Talking Tools: Saw Types & Uses

    It's amazing to me, how wood working has been around for thousands of years, but it has never changed so much as the last century.  The hammer and nail, as iconic as it once was, has indeed been largely replaced with screws and glue these days. The saw on the other hand, has never had so much variety, applications, and ease of use as those available today. In fact, I own 9 differing hand saws, two circular saws, two jig saws, a reciprocating saw, two Dremels with multiple cutting attachments, a band saw, a table saw, a mitre saw, an oscillating multi tool with numerous saw attachments, and several saws for pruning my precious fruit trees.

    Sounds like overkill, doesn't it? Well... yes... and no. Because I do a LOT of cutting, and having the right tool for the job saves time. Now, I'm not saying that to scare you off. You can of course, buy the ones you need. But there's a wide range of saws and they each serve a purpose. I want to outline some basic types here so you've got a pretty good idea of the options out there.


    Wood working can usually be broken down into three main activities.

    1. Shaping wood pieces,
    2. Assembling those pieces, and
    3. Finishing the surfaces..... not always in that order.

    As such, the humble saw is perhaps the first tool of choice when shaping pieces. Whether that's cutting the tree down, milling it into lumber, cutting lumber to size, or cutting joined pieces apart. Most people will already know what a saw does. However, just how many types are there? I'll look into a few hand driven saws, then start comparing and contrasting the powered models.

    Hand Saws: A tale of two worlds...

    Hand saws are the ones that run on "elbow grease" (which is a way to say, powered with all the power of at least one human arm). Some have a fixed blade that you'll need to eventually sharpen, whereas others have replaceable blades. Some are designed for quick and rough cutting, while others cut more slowly and smoothly. If you are cutting a piece of timber along the grain, this is called a "rip" cut. If you think of wood as a bunch of parallel fibres (which under a microscope look like straws) you'll realise that to rip the fibres apart from one another is faster than cutting each and every fibre. Blades tailored to this type of cut often have larger (and fewer) teeth with bigger gaps in between (called gullets) to assist clearing out the sawdust generated with the faster cutting style. Conversely, cutting across the grain is called a "cross" cut. Blades tailored to this style of cut often have smaller teeth, often packed closer together. This results in a slower, but much smoother cut. Of course, you can cut cross cuts on rip blade, and vice versa. However, the results might get very ugly, performance on your rip cuts will be slowed as well if you use a cross cutting blade. This can lead to friction burns on the wood, as well as putting more strain on your tools... which shortens it's life expectancy.

    Hand saws don't just cut straight lines either. Some saws, like hack saws, especially those with very fine blades (like "coping" saws) can cut very tight curves, even though the finished result may not be perfectly smooth. However, most saws are geared to cutting straight cuts to a greater or lesser extent. Some blades are designed for cutting very straight to do joinery like dovetails, tenons, and box joints. In this case, the blade often has a reinforced spine, and a particularly high number of small teeth to maximise the straightness, the smoothness and the precise dimensions of the joints, to ensure they're as close-fitting and strong as possible.

    Other blades are designed to cut straight with bent blades. What?! I hear you ask? Well there are "flush cut" blades where you have a flexible blade that bends against a surface to cut any dowels or other attachments off flush, hopefully without cutting into your surrounding surfaces.

    Enter the western saws:

    Interestingly, saws commonly used in the "Western" world such as Europe, America, and the associated colonies, cut most efficiently by pushing the blade forward and down through the wood. Often held parallel to the forearm, the natural position western saws take when cutting timber means the blade angles forward and down when the wood is below shoulder height. This means you cut from the top back corner, to the bottom front. Because they cut on the push stroke, the blades have to be thicker in order to reduce the odds of the blade from bending inappropriately under the compressive force. The thicker blades means more material is removed to make the cut, by grinding out more material, the amount of effort to make that cut goes up as well. Anyone who uses western saws a lot, will often get very tired and sweaty quickly... and those who continue to use it a lot end up with muscles without the gym membership costs.

    A typical western style saw. Please note that this saw has lasted over 17 years, despite being very cheap. It has definitely seen better days, but it'll still cut reasonably well.

