A junior hacksaw (also referred to as a mini hacksaw) is basically a smaller version of a regular hacksaw.
Application
Junior hacksaws are commonly used for cutting through metal pipes or plastic tubing.
The blade of a junior hacksaw is much smaller than a regular one, so the tool can be used for more precise cutting or for applications that require a neater finish.
Because of its size, a junior hacksaw also allows you to work in more confined spaces, where a regular hacksaw wouldn’t fit.
Material
A junior hacksaw is designed for cutting very thin metal and plastic.
Characteristics
Blade
Like a regular hacksaw, the blade on a junior hacksaw can be removed from the frame, however, in terms of size, a junior hacksaw blade is much smaller and thinner
Blades are usually 150mm (5.9″ approx.)
Pins
If you look closely at a junior hacksaw blade, you will see that is has two tiny pins, one on either end of the blade. These pins allow the blade to be held in the frame.
Cutting stroke
A junior hacksaw cuts on the push stroke, which means the blade should always be placed in the frame with the teeth pointing away from the handle.
Junior hacksaw blades have very small teeth with relatively shallow gullets, so they cut and remove less material with each stroke. This means cutting with one may be a slower process, but the user has more control over the depth and direction of each cut and a neater finish will be produced
Tooth form
If you turn a junior hacksaw blade on its side, you will see that the teeth are set in a wavy line. Manufacturers claim that the teeth are set in this way in order to make a cut that is wider than blade, in order to prevent it becoming stuck in the material.
Teeth Per Inch (TPI)
Like regular hacksaw blades, junior hacksaw blades will usually have between 14 and 32 teeth per inch.
Generally, blades with 18 teeth per inch or less, will be more suitable for cutting plastic and soft metal. Blades with 20-32 teeth per inch will be more suitable for cutting steel.
The more teeth per inch a blade has, the slower it will cut, but the neater the finish will be.
Handle
Most junior hacksaws have what’s known as a straight handle. This type of handle is usually found on saws used for delicate or precise work, such as back saws or coping saws.
The handle can be turned freely in the user’s hand, meaning you have greater control over the cuts you make.
Saws of this kind will not generally be used for fast aggressive cutting, as it is harder to apply force to the saw with this type of handle.