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A Guide to Circular Saw Blades

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A Guide to Circular Saw Blades

Postby Trevanion » 17 Jan 2021, 21:02

A common question that seems to appear very often on forums is "What sawblade should I get for my radial arm saw?" or "What's the best blade for my table saw?" and the answers never really change, so I thought I would compile this guide to help those asking the question.

I think for the hobbyist it can be quite daunting to select the correct blade for your machine and uses since there is such a massive variety of blades to be had and even more varying price differences. I hope I can break down all the jargon that all the manufacturers use and lay it out in simple terms to help you understand the differences between blades and what would be the best choice for you. If you're a newcomer to using a table saw I strongly recommend purchasing Steve Maskery's Workshop Essentials on the Table Saw which goes over all the health and safety aspects and how to use your machine properly, and above all else, make sure you do not annoy the push stick crusader.

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Selecting a Size

Blades come in a massive variety of sizes, but there are a few standard diameters that most machines are made to accommodate which are namely 200mm, 216mm, 250mm, and 300mm. You should already know what diameter of blade your machine takes but what is often overlooked is what the diameter of the shaft of the saw is so that you can select the correct bore blade for the saw. There are a few different sizes of bore but the main three are 5/8", 1", and 30mm, 30mm bore is the new standard on pretty much all machines of the last couple of decades and there is a far greater variety of blades available with this bore size.

If your machine has a smaller diameter shaft than 30mm, you can still use 30mm blades but you will need what is called a "Bore Bushing" or "Reducing Ring" or "Blade Washer" which will reduce the bore of your blade from 30mm down to the size needed for your saw. Something to keep in mind though is if your saw has "cupped flanges" the bore spacer can work loose out of the blade into the hollow spaces left between the flanges which will allow the blade to become unbalanced and an accident can occur. The best course of action is to superglue the reducer into the bore instead of peining or centre punching it into place as that can upset the tension of the saw plate and potentially warp the plate, It would also be good practice to use 30mm bore fibre washers either side of the blade that fit in the space in the flanges so that the reducer cannot work free. It is worth seeking out a lathe-turned bushing rather than one that's been punched out of a sheet like a washer, the turned bushing will be more accurate and concentric which will eliminate any wobble or vibration that you may get with a more inaccurate, stamped bushing.

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There are also different sized "Kerfs" (The width of material removed in a cut) ranging from just under 2mm up to 3mm, the narrower blades tend to require a new, narrower riving knife to be fitted so that the timber does not bind on it, it's best to stick to the kerf of blade your machine is designed for until you need a more specialized width of kerf.

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Something else to also keep in mind is whether your saw needs a blade with pinholes or not, some modern saws have pinned flanges to keep the blade, outer flange and nut/screw locked to the shaft without coming undone under braking. Good-quality saw blades usually come with pinholes pre-drilled into the saw plate so it's best to select a blade with them already put in if your saw requires it but it is possible to drill holes in an existing saw plate to make it work, a saw plate is fairly hard so you will want to use at least a cobalt drill bit or ideally a solid carbide drill bit a little larger than the pinhole diameter, clamp the saw plate solidly to a piece of timber and slowly drill the holes at the required spacing with plenty of oil/coolant, you really do not want to introduce heat or stresses into the saw plate which can mess with the tension of the blade and warp it .

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Cutting Tooth Materials

At the moment there are three different types of cutting teeth you will find on circular saw blades, one of them being obsolete and should be avoided. There is the very common and abundant Tungsten Carbide Tipped Blades (TCT), The eye-wateringly expensive Polycrystalline Diamond Tipped Blades (PCD) and the dangerous Plain Steel Blades.

TCT Blades have been the standard tooth tipping for a blade for decades now, almost every blade you can buy off the shelf these days is TCT tipped but not all blades are made equal. When looking for a TCT blade you should compare between blades how large the carbide pieces are, this will indicate how many sharpens you will be able to get out of a blade before it will need to be re-tipped or thrown out. TCT is an excellent material that lasts for a very long time, so the average hobbyist who is only working at weekends may not need to send blades off for re-sharpening often so long as clean, nail and debris free wood is used.

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Image courtesy of Scott and Sargeant

PCD blades are a fairly new innovation which claim up to 20x longer cutting life than their TCT counterparts. As with all new innovations they are exceedingly expensive and way out of the reach of most hobbists pocket-money I would think. Their main use is long periods of cutting in very abrasive materials such as MDF I do think in the next 20 years or so they will become the new standard when costs come down.