    There are some western saw blades called a "backsaw" that don't so much have a thicker blade, but are reinforced with "spines" (thicker metal on the trailing edge). They're not meant to cut pieces deeper than their blade, and are often used for doing shorter, more precise cuts used in joinery such as hand cutting dovetails, tenons, and box joints. Oddly, I haven't seen anyone use these in a long time, and they are specialist tools.

    The brass-spined saws in the foreground of the pic above are typical of your average "backsaw"

    Just to show you how far the rabbit hole goes, have a look at the specifications for the saws above. PPI stands for "Peaks per inch" which is a wacky way Americans differ from the more common "teeth per inch" (TPI) that the British and other "right thinking" cultures do it. Teeth per inch measure the entire tooth, gullet to gullet, whereas peaks per inch will start on the peak, so PPI will often be 1 higher. In essence, 5 TPI = 6 PPI. Also note that the saws are rated more for rip cuts and cross cuts.

    Similar in concept to the backsaw, but different in design, the common hacksaw (sometimes called a "bow" saw) has a surprising range of versatility, and if you want to cut metal and other hard objects, then using a suitable blade on a hacksaw is the best choice. You can also get wood blades for them, and they work well for a lot of things, but the frame of the saw will limit the depth of cut in some situations.

    A typical hack saw. This one has a metal cutting blade on it. Note that it's quite common to use the centre of the blade the most. As you can see by the wear marks. I put white tape on the bow years ago to indicate that it's configured for a metal blade. My wood one has black tape on it.

    Hacksaws are my favourite western saw, and I have two standard 300mm models (one with a wood blade, the other has a metal blade), and a small coping saw, seen here:

    A typical coping saw. This blade is only a few millimetres wide, and this is what enables me to cut really tight corners. However, the blade is only 200mm long, and the bow limits this saw to small pieces. If you want to progress from the coping saw, the next logical step is likely either a very small band saw, or more likely, a scroll saw.

    I also have a standard western style timber saw (seen above), but I rarely use that now that I have Japanese saws... so without further ado...

    Enter the Japanese saws:

    Conversely,  Japanese saws work on completely different design. Japanese hand saws cut on the pull stroke, and are made of a thin piece of flexible but surprisingly springy steel. Japanese saws have a sword or knife-like handle and can be held in numerous ways that range from almost perpendicular to almost parallel to your forearm. The range of movement means you can cut at whatever angle is most comfortable to you. Cutting on the pull stroke means that the blade can be much thinner than western saws, which reduces the amount of removed material and significantly reduces the amount of effort needed to make the cut. The down side is that they are very easy to bend if you get jammed. This is common when western saw users are used to powering through on the push stroke, rather than lightly drawing and pushing the blade through the wood. The good news is, I have yet to find a Japanese saw that doesn't have a replaceable blade, and I've even bent the blade back into shape with a bit of careful straightening.

    Many western wood workers are starting to adopt Japanese blades into their tool boxes. They're easier to use, they cut with less material lost (less dust, and less lost wood) and when using the correct blade, cut amazingly smoothly. I haven't seen a Japanese blade that works to cut metal or other harder materials, but that's where the usual western hacksaw comes in. Despite this, Japanese saws come in a range of types, and I'll briefly explain the differences:

     

    A Ryoba saw. If there is one Japanese style saw to try, I'd honestly say this is it! Note the fine teeth on the bottom edge, the larger teeth on the top edge, and the removable handle.

    • Japanese Saws:
      • Ryoba: "Ryouba/Ryoba" means "double edged or double blade". This is effectively two saws for the price of one. One side (big teeth) is for rip cuts, and the other (small teeth) for cross cuts.
      • Dozuki. "Dozuki" roughly translates to "shoulder cut". It is the Japanese equivalent of a "back saw", and is used for where accuracy and smoothness matters. It's usually used to cut fancier cuts.
      • Kataba Yokobiki. “Kataba” translates as “cutting on one side;” “yokobiki” is Japanese for “crosscut.”
      • Azebiki: A smaller version of a Ryoba, but the main difference is that it has curved saw edges so you can cut from surfaces, instead of edges.
      • Mawashibiki: Translated into "Turning cut" this saw features a single edged, extremely narrow blade is designed to cut curves from a edges and pre-made holes. It's the Japanese equivalent of a western keyhole saw.

