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  • Saw Blade Selection

    I'm new to woodworking and so this is probably a basic question. I've decided to install hardwood floor in the upper floor of my home as well as on the stairs. So I decided to also install some wood panels and trim next to the stairs. I'm using 1/2" maple plywood for the panels and bought a plywood blade for cutting. However, I find that when I try to cut the trim (which is made of solid wood) with the same blade it has a tendency to burn the wood while cutting. I assume I would need a blade with fewer teeth but what would be a good blade to select for this purpose. I also want a good clean cut.

  • #2
    Re: Saw Blade Selection

    almost any 50 tooth combination blade should work. however, when i had burning, it was usually because either the rip fence wasn't parallel to the blade or the miter gauge wasn't perpendicular to the blade for 90deg. cuts. on miter or bevel cuts, burning can be caused either by misalignment somewhere or letting the workpiece shift during the cut.

    FTR, i use a lot of sheet goods (MDF, plywood, melamine) and i've never used a "plywood" blade with its many teeth and have almost never experienced chip out. i use a ZCI for the combo blade i am using and always make scoring cuts in the sheet goods prior to the actual cut.

    as far as burning on cross cuts, use a plastic drafting square to confirm that the miter gauge is perpendicular to the blade. also, make sure the blade is parallel to the miter slot in which the miter gauge is sliding. lastly, once the first two items have been addressed, clamp the workpiece to the miter gauge to confirm that it isn't shifting during the crosscut. attaching a piece of adhesive backed sandpaper to the miter gauge face will achieve the same result. good luck.
    there's a solution to every problem.....you just have to be willing to find it.

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    • #3
      Re: Saw Blade Selection

      One possibility is that the blade you used for cutting the flooring simply got dulled. Laminate flooring is very hard on saw blades and it really doesn't take a whole lot of cuts to dull a blade, especially if the blade wasn't engineered specifically for cutting laminates.
      Teach your kids about taxes..........eat 30 percent of their ice cream.

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      • #4
        Re: Saw Blade Selection

        You mentioned putting in a "hardwood" floor... was that solid hardwood, or was it an "Engineered" floor? The latter often contains other manmade or composite materials that could very well dull a blade quickly. If you put in a laminate floor, as BD referred, then that stuff just destroys blades and just about any other cutting bit (router, bandsaw blade, etc.). It's just brutally abrasive on blades.

        However, I've never had a lot of luck with so-called "plywood" blades. Perhaps they're great for subfloor thickness, wood paneling and the like, but I've found them too inclined to burning. But, that could very well just be me!

        I've used a variety of blades over the years and personally, I shy away from the "expensive" stuff. Just seems extravagent to put that much money into a blade, but of course there are those that swear by blades like the WoodWorker II. They may be right, but I have no experience at the price level.

        What have found to be a very good blade for my use is the Ridgid titanium-coated blades. I've used 40 and 50 tooth blades and have found the 50-tooth to satisfy both my crosscut and rip uses. I'm currently using them on my Craftsman radial arm saw (RAS), on my Ridgid miter saw (CMS), and on my Ryobi BT3100 table saw (TS). In all instances (except cutting "laminate" flooring) the blades have given me great cuts and have lasted a reasonably long time.

        While I mostly have been working in pine, I have cut a considerable amount of red oak when I trimmed out the kitchen, including wainscote.

        Much of the quality of a cut will of course depend on proper alignment of the tools used, including proper fence alignment. Feed speed can also make a dramatic difference and attention must be paid to the the cutting action of the blade. That is to say that the blade can't be pushed beyond it's ability to cut and expend the chips. That of course comes with experience and simply paying attention to the motor/blade sound and ease of feeding. If it sounds "strained" or feeling a bit mushy or sluggish, then you are overfeeding and bogging the blade down. Similarly, if you go too slow you may well get some uneven burn marks in your cuts.

        With proper feeding on my TS, my cuts are often "glueable" without further working. I've done some jointing of boards for larger width requirements and I've been very happy with my Ridgid 50-tooth 10" blade on my TS. Likewise, I've cut a number of "raised panels" and unless I hesitate in the middle of a cut, the exposed panel face will be nicely smooth and require little to no sanding. At the angle required to cut a raised panel in one-inch stock (20 degrees on my homemade jig) that's a little shy of 2-inches deep and the 50-tooth makes an acceptably smooth cut. (Realizing that "acceptable" is in the eyes of the beholder... but a quick pass with a hand sanding block takes away the rare tooth mark from an errant feed.)

        (I should mention that my BT3100 has an RPM of around 5,000 which I would suspect to make a better cut than a slower turning induction motor as found on heavier table saws. But still, the 50-tooth handles the rips quite nicely and without bogging down. Generally speaking it will do a 12 ft rip smoothly and easily with a fairly quick feed. I just listen to the motor and blade and the feel of the stock as I'm moving it into the blade. Harder woods like oak will require a slower feed rate than pine. But even with the latter, one needs to pay attention to resin and wetness... both of which I takes steps to avoid as much as possible.