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Image courtesy of Scott and Sargeant

Plain steel blades are what gave the circular saw blade it's fearsome reputation, they were a primitive piece of equipment that could easily warp, bend teeth in the cut, crack down a gullet and all sorts of other nasty situations that could cause many problems from kickback to amputation depending on circumstances. I am a firm believer that leaps and bounds in the manufacturing of modern, stiffer saw plates and tipped blades have drastically reduced the number of accidents involving a saw blade compared to the bad old days. These are very outdated and should be avoided at all costs, although some do say that a very high-quality surface finish can be obtained from a well set up and very sharp steel blade and they are still quite commonly used on saws with diameters exceeding 16".

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Cutting Tooth Geometry

Having the correct cutting geometry on your teeth is what will make all the difference when you're selecting a blade for your particular machine. Known as rake or hook angle the teeth on a blade can be positioned so that they cleave material out very aggressively and quickly with a positive rake or they're positioned that they scrape the material and are more gentle for crosscutting applications with negative rake.

Positive rake blades are best suited to ripping tasks on a table saw and they tend to have a 20-degree positive angle to the teeth relative to the centre of rotation, they are aggressive in the cut and cut very efficiently when ripping because the teeth clear the material away rather than clog up.

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Neutral and Negative rake blades are best suited to crosscutting machines such as a mitre saw or radial arm saw because they won't have a tendency to "snatch" when you're cutting into the material as a positive rake blade will, they're not suited to ripping as they don't clear stringy material from the gullets very efficiently and cut very slowly.

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Types of cutting teeth pattern

The two main types of teeth you're likely to encounter when you're looking to buy a blade off the shelf are Alternating Top Bevel (ATB) or Triple Chip Grind (TCG), there are also a few different types of teeth but those two are the main ones you will find on most blades.

ATB Blades are the most common type and are used in most machines with good effect, they work in a way that scores each side of the cut which results in a very clean top surface cut. They work well in both crosscutting and ripping applications hence why they are the most common type.

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TCG Blades are second most common, they're designed to deal with more abrasive materials such as MDF and laminates as the tooth design is more durable and will hold up much longer in these materials.

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Hi-ATB blades are quite rare in the UK, They're designed for very fine crosscutting and panel cutting with very smooth cut surfaces. The sharpness of their points makes them very fragile though and prone to chipping.

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Flat Top Grind (FTG) blades are quite rare in the UK as well, as far as I'm aware you can't buy them off the shelf in sizes larger than around 6" in diameter and you'll have to ask a saw doctoring company to grind one to an FTG grind if you want one for doing joinery with the saw. Bear in mind, these blades are really only good for rip cuts as trying to crosscut with them is very similar to trying to cut down a tree with the flat face of a spade.

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Hollow Ground (HDF) blades are similar to a triple chip grind with the exception that the faces of the teeth are ground with a hollow rather than a flat cutting face, there are almost exclusively for cutting sheet material with veneers or coatings, due to the hollow grind on the face of the tooth it can produce exceptional cuts without chipping of the veneer or coating.

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Conical blades are exclusively for scoring blades in panel saws, you shouldn't need to worry about it unless you've got a panel saw with a scoring unit before the main blade.

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Some ripping blades will be what's called "Anti-Kickback", these kinds of blades have prodruding pieces of the plates before the cutting action of the tooth, the idea of this is that it limits how much material the tooth can remove in a single pass therefore lowering the risk of a kickback caused by overly-heavy feeding or a heavy bite which can throw a workpiece up and backwards towards the operator.

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The Amount of Teeth

The amount of teeth (as well as how sharp they are) also dictates how aggressive or smooth surfaced your cut is going to be along with the accompanying rake angle. Generalising, For ripping timber the average blade should have between 20-32 postive teeth for effective use, for both ripping and crosscutting in combination on a table saw and cutting panels to size a blade between 36-48 positive teeth should be used for effective used, for crosscutting exclusively in a mitre saw a blade should have between 56-96 either slightly positive (+5 Degrees) or negative rake teeth, for crosscutting exclusively in a radial arm saw a blade should have between 56-96 negative rake teeth to prevent the saw head from snatching the material and pulling itself through. There are exceptions but if you follow those guidelines you should be able to make a good choice.