     

    Side note, Kerf, and compound kerf:

    Like many credit cards with numerous fees and other charges, each individually too small to worry about, but over time, those charges, like kerf add up, literally.

    Regardless of the type of saw, or thickness of the blade, the thickness of that cut is obviously going to be the same width as the blade. The groove that has been removed is called the "kerf". Many newbie woodworkers (including yours truly) who start to cut numerous pieces from a single board or sheet fail to consider the loss a saw's kerf can make. For example, if I have a standard 2400mm x 1200mm sheet of ply wood. (Roughly 8' x 4' for those in imperial-driven lands) and I decide to make a bunch of 50mm high drawers for my wood screws, nails, washers, etc. I need to cut four 50mm high pieces of wood for the front, back and sides for each drawer. So I start ripping the 2400mm length into 50mm wide strips. How many would I get from the 2400mm? Basic maths (2400 divided by 50) says I should get 48 strips but that hasn't allowed for the kerf of my saw blade. Now if I am using your average western saw, I'll probably lose 1.5mm to 2mm each strip, and that's assuming I'm cutting perfectly straight and parallel each time. So all of a sudden each strip needs 52mm of wood, (allowing for the 2mm kerf) which means I get 46 strips. I've just lost 92mm of wood by making 2mm cuts 46 times. Actually, because I have 46.15 strips worth of wood, I lose a further 2mm on a 47th to make sure the 46th strip is the right 50mm size. Total loss of wood, 94mm that has been magically turned into sawdust... and that's only if they are perfectly parallel and straight. This is why people like table saws... but we'll get to that a bit later.

     

    Powered Saws:

    There are over 10 powered saw types, that fit into two broad categories, hand held, and stationary.

    • Hand held powered saws:
      • Circular Saw
      • Track Saw
      • Jig Saw
      • Reciprocating Saw/"Sawsall"
      • Multi tool/Oscillating tool
      • Rotary tools with cutting attachment (Dremel)
      • Chainsaw
    • Stationary powered saws:
      • Table saw/Cabinet saw
      • Band Saw
      • Scroll Saw
      • Mitre Saw
      • Radial Arm Saw
      • Panel Saw
      • Cut-off saw
      • Mill

    The circular saw:

    Circular saw

    Arguably the most common of the powered saws, and one of the oldest types. These saws feature a spinning circular blade and a motor, attached to a base, and a retractable guard to protect you from the obvious dangers a powered spinning blade can pose. Circular saws cut straight lines pretty well, but over longer distances the cuts can curve a bit. Most circular saws have a depth and angle adjustment, so you can make beveled cuts. If rough cutting your timber for garden beds, and anywhere the wood is too heavy to move, but not so thick you need a chainsaw, this is a good choice.

    Circular saws aren't precise tools, and most have do not dust extraction whatsoever, so expect to make a mess wherever you use these, and protect eyes, ears, and lungs. The cuts can be a bit rough, especially if pushing the saw too quickly for the blade to eject the dust effectively. In the past, most circular saws were corded power tools. These days, high capacity Lithium batteries make cordless models possible.

    The track saw:

    In short, it's a circular saw, that runs on a track to ensure that the cuts are straight. These often feature the same depth and angled cuts of the circular saw, but often with a finer blade which cuts far more cleanly. More expensive models also include dust extraction ports for a cleaner and less hazardous experience. However, they're often far from cheap. With typical circular saws ranging from $59-$289, track saws can come in at $500+ and some go over $1000!

    You can buy third-party tracks, or make your own to adapt a typical run of the mill circular saw into a track saw. I often get by using a 1.8m spirit level clamped to the board, and run my saw along it. I then cut the more manageable pieces on the table saw to more precise dimensions.

    Tracks often come in pieces, that range from 700-1200mm long have to be assembled, then clamped to the board, the cut is then made, then the whole unit has to be moved again and clamped to make another cut. In short, the track saw is a bulky item to store and carry, as well as a cumbersome, and time consuming tool to use if many cuts are needed. However, the advantage is the complete freedom to cut a sheet of wood at any angle. You're not limited to parallel and perpendicular cuts to the edges.

