and take someone special to lunch with the money saved. If your saw or blade has a runout/vibration problem, in some situations a stabilizer can help, but note that it’s usually a $20 band-aid for a deeper problem, and not a cure. Better to find the root cause and correct that instead of installing a stabilizer/stiffener.
What’s In A Name?
To further complicate blade selection, it’s not as simple as just buying a reputable brand name blade either. Many brands have multiple lines aimed at different market niches that are each made to different price points and different objectives. So, always buy the blade, not the brand!. Brands like Infinity, Forrest, and Ridge Carbide only offer a single line of premium blades with a variety of models for different applications within that line. Companies like Freud, CMT, Amana, Tenryu, Leitz, Delta, DeWalt, Bosch, Irwin, and Systimatic offer multiple lines often with different intended applications. Some of those blades are premium quality that will rival the performance of Forrest, Infinity, and Ridge Carbide, but some will not so you can’t just select a brand and be confident you’ve got a blade that’s representative of their best blade(s) for fine woodworking uses. While not all are at the “premium” level, you’ll be hard pressed to find a clunker from companies like Freud, CMT, Amana, Systimatic, or Tenryu….just be certain that you’ve chosen a blade that’s appropriate for an intended application and you’re likely to have very good success with it. Companies like DeWalt, Oldham, Bosch, Irwin, and Delta have some great blades too, but they also have some mediocre blades at the entry level that I prefer to avoid. Don’t dismiss the excellent blades because of the lesser blades of the same name. Learn as much as you can about a blade’s tooth configuration and geometry, and know what series or line the model comes from. Trying to decipher the hierarchy within a brand can be a challenge, but some of the basic clues are things like the price, fit & finish, carbide thickness, packaging, features, and even the labels and descriptors the manufacturer uses can help. Terms such as Premium, Professional, Woodworker, or Industrial tend to indicate higher quality levels than those labeled Construction, Contractor, Value, Bulk Pack, or Economy, though be on the look out for companies who use the premium terms strictly as a sales gimmick without backing the title with improved quality. Look to see if the plate has fine laser cut expansion slots versus those that are from a cheap stamped steel plate. Large shiny carbide is certainly no guarantee of quality either, but it does indicate that they’re not trying to take the cheapest route. Sloppy brazing doesn’t necessarily impact cut quality, but it can suggest that some corners were cut. Country of origin can also be an indicator but it’s far from a guarantee of quality…however, if a company produces top notch blades made in the USA, Germany, Japan, Israel, England, Canada, the European Union, or Italy, the odds are good that their Chinese imports are not their best line. There are some really good Chinese-made blades, but most brands move manufacturing to China to cut costs, not to improve quality. Also consider the retail circumstances. In general, woodworking specialty stores tend to carry higher end lines than most homecenters, but there are always exceptions.
So how do you know a good blade from a bad blade without trying them? You don’t really, but there are some visual clues to help….compare the pics below and note the contrasts between the first two pics and the last two pics….look at the carbide size, brazing, fit and finish, expansion slots, etc. The better blades tend to have much larger and more highly polished carbide, as well as neater brazing, and computer controlled laser expansion slots (top 2 pics), vs the tiny carbide and sloppy brazing of a cheaper blade with a stamped expansion slot (bottom 2 pics). None of these factors ensures better cut quality, but it’s a strong indicator that care was taken when the blade was designed and manufactured. Which would you rather own?
