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By Trevanion
#1316010
A common question that seems to appear very often on the forum 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.

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. 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.

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.

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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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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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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.

Cutting teeth 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, they are aggressive in the cut and cut very efficiently when ripping because the teeth clear the material away rather than clog up.

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.

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.

ATB 4+1 blades are usually for a combination rip/crosscutting blade, four regular ATB teeth followed by a flat tooth "raker" to remove the rest of the material, these blades are ideal for a table saw if you're doing a mixture of both ripping and crosscutting and you don't want to change blades constantly.

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.

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 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.

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 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.

Trenching (Dado cutting if you're American)

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: The first consideration to be made should be "can my saw take a dado set?" as most modern European saws have arbours that are too short to accept any more than a single blade, there are ways around this with a bit of engineering but that's out of the realms of most people. If your saw fortunately does have an arbour long enough such as many of the older English saws like the Wadkins you can buy new dado sets from CMT for about £150 but in my opinion, these types of tooling are a bit outdated and clumsy to use. Whilst dado sets are perfectly usable and pretty versatile, If I were to be considering buying a set for my saw I would be looking to buy an "Adjustable groover" rather than a dado set, these are just two pieces of metal which can be shimmed to whatever size you want very quickly and they cut much cleaner and more efficiently.

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They work very well, but the downsides that they're not as massively adjustable as a dado set which can go from 6mm or so up to 20mm and they're a little more expensive than a dado set.

Another thing perhaps worth considering is the "wobble saw" which is a regular 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.

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American blade nonsense

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 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, These guys have gone bust so you won't be able to buy a new blade, but if you get a chance to pick up a second-hand or new-old stock blade do it as they were the best available.
  • Swedex, A very expensive industrial blade manufacturer who are possibly making the best blades at the moment.
  • Felder, ££££££££££££££££££££££££££££
  • CMT, an Italian blade manufacturer that produces very high quality blades with large carbides without breaking the bank, they have a massive variety of blades too.
  • OMAS, another excellent Italian manufacturer
  • 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.

Forum Users List:
  • Leitz Pro (1 vote, Sideways)
  • Swedex (1 vote, Sideways)
  • Atkinson Walker (1 vote, Sideways)
  • CMT Chrome (1 vote, Sideways)

When looking at different blades, 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.

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 (South Wales)
NLS Tools (London)
Spindex Tools (South England)
Tewkesbury Saw (Southwest England)
Bennet Saw (Southnorth ;))


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.

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

Images were stolen from their respective owners :wink:
Last edited by Trevanion on 28 Dec 2019, 23:22, edited 2 times in total.
By mynamehere
#1316018
Great guide Trevanion, thanks for the write up!

I just googled one of them PCD blades, never heard of 'm before, you don't get much change out of £400,- for a 10" one...

I bought a few router cutters from Wealdon and have been very happy with the quality, they make/sell circular saw blades as well, are they as good as their cutters?

Cheers,

Ferenc
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By Trevanion
#1316025
mynamehere wrote:I bought a few router cutters from Wealdon and have been very happy with the quality, they make/sell circular saw blades as well, are they as good as their cutters?


Wealden certainly make good router cutters but I've never tried their circular saw blades, I have a funny feeling I remember someone mentioning that their blades were made by another company but I could be wrong. They certainly look pretty good value for money.
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By RichardG
#1316031
Very useful guide, thanks.

One question that has always puzzled me is why circular saw blades are sold by the number of teeth and not TPI? A 200mm blade with 80 teeth will be finer than a 300mm blade with up 80 teeth so wouldn’t TPI be better?

Richard
By RobinBHM
#1316039
I personally find blade sharpness is almost more important than blade type for quality of cut.

On a saw bench altering blade height can have quite an impact on breakout.
Blade set low -breakout on upper face
Blade set high -breakout on lower face
Esp noticable on ply or veneered boards.

Ripping solid timber I find the lowest tooth count best to avoid burning.
By John Brown
#1316042
I just bought a all steel blade with 80 teeth for an old hand held circular saw. I bought it for cutting some 5.5mm ply, as the tc blade I had only had about 16 teeth. It's only 160mm diameter, if memory serves. Should I be cautious about this? I didn't realise all steel blades were considered dangerous.
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By Trevanion
#1316043
RobinBHM wrote:I personally find blade sharpness is almost more important than blade type for quality of cut.


I'd like to think if you're buying a new blade it's at least sharp out of the packet! :lol:

It's a good point when your blade begins to get dull though, no matter the type of blade, if the teeth aren't sharp it won't cut properly.
User avatar
By Trevanion
#1316044
John Brown wrote:I just bought a all steel blade with 80 teeth for an old hand held circular saw. I bought it for cutting some 5.5mm ply, as the tc blade I had only had about 16 teeth. It's only 160mm diameter, if memory serves. Should I be cautious about this? I didn't realise all steel blades were considered dangerous.


A new one is possibly not too bad if it has been made to a good standard, I'm surprised you managed to pick one up to be honest. If you're only cutting 5.5mm plywood with it there shouldn't be too much of a worry with using it as it's not really a heavy-load application like ripping down 3" timbers where a lot of strain is put onto the blade where it can cause all sorts of issues.
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By Trevanion
#1316046
RichardG wrote:One question that has always puzzled me is why circular saw blades are sold by the number of teeth and not TPI? A 200mm blade with 80 teeth will be finer than a 300mm blade with up 80 teeth so wouldn’t TPI be better?


I'm guessing it's because they're always a set diameter such as 300mm, whilst say bandsaws can vary in the length drastically between machines so it is better to measure an inch of the blade rather than count 389 teeth on a single blade, since a 300mm blade is always 300mm it is measured by how many teeth are on the whole blade.

Plus it would have to be a radial inch rather than a linear inch.
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By SamTheJarvis
#1316063
Trainee neophyte wrote:I am continually suprise at how much time and effort people will put into this forum, for no obvious benefit to themselves.

Thank you.


I'd like to echo this. Quite a few of my fellow woodworkers don't really pay much attention to their blade choice and it seems to me to be fairly critical to getting good results
By Sideways
#1316175
Excellent post - thanks !
Having needed to buy a selection of new and used blades recently I'd second all the recommendations for (#1) Swedex, Atkinson Walker, CMT Chrome in that order and add Leitz Pro blades at the top of the list as the best of them all.
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By FatmanG
#1322061
Trainee neophyte wrote:I am continually suprise at how much time and effort people will put into this forum, for no obvious benefit to themselves.

Thank you.


The people who make threads like this are heroes IMHO just for the injuries that their efforts prevent. Thankyou very much.