Wilton FK350-2 Manuel D’Utilisation

Page de 44
16
Blade Structure 
For non--ferrous metals, it is common to use 
circular saws with brazed hard metal HM cutting 
edge, consisting of a disc made of alloy tool 
steel (71Cr1) on which the shape of the teeth 
and the seats for the cutting edges are made of 
Widia K10. These saws have shown excellent 
wear resistance but low resistance to impact, 
which is in any case a minor problem with non-
ferrous materials. 
Table 2 
Types of Blades 
The blades fitted to the FK350 and FK350-2SX 
have dimensions 350 x 32 x 2.5 mm and are of 
HM hard steel type since the machine is to be 
used for cutting non-ferrous materials. In 
addition to the size and pitch of the teeth, 
however, the blades also have different 
geometric characteristics in accordance with 
their particular use: 
tooth cutting angle – may be negative or 
positive
tooth sharpening –may be BW
with an 
alternate raked tooth or with a roughing tooth 
raked on both sides and a non--raked finishing 
tooth
tooth pitch – the distance between the crest of 
one tooth and the crest of the next tooth (tooth 
pitch = T) 
Teeth Shape 
”C” TYPE SHARPENING (HZ) 
Coarse toothing with roughing tooth raked on 
both sides and non--raked finishing tooth. The 
roughing tooth is about 0.3 mm higher. 
Coarse toothing with roughing tooth and 
finishing tooth. Used in saws with pitch greater 
than or equal to 5 mm for cutting ferrous and 
non-ferrous materials with solid or solid-profiled 
sections.
Figure 14
”BW” TYPE SHARPENING DIN 1838--UNI 4014 
Coarse toothing with teeth alternately raked to 
the right and left. 
Toothing generally used on cutting-off machines 
for cutting ferrous and alloy materials with 
tubular and profiled sections. 
Figure 15 
POSITIVE AND NEGATIVE CUTTING ANGLES 
The cutting angle
 may vary from positive to 
negative depending on the cutting speed, the 
profile and the type of material to be cut. 
Figure 16 
A positive angle determines better penetration of 
the tool and hence lower shear stress and 
greater ease of sliding for the swarf over the 
cutting edge. On the other hand, the cutting 
edge has lower mechanical resistance, so as the 
breaking load of the material to be cut increases, 
the cutting angle decreases from positive until it 
becomes negative so as to offer a cutting edge 
with a larger resistant section.