Hacksaw is a hand saw which is mainly made for cutting metal such as steel pipe or metal sheet. It has a C-shaped frame that holds a blade and with a handle at one end. The flame is either fixed or adjustable to fit different sizes of blades. A flexible frame able to accommodate the size of blades ranging from 8 inches to 16 inches. The handle is normally made of wood or plastic. Other mechanisms such as screws will be used to put or attach the blade under the tension. It has fine teeth on the blade and great for cutting the material smoothly. The cutting action of using a hacksaw can be either the pull or push stroke depends on the teeth' direction mounted on the blade. The standard size of a hacksaw is ranging from 10 inches to 12 inches and the blade’s smallest size can be 6 inches. A powered hacksaw is designed in a wide range of size and normally use a larger blade. Hacksaw was originally made for metal cutting, but it can also be used for cutting various materials such as wood and plastic. Many electricians and plumbers often use it to cut plastic conduits and pipes during their works.
In order to use hacksaw effectively and select the right tool for the job, we need to understand the types of blades available. The blade is made of tempered high-grade tool steel, alloyed with other metals. It is classified by its teeth per inch (TPI). A low TPI blade is good for cutting thicker and large materials. It can remove more materials in one stroke. A high TPI blade is suitable for thin objects and it can provide a finer, cleaner cut. Following listed are the main types of hacksaw blades:
1. Course Grade Hacksaw Blade has 14 to 18 TPI and suitable for cutting softer metals and large profiles such as aluminum, mild steel, copper, etc.
2. Medium Grade Hacksaw Blade has 20 to 24 TPI. It can be used for general workshop projects to cut all kinds of material such as tool steel, high carbon steel, cast iron, aluminum, etc.
3. Fine Grade Hacksaw Blade has 24 to 30 TPI. It is mainly used for cutting thin materials like pipes and metal sheets.
4. Superfine Grade Hacksaw Blade has 30 to 32 TPI. It is well suited for cutting extraordinary solid metal and thin metal sheets.
In addition, there are different types of blade settings which is the way teeth are positioned on a blade. The teeth of the hacksaw are bent to the right or left in order to make the cutter wide than itself. This helps to prevent any blocks and provides a good chip clearance during the cutting process. The most common types of blade settings are Alternate sets and Wave sets.
1. Regular Setting (Raker) - One tooth is bent to the right and the next tooth is bent to the left, and every fifth tooth is straight. It is particularly useful for cleaning metal particles. This type of setting works well for softer materials that do not contain iron.
2. Alternate Setting: the teeth are staggered in the alternate setting. One is to the left and another one is to the right throughout the whole length of the blade. For the double alternate setting, two teeth are staggered to the right and another two to the left.
3. Wave Setting: The teeth are set from left to right to show a wave pattern in which few teeth are to the right and a few teeth are to the left. This type of setting is done on the fine grade and superfine grade blade. It is the right choice for cutting both thin and hard metal.
Safety tips for using a hacksaw
We must always have eye protection and glove when cutting the materials. Before starting the works, make sure the blade is rigid, aligned properly, and securely inserted in the handle and flame in the right direction. The next thing is to place the workpiece firmly with a vice especially when cutting a pipe. If it is impossible to join or attach the metal to another object, ensure the workpiece remains secure when another piece has been cut off. When cutting the workpiece, use a slow and steady stroke. Remember not to rush and avoid putting too much pressure on the blade as it may cause the blade to break. The standard cutting speed is around 40 to 50 strokes per minute. And during each cutting stroke, we should always use the entire length of the blade.
Metal-on-metal action may produce a large amount of heat and can easily ruin the blade if it is overheated. We can use oil when necessary to lower down the temperature and reduce friction. After each time usage, clean the saw and store it in a safe place. Never use your hand to brush away the chips, we should always use a brush instead.
When selecting the right blade for your job, it is important to make sure that there is the right combination of the blade and the material. The blade will struggle if you select the wrong TPI and it may also destroy the material. MecHero Malaysia offers different types of the hacksaw and other saw types for meeting your project requirements. You can always contact us at +6011-7000 7687 or email us at my.mechero@gmail.com for an inquiry about the supply of saw tools in Malaysia for industrial usage. As a steel and online hardware store Malaysia, we also supply a wide range of steel materials, general hardware, or mechanical components. Tell us your requirements now and we can advise you accordingly.
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