The amount of teeth is also dictated by the size of workpieces you will be often working with, taking the mitre saw for example, if I were to be cutting mostly 4x4" tanalised posts where clean finish isn't really a problem I would look at selecting a blade with possibly fewer teeth than I mentioned above, but if I was working with smaller workpieces at around 1x1" in size I would definitely be looking at the higher tooth-count blades for smoothness of cut.

Too many teeth can pose a problem though, especially when ripping thicker pieces as with the amount of teeth in contact with the timber a lot of friction is generated which will at best burn the timber and at worst wreck the blade by warping it if excessive heat is generated, I've actually seen saw plates go blue in colour from the heat created by friction before.

Expansion Slots

I would say that expansion slots were one of the biggest safety improvements in circular saw technology, back in the bad old days this would've been a difficult process to achieve when manufacturing blades but as most companies laser-cut their plates out of a sheet it can be done the same time the plate is being cut out with no effort. The idea of the expansion slot is quite simple, when the blade is cutting a lot of heat is generated through friction and this is transferred into the saw plate which will expand with the heat build-up, on blades without the expansion slots if a lot a heat was generated the saw would warp drastically or in the worst case, crack down a tooth gullet from the heat expansion. The expansion slots are in essence "cracks" already put into the blade, so the blade can expand radially in their segments (typically four segments of the blade) without causing any issue to the blade. The slots also reduce the effect of warping on the blade when it does get very hot, it can still warp during cutting as I've experienced (I've seen the blade whipping from left to right by about 5mm before) but generally, once the blade cools down it will come back to perfect or only ever so slightly warped condition and may still be used for rougher work if slightly warped, whereas the older blades would either need to be thrown or serious saw-doctoring to bring back to life.

A typical expansion slot, shaped like a question mark:

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Noise-Reduction Slots

Noise reduction slots are cut into the plate of the saw about centrally between the teeth and the bore to reduce the harmonic resonance of the blade during cutting, this is less of an issue on machines with brushed motors such a mitre saw or site-style table saw as they tend to be louder than the blade spinning anyway but on machines with an induction motor such as a decent quality table saw or radial arm saw in can be a benefit to have a blade with noise reduction slots as this will cut down on the noise while the machine is running idly with nothing being cut. Some also claim that the slots cut down on vibration, resulting in a finer cut.

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Some noise reduction blades may have the grooves filled with resin, this drastically cuts down on the harmonics of a blade to the point if you tap the side of the blade with a metallic object you almost get a dull thud rather than a "gong" sound that you would normally get.


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Here's a video I made just to show the resonance difference between blades, the Freud has no noise reduction slots so it sounds like a classic gong, the standard CMT blade has noise reduction slots which help with the resonance, and the CMT Chrome has resin filled slots which as I said above, makes it sound more like a dull thud in comparison:




Trenching/Dado Cutting

Another question that frequently pops up is "Where can I buy a dado set", this is clear evidence that someone has been watching too many American youtube videos! :lol:

To get this out of the way early, it is NOT illegal to use a dado stack or adjustable groover in a table saw in the UK, this is false information that has circulated for many years. Due to changes in Woodworking regulations over the years, it has made it harder to use such equipment on saws in a commercial environment as saws now need to come to a 10-second stop time and be adequately guarded for the task. So long as your saw comes to a stop within 10-seconds with the cutter in place (and that it doesn't work loose from the inertia of stopping) and is sufficiently guarded with something like a SUVA guard a groover is perfectly legal to use in a commercial environment. However, this need not apply to the humble shed woodworker as the HSE isn't going to suddenly come banging on the door when you load the cutter into the machine, it's your home workshop and you can put yourself at any risk you want to, just don't moan about it in the A&E.

Since those regulations came into force, the sale of dado stacks in particular dwindled and there are only a couple of options available for a new set. However, while dado stacks are very versatile in the width of groove they can produce from 6mm all the way up to 30mm in some cases, they are considered quite outdated and clumsy to use compared to modern adjustable groovers.

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An adjustable groover is simply two pieces of overlapping steel with replaceable carbide inserts as the knickers and cutters. Some are adjusted by placing shims between the two plates and some can be adjusted with a screw dial. Generally, they don't have the range of size that a dado stack can do with the most common size starting at 8mm to 15mm although you can purchase ones that go from 4mm to 15mm which are made from three plates, then there are larger sizes such at 15mm to 28mm and so on. These adjustable groovers create a far cleaner cut than a dado stack and are cheaper to maintain in the long term as you get multiple turnings out of an insert which are relatively inexpensive whilst having a whole dado stack sharpened professionally isn't particularly cheap.