    The next evolution of the circular saw family is either the mitre saw (for easy angled cuts), the table saw (for easy parallel, repeatable cuts of specific widths and depths). Or perhaps, most similar, is the panel saw. See below for more details.

    The jig saw:

    This is what happens when you combine a keyhole saw with a sewing machine.This is the cheapest power tool that will allow you to make curved cuts.

    jig saw

    Featuring a narrow blade that moves up and down, you can cut some amazing curves with this device. With replaceable blades up to 100mm long, you can cut metal (albeit slowly) some plastics (at slow speeds to avoid melting) or wood. One key piece of warning, the depth of the cut must not exceed the blade's depth at it's highest (not deepest) point. Otherwise the blade will hit the bottom of the hole and bend the blade. If your jig saw suddenly starts bucking, or bouncing around, either the blade has jammed on the sides, or you've hit the bottom while cutting timber that's too thick.

    Jig saws aren't renowned for clean cuts, it's often best to cut a little wide, and either sand or cut the excess off with a more precise device to the the exact dimensions.

    The curve-cutting wood worker has a few options to upgrade to from the jigsaw, the reciprocating saw (also known as a "sawzall", coming next), or for stationary workshop tools, there's the venerable band saw, and the scroll saw, which I'll mention below.

    The reciprocating saw (a.k.a: "Sawsall/sawzall"):

    reciprocating saw

    This tool is definitely built with the same principles as a jig saw, but with demolition and dismantling in mind. This is an amazingly versatile tool for cutting rough holes in gyprock ("plaster" or "sheet rock" in other countries) for installing power outlets, switches, and of course, cutting damaged parts out for replacement. The reciprocating saw features blades up to 150mm long and can cut wood, nails, screws with ease. I originally got mine for easy disassembly of pallets, I'd just tap the boards so there was a 2mm gap, then I'd just stick the reciprocating blade in the gap and cut the nails. I've also used it to remove the falling ceiling in our garage, and it very easily cut through the gyprock, the metal battens, electrical wires, and even a light socket in the space of a few seconds.. so make sure you don't have any dangerous wires, communications lines, gas pipes, etc when cutting into walls and ceilings.

    This, like the jigsaw, is not a clean cutter. Make sure you can either smooth the cuts down, or hide it behind a panel. Wear full safety equipment, goggles, ear protection, and dust mask because this can kick up a lot of dust.

    The rotary tool (a.k.a: "Dremel"):

    Dremel with metal cutting wheel attached.

    The rotary tool is a fantastic addition to the tool kit for people working on small projects. It can be turned into a small scale router, drill press, sander, grinder, engraver, and of course, a small power saw. When the cutting blades are only a little over 1" in diameter, you can't expect this to cut large boards, but it can definitely cut wood, nails, screws with the right attachments. It's quite ironic that the corded Dremel models are roughly the same diameter as (or wider than) the saw blades, so it can be impossible to use in some situations "out of the box". So either get the flexible extension, or the right-angle adaptor to make cutting easier in these situations. I'd also recommend that you buy your accessories in the kits as they are significantly better value. Oh, and ditch the collet system and get yourself a chuck. It just makes your life so much easier.

    The oscillating tool/multi tool:

    Where the Dremel operates on small projects, the oscillating/multi tool is also considered to be at the smaller end, but as a saw, it works in places that no other powered saw can. The oscillating tool is a relatively recent invention, and surprisingly safe. You see the vibrations of the blade are great cutting wood, or even tiles because they are rigid materials, but they are not good at cutting fingers as the flesh just wobbles with the blade. Fair warning though, finger nails, are an entirely different story.

    Able to sand, grind, cut, and carve, the oscillating tool isn't a dedicated saw per se, but the cutting attachments can be surprisingly effective in tight spaces.

    The chainsaw:

    Lacking any semblence of a smooth cut, chainsaws are renowned for being the tool of choice for felling trees. They're also used to reduce logs into manageable pieces like firewood, or in some conditions, mill logs into lumber (with the right rig). Interestingly, this rough & ready device has also found its way into the "power carver" scene. Artisans carve sculptures very quickly with chain saws at first to get a rough shape, then can use smaller tools to add fine detail.

     

    I'll start writing about the workshop saws when I get a chance. More to come!

    Stay safe and happy sawing!

    Ham.


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