It’s important to acknowledge that a saw blade is only one component of a more complex cutting system and sequence of events that occurs during cutting. The blade is only one possible variable if cutting results aren’t up to expectations. Proper blade-to-fence alignment is one of the most important steps in setting up your saw. Also, your table saw needs a good throat insert to perform well. A great blade will cut poorly if the throat insert is flexing or isn’t flush and level with the top causing the wood to catch. A zero clearance insert will help improve cut quality…make sure it’s stiff, flat, and flush. The table needs to be reasonably flat too but it typically takes a large deviation to noticeably affect the cut, and is a difficult problem to resolve if one exists. A splitter or riving knife is a recommended safety device…be sure they’re aligned with the blade too. While you’re looking your saw over, check your arbor and arbor flange for runout. If the arbor wobbles even a little, the saw can vibrate excessively and the blade won’t cut well. Pulleys and belts can impact the arbor’s ability to run true so check them too. An improperly tuned saw won’t run well, and will mask the performance of a good blade. (Makes you wonder how many times a premium blade was deemed no better than a modest blade because the saw wasn’t capable of revealing the differences of the better blade…). Most saws spin in a self-tightening rotational direction. The arbor nut only needs to be snug to start. If you over tighten it, you risk bending the blade and diminishing its potential cut performance. To give the blade and the saw a fighting chance at perfection, the material being cut should be flat and straight. A flat straight work piece stands a much greater chance of being cut smoothly and accurately than a work piece that’s rocking, twisting, and/or pulling away from the blade. And finally, if you can’t remember the last time you cleaned your current blade, go take it off the saw, spray it with household degreaser (409, Greased Lightning, Fantastic, Goo Gone, Simple Green, etc.), and hit it with a toothbrush or brass bristle brush to clean it up! (5 minutes from start to finish). If it’s really grungy, and you happen to have some kerosene on hand, give it a good overnight soak. A dirty blade cuts like a dull blade, creates excess heat, leaves burn marks, and eventually causes it to become a dull blade prematurely. Clean your blade(s) often and they’ll perform like new for a much longer time.
Tooth count is one of the more important considerations of a saw blade. Number of teeth should be based on the intended application along with the other design parameters of the blade. If all other parameters are equal, more teeth will equate to a cleaner cut, but it’s not as simple as that. There are several other factors that influence cutting performance in addition to tooth count, and more teeth is not always better. More teeth also means more resistance to the saw, slower feed rates, more friction & heat, and a higher chance of burning. Fewer teeth equates to a faster more efficient cut, but typically also means a rougher cut. Depending on thickness, it’s recommended to have 5 to 7 teeth in the material for crosscutting and finish cuts in hard wood, and 3 to 5 teeth for ripping operations. Depending on blade diameter, it’s common to see between 10 and 30 teeth on a specialized ripping blade, and 60 to 100 teeth for crosscut blades and blades used for plywood, veneers, melamine. laminates, and other sheet goods. Note that more teeth cost more to make, more to buy, and more to sharpen when the time comes, but more teeth also tend to hold an edge longer because they share the work load.
The side clearance is another important feature that is essentially the amount of overhang a tooth has relative to the blade’s body. The tangential and radial side clearance angles are the geometry of the sides of the teeth. These features all combine to determine how much “polish” or “burnishing” characteristics the teeth will contribute to the edge of the wood. Tight side clearances and tight angles mean that more tooth makes contact with the edge of the cut, and thus gives a more polished look. The same characteristic can also increase burning if the feed rate slows too much, and/or if the wood is naturally more prone to burning.
A gullet is the trough between the teeth. A larger gullet allows for more efficient chip removal, which is one of the reasons that a blade with fewer teeth will cut faster…there’s simply more gullet space on a lower tooth count blade. Ripping operations have larger chip size than crosscutting operations, which makes lower tooth count blades more conducive to ripping operations. Crosscutting operations tend to have smaller chip sizes, so a dedicated crosscut blade can have more teeth around the perimeter of the blade, which allows for a cleaner cut.
Hook angle (or rake) is the amount of forward or backward lean of the teeth on a blade. The hook angle can range from roughly -7° to as much as + 22°. The steeper the hook angle, the more aggressive and faster the feed rate will be. A steep, or positive hook angle, will have more pull on the material than a low or negative hook blade, which is a feature well suited for ripping operations on a table saw. A low to negative hook blade is well suited for use on a sliding compound miter saw (SCMS) or radial arm saw (RAS) to prevent “climb” or self feeding of the material, and is highly recommended when cutting metals on any type of saw. The steeper hook angles will feed faster but can also increase tear out characteristics at the exit of the cut. A lower hook angle will have less tear out, but will require more feed pressure and may have a higher tendency for burning to occur if the saw bogs down.