Another thing perhaps worth considering is the "wobble saw" or "drunken saw" which is a saw blade held captive in an adjustable holder that will hold the blade at an angle to the rotation which will create a groove once passed over with a piece of wood. They're fairly inexpensive as well as being easily adjustable without shimming. A negligible downside to these saws is since they're cutting by oscillating side to side it does create an ever so slightly curved bottom groove.

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Before looking too far at grooving tooling though, you need to ensure your saw can run the tooling with no issue as many saws made for the European market have short arbours that are only capable of running the single blade as intended although a few newer saws are being made now with long arbours. Some people get around this by having longer arbours made for their saws but you still need to ensure that your saw is powerful enough to run such tooling, I would say you need 3HP to comfortably use the tooling at their maximum settings.


American Blade Nonsense

With the sheer amount of American writings online, please do not fall for any American salesman nonsense you may see online such as "glue line rip" blades, these are only expensive versions of the TCG blades and offer no more "smooth" cut than a regular TCG blade. Another one which I think are a bit dubious are the "combination" blades that have four ATB teeth followed by a FTG tooth with a larger gullet, back in the bad old days of solid steel blades with set teeth I think this would've made sense as the tooth with the larger gullet would be left unset to remove the material from the centre of the cut whilst the four alternating teeth would leave a clean surface either side. I think it's a bit pointless with an unset carbide toothed blade where all the teeth are cutting in unison and looks to me to be more of a marketing gimmick than an actual reasonable feature. Stick to information from the United Kingdom and Europe and you should be OK.


Manufacturers

As I said earlier, not all blades are made equal and there are some manufacturers that stand head and shoulders above the rest, so I'll make a little list in descending order of the best you can buy in my opinion.

Atkinson Walker, I've recently learned that Atkinson Walker have started up again under "Sheffield Industrial Saws" and still make blades as excellent as ever. If you can stretch the budget you can't go wrong with one of their blades.

Swedex, A very expensive industrial blade manufacturer that are possibly making the best blades on the continent at the moment.

Leitz, a well-regarded German firm who makes top-notch tooling including saw blades.

Felder, Very good quality but very pricey for their SilentPower blades.

OMAS, An excellent Italian manufacturer.

CMT, another Italian blade manufacturer that produces very high-quality blades with large carbides without breaking the bank, they have a massive variety of blades too.

Freud, yet another Italian manufacturer, These are very good blades for the money and are recommended by most as they're so easy to find everywhere.

When looking at different blades as a novice, it's difficult to tell what makes a good quality blade and one that's not such good quality. As I mentioned previously, the size of the carbide dictates how much life you will get from your saw blade as a larger carbide will grant many resharpens of the teeth, in my photo below I have three of my 250mm blades, at the top I have a Metabo blade that was supplied with my mitre saw, in the middle I have a Freud crosscutting blade and at the bottom is a CMT fine crosscutting blade. From the photo, it's pretty obvious that the Metabo blade's carbides are much smaller than the other two blades and the CMT has marginally larger carbides than the Freud.

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There are probably some other brands worth looking at but these are the ones I can recommend myself, there are a lot of sub-par blades out there like the Trend blades which are expensive but no better than really cheap blades from elsewhere.

Care for Saw Blades

Whilst a fairly straightforward piece of equipment, a saw blade needs care and maintenance just the same as any other to keep it working in top form.

When a lower cut quality and burn marks appear, sometimes it is not the blade going dull but rather the build-up of resin on the teeth and body of the saw blade. Periodically, blades should be cleaned to remove this build-up, this can be done with special "blade cleaners" which some companies such as Trend offer, I have no experience of using them but I use methylated spirits as it is what I have on hand. I like to put the blade on a couple of paper towels and put it on an impermeable surface, which is usually my planer table and douse the blade both sides with the meths and leave it to sit for five minutes or so, I then come back with an old toothbrush and scrub off the resin. Sometimes it takes a couple applications of the meths to get rid of the resin completely but once it's removed you can remount the blade in the machine. I suggest running the blade into a non-critical piece of wood before doing any proper cutting first as the first cut will shed any meths and soft resin still on the blade onto the workpiece, if this was the problem with the blade the difference between the cut quality before and after cleaning will be night and day.

