We will see about hacksaw used for which purpose and hacksaw definition and uses So without wasting any more time move towards our topic.I already write about engineers files and types of files. you should have idea about this it will help you to enhance your knowledge about workshop technology.
The hacksaw
hacksaw is generally used for cutting of metals.Where large amounts of metal waste must be removed, this is done more easily by hack sawing away from extra metal rather than by depositing.
Hacksaw Definition
hacksaw is a hand tool which is used for cutting of metal.
Construction and working of hacksaw
If the work-piece is left a little too large, then a file can be used to obtain the final size and surface.
The hacksaw blade fits into a hacksaw frame on two holding pins, one of which is adjustable to tension the blade. The frame of the hacksaw should be rigid, keep the blade in correct alignment, stretch the blade easily and have a comfortable grip.The blade is mounted on the frame with the teeth pointing away from the handle and is properly stretched by turning the butterfly nut to take over, and then by applying only three rounds. A loose blade twists or loops and does not cut straight,while a too tight blade could pull the ends of the blade.Diagram of hacksaw is shown in given figure below.
Standard Hacksaw blade
The standard size of hacksaw blade is 300 mm long, 13 mm wide, 0.65 mm thick and is
available with 14, 18, 24 and 32 teeth per 25 mm.
How hacksaw blade is chosen
A hacksaw blade should be chosen depending on the type of material to be cut, whether
hard or soft, and the nature of the cut, whether thick or thin section.
Two important the factors in choosing a blade
- The pitch,
- And the distance between each tooth and the material from which the blade is made.
When cutting soft metals, more material will be removed with each stroke and this material must have a place to exit. So only place where the material can exit is between the teeth, and therefore if the teeth are further apart, there is more space for the metal to be cut.
The largest gap is in the blade with the least teeth, i.e. 14 teeth per 25 mm. the reverse is true when cutting harder metals. Less material will be removed with each stroke, which will require less space between each tooth. If less space is required, more teeth can be put into the blade, more teeth cut and the time and effort in cutting will be less. When cutting thin sections such as plate, at least three consecutive teeth should always be in contact with the metal or the teeth will overlap the thin section. So the teeth will have to be closer, which means more teeth in the blade, that is, 32 teeth per 25 mm.
Like a file, the hacksaw cuts on the forward stroke, which is when the pressure needs to be applied. The pressure must be released on the return stroke. Do not rush, but use regular long strokes (about 70 strokes per minute when using high-speed steel blades). The same balanced position should be used as for the deposit.
Selection of hacksaw blades
Selection of hacksaw blades with the respect to the metal thickness table of hacksaw blades selection is given below .
Types of hacksaw blades
Here is the complete 3 types of hacksaw blades are given below:
- All hard hacksaw Blade
- Bimetallic hacksaw Blade
- Flexible hacksaw Blade
1. All hard Hacksaw Blade: : All hard types of hacksaw is made up of hardened high-speed steel.Due to its hardness this blades have long blade life but it can be easily broken if twisted during sawing.Due this this major reason this hacksaw used by skilled person.
2. Bimetallic Hacksaw Blade: This type of blade has a thin, thin cutting strip. High speed steel is attached to a hard alloy-steel by electron beam welding. The blade combines the hardness properties of all-hard blades and the unbreakable properties of flexible blades, resulting in an unbreakable blade with longer life and faster cutting properties.
3. Flexible Hacksaw Blade :This type of blade is also made of high speed steel, but only with hardened teeth. The result is a rigid and flexible blade tooth that is virtually unbreakable and can therefore be used by a less experienced user or when viewed in an awkward position. The useful life of the blade is reduced due to the problem of hardening only the teeth.
Conclusion
I hope you had definitely get useful information about Hacksaw,Uses of hacksaw,definition of hacksaw and also Types of hacksaw. If you have any related question about this topic then i will recommend you please share with us by commenting below.
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