Aura LM-270, Manual

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15
Blade Structure COMBO TOOTH
Pitch varies between teeth and consequently varying teeth
size and varying gullet depths. Pitch varies between teeth,
Bi-metal blade are the most commonly used. They consist of
which ensures a smoother, quieter cut and longer blade life
silicon-steel blade backing by a laser welded high speed steel
owing to the lack of vibration.
(HSS) cutting edge. The type of stock are classified in M2, M42,
M51 and differ from each other because their major hardness
due to increasing percentage of Cobalt (Cc) and molybdenum
(Mo) contained in metal alloy.
There are several key factors to consider in choosing a blade
:
Tooth Pitch---The number of teeth per inch
(
TPI
)
on the
blade
,
also known as tooth pitch
.
Select a pitch
which will assure that at least three teeth are
contacting the workpiece while cutting
.
This helps to
Another advantage offered in the use of this type of blade in
distribute the cutting forces and avoids tooth
the fact that with an only blade it is possible to cut a wide
breakage
.
range of different material in size and type.
Tooth Form---There are four common forms of teeth on the
COMBO TOOTH
blade
:
buttress
,
claw
-
tooth
,
precision and tungsten
O O
9 -10 positive rake
carbide
.
Precision is the most common and is the
type supplied with this saw
.
Tooth Set---Set is the degree to which the teeth are bent
away from the blade
.
Typical tooth set styles are
raker
,
wave and straight set
.
Always select and use good
-
quality saw blades and choose
the right blade for the job
.
Discuss your cutting
requirements with your saw blade dealer to make sure you
are getting the type of blade which best suits your need
.
Poor quality blades and improper use are often the cause
This type of blade is the most suitable for the cutting of
of premature blade failure
.
section bars and large and thick pipes as well as for the
cutting of solid bars at maximum machine capacity. Available
Many conditions can lead to breakage
.
Blade breakage is
,
in
pitches: 3-4/4-6.
some cases
,
unavoidable
,
since it is the natural result of the
peculiar stresses that bandsaw blades are subjected to
.
Sets
Blade breakage is also due to avoidable causes
.
Saw teeth bent out the plane of saw body, resulting in a wide
Avoidable breakage is most often the result of poor care
cut in the work-piece.
or judgement on the part of the operator when mounting or
adjusting the blade or support guides
.
The most common
Regular or Raker Set
causes of blade breakage are
:
Cutting teeth right and left, alternated by a straight
tooth.
(1) faulty alignment and adjustment of the guides
;
(2) insufficient number of teeth contacting the cut
;
(3) feeding too fast
;
(4) tooth dullness or absence of sufficient set
;
Of great use for materials with dimensions superior to 5mm.
(5) excessive tension
;
Used for cutting of steel, castings and hard nonferrous
(6) using a blade with a lumpy or improperly finished
materials.
weld
;
and
(7) continuously running the bandsaw when not in use
.
Wavy Set
REGULAR TOOTH
Set in smooth waves.
O
0 rake and constant pitch
This set is associated with very fine teeth and it is mainly
used for cutting of pipes and thin section bars (from 1-3mm).
Most common form for transversal or inclined of solid small and
Alternate Set (in groups)
average cross-sections or pipes, in laminated mild steel and
Groups of cutting teeth right and left, alternated by a
gray iron or general metal.
straight tooth.
POSITIVE RAKE TOOTH
O O
9 -10 positive rake and constant pitch
This set is associated with very fine teeth and it is used for
extremely thin materials (less than 1mm).
Alternate Set( individual teeth)
Cutting teeth right and left.
Particular use for crosswise or inclined cuts in solid sections or
large pipes, but above all harder materials (highly alloyed and
This set is used for the cutting of nonferrous soft materials,
stainless steels, special bronze and forge pig iron).
plastics and wood.