Baileigh Industrial 1013715, Operator'S Manual

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General Characteristics
Fine Tooth Pitch
– used for thin wall materials such as sheet steel, tubes and profiles.
Coarse Tooth Pitch
– used for large cross-sections, and for soft materials (aluminum alloys and
soft alloys in general).
Determining Proper Tooth Pitch
Proper tooth pitch depends on:
The size of the section.
The hardness of the material.
Wall thickness.
Solid sections call for blades with a coarse tooth pitch,
while small cross-sections require blades with finer
teeth.
When cutting walls of small cross-section
0.039” –
0.275” (1–7mm) profiles, it is important that the number
of teeth actually making the cut should be at least 3
teeth. Otherwise the effect obtained will be one of
tearing rather than of chip removal, leading to a large
increase in shearing stress.
When cutting thick materials or solid sections using an
excessively fine tooth pitch, the chip collects as a
spiral inside the gullet, and since fine tooth pitches
have small gullets, the accumulated chip will exceed
the gullet capacity and press against the walls of the
workpieces, resulting in poor cutting (same situation
with soft materials), greater shearing stress and hence
breakage of the blade.
A larger pitch should be chosen when the shape of the
piece to be cut has a cross-section at any given point
which exceeds the average cross-section.
Cutting and Feeding Speed
The cutting speed and the head feeding speed are limited by the amount of heat generated near
to the points of the teeth. If the head feeding speed is too high, the cut will not be straight in
either the vertical or the horizontal plane.
The cutting speed depends on the strength (kg/mm2) and hardness (HRC) of the material and
the dimensions of the thickest section.
The feeding speed depends on the cross-section of the material. Solid or thick-walled materials
(thickness>5mm) can therefore be cut at high speed providing there is sufficient swarf removal
by the blade, while thin-walled materials such as tubes or thin profiles must be cut with a low
feeding speed.