Dating back to ancient times, the first handsaw used by early man may have been simply a piece of jawbone from an animal with teeth intact. From these humble beginnings, the saw has become the inevitable manual tool of every carpentry workshop, which today is still growing, because new saws specialized according to need, which not only cover the cutting of wood, but also plastics, plaster, cardboard, fiber and concrete, among other materials.
It is important to know some basic concepts, as well as the various types of saw available. This knowledge can guide us in the selection of characteristics that will be useful in deciding the suitability of the type of tool What are we searching for. So let’s start with the basics.
Parts of a handsaw
Generally, a saw It has two main components: the leaf and the handle or mango. Viewed from the flat side, the lower edge of the blade, where the teeth are, is called the “forehead” and the opposite side, at the top, is called “loin”. The part of the cutting edge closest to the handle is the “heel” of the blade, while the other end is called “toecap” or “tip”, as if it were a shoe.
However, not all saws are the same, so there are various design features that give them certain properties, for example:
- many kinds of saw, like the one we see in the figure above, have leaves whose width gradually narrows towards the tip. This narrowing is deliberate as it prevents the blade from binding in the wood when making deep cuts.
- Others saws, Like the ones of rib and to dovetail (which we will see later) have a reinforcement along the spine of the blade, as shown in the following figure. This reinforcement called precisely “rib”, provides additional support to the thin blade that might otherwise bend or sag when cutting.
- On the other hand, most of the saws they have teeth set. This means that they are bent laterally at a slight angle to the main body of the sheet. The set is alternative, that is, one tooth to the left, the next to the right, then another to the left and so on (see figure below).
- This set widens the cutting edge relative to the body of the blade, which, again, prevents the saw get stuck when making a deep cut. The width of the cut made by the saw is called “notches”, therefore, the set serves so that the notch is thicker than the blade itself.
- The sheets of saw They can be of two types of material: steel or Fast steel. While the first is the basic type of blade, the second offers greater resistance and number of cuts.
- The number of teeth (or tips) of the blade is very variable, depending on the type of cut that is desired. The more teeth the saw (measured in number of teeth per inch or DPP) the finer and cleaner the cut will be. In general, we can distinguish three types of toothing, as we can see in the figure below.
- In turn, the blade length it also varies, generally, between 160 and 650 mm, depending on the use that will be given to the tool. The greater the length, the larger the cutting surface will be, and this will save us a lot of time.
types of saw
Now that we have seen the main components and characteristics of a saw, Let us know the various types that we can find more frequently in the trade.
a) Universal saws
Possibly the most easily recognizable type of saw, is a popular choice for use on wood boards and panels. Designed for push cut, tend to have thicker blades that taper towards the toe to minimize the overall weight of the blade. tool. Models are available with blades that cut specifically with or across the grain of the wood, and some can do both. The large “D” shaped handle gives the user a firm grip and maximum cutting control.
b) Rib saws
They are designed to cut tongue and groove and make finer, more controlled cuts. They are much smaller than a saw universal and also have much thinner blades, with a length between 250 and 350 mm, and a number of teeth per inch (TPI) between 13 and 15. As they cut by push, the blade must be reinforced to prevent buckling during cutting . This is usually done by adding to the loin of the saw a brass reinforcement (or “rib”), which not only supports the blade, but also adds weight to it. Because of this rib, the saw it cannot make deep cuts, but it does hold the blade in tension, allowing you to make fine cuts. Same as him universal handsaw, the saws rib also have “D” handles and present other known variants:
- Cabinetmaker’s handsaws: Some brands call the rib saw that instead of a “D” handle, it has a light straight handle with four sides to facilitate gripping. It owes its name to the fact that cabinetmakers use it in adjustments and cuts of dovetails and assemblies of all kinds.
Dovetail Saws: it is a reduced version of the rib saw, with a blade length of 200 mm and between 16 and 22 teeth per inch, which are finer and not arranged in the usual way. The width that the blade needs is achieved thanks to the burr that remains with the sharpening of the blade. tool. They are normally manufactured with a closed handle or an open pistol grip. They are especially used for cutting fine joints in hardwoods.
- Precision saws: They are small versions with 26 DPP for cutting delicate pieces.
- Miniature handsaws: they are very thin versions and suitable for model building. The blades have such small serrations, 33 DPI, that they cannot be sharpened and must be replaced directly with new blades.
c) Plywood saws
They are especially suitable for thin and medium materials, such as plywood, laminates and plastics, and have a wide and rigid blade with fine serrations. The tip is rounded and also toothed (in some models, the teeth also cover part of the spine), which allows you to start cuts in the middle of the surface. The hilt is screwed to the blade and can be used as an approximation to mark 45º and 90º angles.
d) Point or needle saws
They have a long narrow blade that is perfect for cutting shapes, curves and tight radii, even in the center of a large board, but is also large enough to make straight cuts. Similar in function to a jigsaw, this type of saw is preferred saw for making exact cuts or working with thin or delicate materials, such as plywood or drywall. Pistol grip fits 8-10 dpi blades.
e) Saws for wood
Besides saws, different types of saws are available for curved cutting of wood, as well as miter saws and saws of pruning that allow the cutting of trees and branches, and that we have already reviewed opportunely in this article. Therefore, here we will briefly mention the hacksaws for carpenters and cabinetmakers that, like the saw tip, they allow curves to be cut.
- Saws: they are extremely versatile as they can be used to make curves in many different types of materials including solid wood and manufactured boards, metals and plastics. They have a frame, usually with an integral handle, which allows the 150mm blade to be held in tension while cutting. The thin 15-17 dpi blade is designed to be discarded once dull and can be mounted for push or pull cutting depending on user preference. The height of the frame determines the depth of cut of the saw.
- Jigsaws: They have a “U” shaped frame that allows cuts to be made in thin manufactured sheets or boards. Unlike the segueta, the blade is very fragile, reaching up to 32 DPI and is extremely narrow, ideal for cutting complex shapes, curves and cutouts, thanks to a design in which it can be set at an angle with respect to the frame.
- Japanese saws: highly specialized cabinetmakers and carpenters make good use of a group of Japanese saws, among which the kataba, ryoba, dozuki Y mawashibiki. Is about tools expensive, with a handle generally made of bamboo and a very thin blade of excellent quality steel, with a high number of teeth and little or no set, which therefore generates a very thin notch. These saws produce a very clean, splinter-free cut, making them a favorite for fine joining work, cutting picture frame molding, tongue and groove, dovetails, and other tasks where finishing details are extremely important. The japanese saws They are also very useful for cutting hard and soft wood, plywood and composite materials, leaving a clean finish to cut surfaces.
Those mentioned are saws of more common use, but there are many other variants that arise, as we pointed out at the beginning, according to the needs of each sector.
However, with all this knowledge, we will have a clearer idea of the saw that suits us best for our work and we can make an easier choice. That is precisely what we will deal with in a future article.