        On my RAS, a slow feed makes for a nice smooth crosscut. Not as smooth as a with-grain rip of course, but smooth enough and without the usual bristle-like feel of a normal end grain cut. A faster pull through on the RAS will of make for a rougher cut of course. The same applies with using the CMS, where a nice, controlled downswing of the carriage will give you a much better cut than a "chop".

        Finally, it is very important to keep the blade clean and free of build-up on the teeth and in the gullets. That buildup can seriously bog down a blade, drag on your stock, and make feeding a lot more resistant than it should be. I make it a habit to wipe my blades down after several hours of use. Depends a lot on the wood, but a quick inspection after each use will tell you. Note that it's better to do it after use, rather than before as any resin buildup is easier to remove before it hardens.

        I hope this helps,

        CWS

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        • #5
          Re: Saw Blade Selection

          If you possibly can, bite the bullet now and buy one of the Forrest combo blades. This will prevent you from wasting a lot of bucks on cheaper blades as I did when I did not listen to woodworkers much more experienced and wiser than myself..............

          Big G

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          • #6
            Re: Saw Blade Selection

            Thanks for the replies everyone -especially CWS for the very detailed info. As I mentioned I'm fairly new to woodworking although I have done the odd thing or two in the past like refacing cabinet doors. CWS mentioned the cost of blades. I find the cost of wood tooling pleasantly cheap. I have done a lot of stone and masonry work and the tooling is so much more expensive. For example I recently purchased a speciality 14" masonry blade for use in my masonry wet saw for skimming some concrete blocks I cast with pretty aggregate (quartzite and sandstone) for use in the yard. The cost of the blade was $150 - just to contrast that to the blade prices I see for wood is easy on the wallet

            Anyway back to the topic - yes when I mentioned hardwood I was referring to solid wood - not engineered wood or laminate. The trim is also made of hardwood. Everything is maple (for best match I guess) although some of my stairs are curved so I will need to route the bullnose myself and I'm thinking of using a darker wood for this (or maybe even some stone like marble or travertine).

            I purchased the initial batch of trim but I'm considering buying the appropriate router bit and making the rest myself. I see that Freud makes the appropriate router bit for this. My plan is to also make the baseboard upstairs to a similar design to the wall panelling on the stairs.

            As far as the plywood blade - I don't think it has become dulled since I just used to today to rip two 4x8 sheets of plywood on the TS for the rest of the panelling. I guess it's just not possibly up to the job of cutting solid wood as I find I have to force the cut somewhat on the solid wood. That could be causing it to flex and burn the wood since I did notice especially on the miter cuts there is some deviation of the blade even though the piece was securely held in place.

            I will try cutting with a 50T blade and see how that works out.

            Comment


            • #7
              Re: Saw Blade Selection

              Forrest WW2 (expensive) or CMT (little less expensive) are both great great blades. I also like Systimatic, but they are out of business I heard. Don't rip with your plywood blade, it's murder on the blade and the wood. If you get a CMT or Forrest, your ply blade will probably not get used much anymore. As Finer9998 said, a scoring cut through the face veneer will give a perfect result using a combo blade. I don't even bother with the zero clearance insert and the cuts are perfect. Most 80 tooth ply blades aren't splinter free on crossgrain cuts, anyway. The exception I've experienced in the CMT melamine blade. That one is very, very impressive in melamine and crossgrain cuts in ply. Good if you're milling a lot of ply and don't want to score... which works great but it does slow things down considerably.

              If you still get burning or excessive saw marks with one of these combo blades, your saw fence to blade adjustment may need tweeking. I set the back of the blade 0.010 to 0.020 further from the fence than the front. This gives easy feed , super smooth cuts, no burns even on cherry and less danger of kickbacks (which will spoil your day). I use a machinist's starrett scale graduated in 0.010. Some guys like to use a dial indicator, that works even more accurately... just takes an extra couple of minutes. If you try this, *very important* you have to remember to re-align when you move the fence to the other side of the blade. You never ever, ever want to pinch the work as it leaves the blade. Burns and ruins the cut and huge risk of kickback.

              Good luck... be careful!

              Comment


              • #8
                Re: Saw Blade Selection

                What saw do you have?

                Tips for blade selection
                Last edited by hewood; 07-16-2011, 01:40 AM.

                Comment


                • #9
                  Re: Saw Blade Selection

                  Good tip from Andy about the fence. I do have a dial gauge somewhere in my toolbox but I'm not how you can use this for when the fence is far away (eg 2 feet). I suppose one can get a piece of steel bar stock to extend the reach of the gauge. I was trying to set the fence parallel to the blade - both at the front and at the back - but a good idea is to setup the way Andy mentioned.