Laser cut anti-vibration slots help channel heat buildup during the cutting process, allowing the blade to expand and contract without distorting and destroying the tension of blade’s body. Ultimately, they help the blade run true with low noise and vibration for a cleaner cut. Filling the slots with silicone can further reduce noise. Some blades will have copper silencers in the “keyhole” of the slot.
ATB – Alternate Top Bevel (ATB) is a very versatile grind that features a bevel across the top of the tooth that angles from the outside in, alternating between left side and right side. The angle of the top bevel can vary from about 10° to approximately 20°. The steeper the top bevel angle, the less tear out the teeth will cause, but also becomes increasing less efficient at ripping as the bevel increases.The versatility of the ATB grind makes it a very common grind on many types of blades, especially woodworking blades. The top bevel helps reduce tear out on cross grain and plywood cuts, is reasonably durable, and can still be fairly efficient at ripping with the grain. The ATB grind is very well suited in a configuration as a higher tooth count dedicated crosscut blade, and as a versatile medium tooth count general purpose blade. Note that the top beveled teeth produce a slight “V” in the kerf of the cut, so will not leave a truly flat bottom in groove cuts.
Hi-ATB – Teeth with a top bevel of roughly 25° or higher are commonly referred to as High Alternate Top Bevel grinds. Hi-ATB grinds are a variation of the ATB grind, and have the lowest tear out characteristics of any other grind. They’re extremely well suited for ultra clean cuts in plywood, laminates, melamine, veneers, and ultra fine crosscuts in hardwood, so are most commonly found in high tooth count blades intended for those purposes, but are also starting to show up in some general purpose designs. The sharp points of the higher bevels give up some durability and some ripping efficiency compared to some grinds, but can still give good edge for low volumes (like those of a hobbyist) .
ATB/R – The ATB/R grind is a combination of two different tooth grinds in one blade. It typically features groupings of five teeth that consist of four ATB ground teeth and one flat top “raker” tooth with large gullets between the groupings. Note that the ATB ground teeth protrude slightly above the flat raker tooth, so this configuration does not leave a perfectly flat bottom….it tends to leave slight grooves along the edge of the cut similar to most stacked dado sets (a trait often called “bat ears”). Common configurations are found in a 10” blade with 50 teeth and a moderately steep hook angle of 10° to 15°. The ATB/R combination grind is well suited for both ripping and crosscuts, and general purpose woodworking applications on a table saw or compound miter saw, but use a variation with a milder hook angle suggested for SCMS and RAS.
FTG – Flat top teeth are used on blades intended primarily for ripping wood with the grain. A flat top grind (FTG) is very efficient at removing large chips from the kerf, and is a very durable grind that tends to have very good edge life. A flat top grind is the only grind that will leave a truly flat bottom kerf, which also makes it a good choice for cutting grooves and splines. The FTG is commonly found on ripping blades with a steep positive hook angle and lower tooth count, typically 10 to 30 teeth, but can also be found as part of a combination grind in a variety of hook angles intended for other applications.
TCG – The triple chip grind (TCG) also combines two different tooth grinds in one blade – a flat top grind and a trapezoidal grind, which is essentially a flat top tooth with chamfered top. The TCG alternates between a flat top “raker” and a trapezoidal tooth which protrudes slightly higher than the raker tooth, which inherently leaves a slight groove in the middle of the kerf. The TCG is extremely durable, and exhibits low chip out characteristics in brittle materials, which makes it well suited for cutting metals, laminate flooring, very hard woods, abrasive materials like MDF and teak, and sheet goods like melamine. Its durability also lends itself to high volume applications where edge life is important.
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