When the blade is genuinely dull, on an ATB blade it can be spotted by cutting into the timber and inspecting the cut, on a sharp blade the two points of the teeth that form a W will be a very sharp point shown on the timber, on a dull blade these will be rounded over, and obviously, with rounded points it isn't going to cut as efficiently or cleanly. Hopefully, in the photos below, you will see on some rubbish timber (I think it shows up better in lower quality timber) the cut quality with two identical 80 tooth cross-cutting blades, but one being very dull and one being brand new.

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A rough finish with the softer earlywood being torn out of the end grain, this would be an acceptable finish from a coarser blade with fewer teeth, but on an 80 tooth blade, this really struggled to cut through.

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A very smooth cut that feels glassy to the touch with almost no flaws to the surface excepting some cut marks which is to be expected, absolutely flew through the timber with no struggling from the machine whatsoever. Rough cut on the right for comparison.

Blades should be kept sharp and I suggest this isn't a task for at home, there are plenty of "DIY saw blade sharpening" videos on youtube (Mainly from America) going over many different methods of sharpening a saw blade such as mounting a diamond tile cutting blade in your table saw and touching the carbides to it to sharpen them up, or using a diamond hone of some kind. Whilst you could use these methods if you so wish, I much prefer to send off blades to have them professionally ground so that all the carbides are cutting in the exact same cut-circle and are actually ground sharp rather than sort-of sharp from a diamond file or similar. There are many companies in Britain that will do this for you and the going rate at the moment is around £5-10 a blade depending on the blade, any damage such as missing teeth, and the rates the company themselves charge, I will put a small list of companies that sharpen blades below, the only one I have experience with is Beverstock Saws, and it is always a good experience, the others I have heard good things about and have a good reputation.

Beverstock saws (Cwmbran) http://beverstocksaws.com/

NLS Tools (London) https://www.nlstools.co.uk/

Spindex Tools (Portsmouth) http://www.tewkesburysaw.co.uk/

Tewkesbury Saw (Tewkesbury, obviously) http://www.tewkesburysaw.co.uk/

Bennet Saw (Sheffield) https://www.ebsaws.com/

In a Nutshell

For effective dedicated ripping on a table saw you need a positive rake, low tooth count (20-32) blade ideally with anti-kickback nodules.

For effective combination ripping and crosscutting on a table saw you need a positive rake, medium tooth count (36-48) blade.

For effective dedicated crosscutting on a table saw, you need a very slightly positive (+5 degrees) or a negative rake, high tooth count (56-96) blade

For effective crosscutting on a mitre saw you need a you need a very slightly positive (+5 degrees) or a negative rake, high tooth count (56-96) blade.

For effective crosscutting on a radial arm saw you need a negative rake, medium to high tooth count (48-96) blade.

Trusted Suppliers

Here's a list of trusted suppliers of quality saw blades, if you've got any recommendations feel free to post them down below.

Scott and Sargeant: https://www.scosarg.com/

Cutting Solutions: http://www.cutting-solutions.co.uk/

Sheffield Industrial Saws / Atkinson Walker: https://www.sheffsaws.com/

Bennet Saw: https://www.ebsaws.com/

Swedex Saws UK: https://www.swedex.co.uk/

Leitz Tooling: https://www.leitz.org/en-gb/

Appleby Woodturnings: https://www.applebywoodturnings.co.uk/

If there's anything you think I've missed out please tell me and I can amend the post to add it :)

This thread used to reside elsewhere on the internet, it is now a Woodhaven2 exclusive which has now been expanded upon with updated images and knowledge.
Last edited by Trevanion on 09 May 2021, 10:59, edited 4 times in total.
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Re: A Guide to Circular Saw Blades

Postby AJB Temple » 17 Jan 2021, 21:53

Very glad to see you post this up again.

Thanks. It's excellent.
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Re: A Guide to Circular Saw Blades

Postby Nelsun » 18 Jan 2021, 01:19

Bookmarked to read again, and again and probably again as the need arises. From my initial Sunday night I-should-be-in-bed skim read I didn't see much on track saw blades... but I could have missed that. The dado / grooving section could go OCD and mention the Mafell and Festool track saws that take grooving cutting blocks - Whitehill have just started doing beading and v-groove blocks for the HK85 for example (https://www.whitehill-tools.com/cutter- ... -hk85-saw/).