                  The saws I'm using are - Table Saw - Craftsman model 315.284620, Circular Saw - Makita Magnesium Hypoid and for miter cuts HF 10" compound sliding miter saw. Also using a HF variable speed jigsaw for doing the cutouts for the stairs in the paneling - these are not accurate cuts as they will be hidden by the stair treads and risers.

                  Comment


                  • #10
                    Re: Saw Blade Selection

                    Originally posted by blue_can View Post
                    ...The saws I'm using are - Table Saw - Craftsman model 315.284620, Circular Saw - Makita Magnesium Hypoid and for miter cuts HF 10" compound sliding miter saw. ....
                    One important fact to remember about saw blades is that there's a balancing act of parameters, and for every benefit of a particular aspect there's also a downside. Unfortunately the manufacturers tend to promote the positives without mention of the downside. There's never a free lunch. Most of us are aware that more teeth equates to a cleaner cut, but more teeth is not always "better", as more teeth creates more heat, more resistance, more strain on the saw, and more burning. Fewer teeth tends to mean a faster more aggressive cut that's not as clean, but the parameters of the hook angle, top grind, and side clearance play a big role too, so the "truths" about saw blades are not absolutes...they're very dependent on each other. The trick is selecting the blade with the right balance for the right job.

                    A sliding compound miter saw (SCMS) and a RAS should use a blade with a low to negative hook angle to prevent self feeding...roughly in the range of -7° to +7°. A TS tends to better with a steeper hook angle to help keep the workpiece pinned to the table.

                    Here are some excerpts from the blog entry I linked above:
                    Teamwork: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.

                    Getting Technical: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.

                    Side Clearance: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.

                    Gullet: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: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.

                    Anti-vibration slots: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.

                    Tooth Grinds:
                    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 bevel can vary from about 10° to approximately 20°. The versatility of the ATB grind makes it a very common grind on many types of blades, especially woodworking blades. The 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. Essentially the steeper the bevel angle, the less tear out the teeth will cause, but also becomes increasing less efficient at ripping as the bevel increases. 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.

                    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. The sharp points of the higher bevels give up some durability and some ripping efficiency compared to some grinds, but are still capable of good ripping efficiency when combined with a lower tooth count and positive hook angle.

                    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. 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. 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.

                    Comment


                    • #11
                      Re: Saw Blade Selection

                      Yes thanks for the link on the blades - very useful reading. I definitely understand the concept of using different blades best suited to the job. I mentioned earlier that I do a lot of work with stone and masonry. I have at least 10 different blades and each one has a specific purpose - for example a blade for cutting marble is different to one for cutting granite. A granite blade will work on marble but there will be a lot of chipping. Masonry blades are again different and can be used to cut stone but with worse results.

                      With that in mind I did find the read on woodworking blades very useful.

                      Comment


                      • #12
                        Re: Saw Blade Selection

                        Hewood,

                        Thanks for the excellent post with its great information. Definitely a "saver" I think.

                        I agree with you about the "negative hook" angle on blades for use with the RAS and CMS. "Climb" is definitely a concern with these saws, although I think it is far more prevalent on the RAS as one pulls it into the stock and it will definitely want to self-feed and "climb" if you attempt to make this cut too fast.

                        I do find it a bit strange though that none of the saw manufacturer's (at least the one's that I have experience with) ever supply a negative-hook blade with them. That's not saying that I disagree with the recommendation for using a negative-hook blade on these, especially the RAS.

                        When I first started using the RAS (DeWalt) back in the 60's in high school, the "climb", self-feed was a factor to be taken seriously when learning to use this tool. I'm not sure if negative-hook blades were available back then, but they certainly weren't on that highschool shop RAS. But, the RAS was promoted to me, by my shop teacher, as a very "safe" saw when compared to the table saws of the time. I was definitely "shy" of the table saw as I had seen my father loose a three fingers to one when I was fourteen. The teacher had noted my "staying away" from these manglers and hearing my explanation had responded with his tutorage of the RAS.

                        I purchase my own Craftsman RAS in 1974 and again, it did not come with a negative-hook blade. Over the first decade or so I tackled a number or projects with just my RAS and convention saw blades. I'm a bit of a loner, so I had no one teach me otherwise. After more than 20 years of focusing on my career, my RAS pretty much sat idle, stored in the basement. It wasn't until my retirement in 2003 that I dug it out and renewed my interest in woodworking. It wasn't until then that I heard of the "negative-hook" angle blade recommendation for the RAS.

                        That of course only means that I've been "living in a cave" of sorts and certainly "not hearing" doesn't make sense of it one way or another. But still, I use a convention "positive-hook" angle blade on my RAS and as always, pay close attention and maintain a good control grip on my RAS when using it.

                        Thanks again for the excellent information,

                        CWS

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