Great post and much appreciated.
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Re: A Guide to Circular Saw Blades

Postby Trevanion » 18 Jan 2021, 08:34

Nelsun wrote: From my initial Sunday night I-should-be-in-bed skim read I didn't see much on track saw blades... but I could have missed that.


You're right, there isn't really anything on track saw blades in the thread but that's mostly down to my lack of experience with one as I've only done about five hundred cuts or so with mine on sheet material with the factory blade, it's not something I use often enough to be comfortable talking about it from an experience standpoint. I imagine most of the rules of thumb I've written still apply to a track saw though, lower tooth-count with positive rake blades for ripping down natural timber, higher tooth-count with positive rake for cutting up sheets and then more specialised blades for cutting harder materials such as melamine and aluminium.
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Re: A Guide to Circular Saw Blades

Postby novocaine » 18 Jan 2021, 09:14

to long, didn't read. which blade should I buy, I'm new to all this woodwork stuff and want to make a lounge chair like a Vitra Eames, I bought a lidl table saw but it doesn't cut straight and think it's the blade because everyone says that a good bandsaw blade makes a massive difference.

I now have a new "I'd rather_____ than______" I'd rather have tea with the push stick crusader than___________


excellent post Trevanion, that must have taken you ages to write.
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Re: A Guide to Circular Saw Blades

Postby Andyp » 18 Jan 2021, 09:46

My thoughts exactly. Not worth keeping most of the superfluous stuff so will delete .


Ps if the original article needs editing just let the MODs know.

mod Edit:

thread unlocked by request
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Re: A Guide to Circular Saw Blades

Postby Trevanion » 20 Jan 2021, 01:05

Post amended to add a section about blade pinholes which I stupidly neglected to mention and a section displaying different suppliers.

novocaine wrote:I'd rather have tea with the push stick crusader than___________


Just don't ask his opinion on one VS two push sticks... or push blocks!

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Re: A Guide to Circular Saw Blades

Postby JasonvG » 27 Jan 2021, 19:57

What a great guide, thanks for posting.
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Re: A Guide to Circular Saw Blades

Postby Trevanion » 09 May 2021, 11:01

So I've added some new content to the thread, there's now a couple of new sections on Expansion Slots, Noise Reduction Slots with an accompanying video to demonstrate the effectiveness, and I also expanded on the "Care of Saw Blades" section to include a couple of photos of a worn-out blade cut compared to a brand new blade cut.
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Re: A Guide to Circular Saw Blades

Postby Gremmy » 08 Jul 2021, 22:15

Evening all,

I’m after a reducing bush for a CMT 180mm grooving blade, going to try some finger joints for a jewellery box on the table saw for the first time (no I’ve not been watching loads of US youtubers, I don’t have a spindle moulder or decent router) I’m after a 35mm to 5/8th (15.88mm) bush and assumed they would be readily available off the shelf.. I’ve spent an hour trawling online and have come up with zilch.. I’ve always found 30mm to 5/8th no issues, but this is proving fruitless.
Trevanion, anyone you can recommend? Or is there a reason why this reduction isn’t available, perhaps something I’ve overlooked? If so, anyone up for turning me a bush for some lolly?
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Re: A Guide to Circular Saw Blades

Postby Trevanion » 08 Jul 2021, 22:23

Gremmy wrote:Trevanion, anyone you can recommend? Or is there a reason why this reduction isn’t available, perhaps something I’ve overlooked? If so, anyone up for turning me a bush for some lolly?


I had a quick search that also came up with nothing. I think I have a suitably sized piece of stainless steel kicking about so I could whip one out for you this weekend if you want, won't take too long to do.

Send me a PM if interested!
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Re: A Guide to Circular Saw Blades

Postby sunnybob » 09 Jul 2021, 05:34

A very specialised question for the guru 8-)

I've been asked to make some picture frames. What tooth arrangement would give me the best diagonal cut across soft wood?
I only have a mitre saw (NOT sliding) or table saw (contractor size), and I'm not going to make thousands, so I wont be spending hundreds and I'm looking for the best compromise please 8-)
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Re: A Guide to Circular Saw Blades

Postby 9fingers » 09 Jul 2021, 07:44

No doubt you already have decided but I’d go for around 4 teeth per inch of diameter, atb tooth profile. Negative rake for your mitre saw and positive rake for the table saw.
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Re: A Guide to Circular Saw Blades

Postby Trevanion » 09 Jul 2021, 07:46

sunnybob wrote:A very specialised question for the guru 8-)

I've been asked to make some picture frames. What tooth arrangement would give me the best diagonal cut across soft wood?
I only have a mitre saw (NOT sliding) or table saw (contractor size), and I'm not going to make thousands, so I wont be spending hundreds and I'm looking for the best compromise please 8-)


It depends on the size of your machine, but I get cuts that feel like glass on the end grain from my CMT 80T blade, this one specifically:

https://www.scosarg.com/cmt-285-saw-blade-chrome-d-250-d-30-z-80-b-3-2

It has a slight 5-degree positive cutting angle.

Getting absolutely spot-on mitres off a mitre saw, despite the name, is actually very difficult though but it can be done. I would be tempted to stick some self-adhesive 180 grit sandpaper to the bed and fence of the saw to help prevent the pieces from slipping slightly as you're cutting them otherwise you may end up with discrepancies in the cut which will make the mitres more difficult to glue up not and look very good once glued up.
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Re: A Guide to Circular Saw Blades

Postby sunnybob » 09 Jul 2021, 10:44

As I said, this is not going to be a big money earner for me, so I very much doubt I will buy a dedicated blade.
These are the 4 that I have;
Axcalibur 254 mm x 48T with 2.1 mm kerf
Freud 260 mm x 60T with 2.6 mm kerf
Dewalt 250 mm x 48T with 3 mm kerf
Unknown make possibly Ryobi 250 mm 24T with 3 mm kerf.
All positive rake.

Best of the bunch? 8-)
They are all in need of sharpening, but I dont want to be without all of them for a fortnight so will only have the recommended one done.
my wood projects are here https://pbase.com/sunnybob
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Re: A Guide to Circular Saw Blades

Postby Trevanion » 09 Jul 2021, 11:09

sunnybob wrote:As I said, this is not going to be a big money earner for me, so I very much doubt I will buy a dedicated blade.


Don’t look at it as just a dedicated blade for the job, I cut pretty much everything with my 80T blade from little trims to fence posts, materials including wood, plastic or even aluminium, I don’t use anything else in the mitre saw.

Depending on how sharp and what the tooth geometry is, I’d probably say your Freud would be the best.
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Re: A Guide to Circular Saw Blades

Postby sunnybob » 09 Jul 2021, 12:14

I tend to use whatever blade is in the machine at the time. I fit the thin kerf if I can get an extra slice out of a plank :lol:

I just cut aluminium fence panels last week with the freud, gave a nice finish.

Manufacturers choices are very limited here, usually American Milwaukie or Greek Kreator brands.

I have 2 separate people asking about picture frames, if I can get a commitment on at least a half dozen frames then I might buy a new blade for the job. If I only get a couple orders I'm working for a loss. :eusa-naughty:
Ta. 8-)
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Re: A Guide to Circular Saw Blades

Postby Gremmy » 21 Jul 2021, 20:48

Gremmy wrote:Evening all,

I’m after a reducing bush for a CMT 180mm grooving blade, going to try some finger joints for a jewellery box on the table saw for the first time (no I’ve not been watching loads of US youtubers, I don’t have a spindle moulder or decent router) I’m after a 35mm to 5/8th (15.88mm) bush and assumed they would be readily available off the shelf.. I’ve spent an hour trawling online and have come up with zilch.. I’ve always found 30mm to 5/8th no issues, but this is proving fruitless.
Trevanion, anyone you can recommend? Or is there a reason why this reduction isn’t available, perhaps something I’ve overlooked? If so, anyone up for turning me a bush for some lolly?


A big thanks to Trevanion for turning me, not one but TWO bushes for this oddball sized blade! I’d been away for a week and a bit so only just got to open the package :eusa-clap: :D
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Re: A Guide to Circular Saw Blades

Postby Trevanion » 21 Jul 2021, 21:16

Piece of kitchen roll included free of charge ;)
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Eureka, I found it.

Postby Vann » 02 Aug 2021, 10:14

Trevanion wrote:...This thread used to reside elsewhere on the internet, it is now a Woodhaven2 exclusive which has now been expanded upon with updated images and knowledge.


I want to get a rip blade for my tablesaw before I retire (about 3-4 months time) and went looking "elsewhere on the internet" as I'd bookmarked the thread. I was devastated to find just a dash "-" where once there was a detailed article.

So relieved to find it here. Now off to get an old, recently acquired, 40 tooth 18" blade retoothed (reteethed?), probably Flat Top Grind.

Cheers, Vann.
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