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Technical Support
Advise
Cutting
fluid is so important it cannot be over stressed.
A good quality cutting fluid in a band saw is one of the most
important factors in production cutting.
Good cutting fluid makes cutting go faster, makes blades last
longer and cut straighter, and reduces the cost of operation.
Cutting
fluid performs a variety of important functions in a band saw:
it keeps the chips from welding to the tooth and lubricates the
chips, allowing them to move easily through the cut.
If cutting fluid is unable to cool and lubricate the blade
teeth, the teeth will soften and become dull. The tooth tip must
penetrate the material in order to pull a chip. Without the lubrication of a good coolant, the friction
involved can create temperatures high enough to quickly dull the
blade. If the cutting
fluid is distributed to only one side of the blade, the opposite side
will become dull. This will cause the blade to move toward the side
that has the most cutting fluid and the cut will be crooked.
If we compare sawing to
milling, we immediately see that in sawing there is much less room for
the chip. The chip must
lodge in a small place between the teeth and then be carried smoothly
out of the cut. Without
proper cutting fluid either one of two things will happen.
First, the chip may become welded to the tooth. This will
change the form of the tooth, which, in turn, changes the amount of
force required for the blade to cut. The result is an unbalanced blade
that will produce a crooked cut.
The second possibility is that a chip will wedge in the cut.
Since the chip is work-hardened and harder than the stock from which
it came, the blade will cut into the stock beside the chip.
Again, the result is a crooked cut and a dull blade.
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As indicated earlier, the quality and distribution of the cutting
fluid is a major factor in preventing crooked cuts. Simply squirting
the cutting fluid against one side of the blade or dribbling it on the
top invariably results in uneven cutting fluid distribution with the
effect of dulling one side of the blade and causing crooked cuts.
A more satisfactory system is one that pumps the cutting fluid
into the blade guides on each side of the blade.
This permits the blade to carry the cutting fluid into the cut
on both sides where it can adequately fulfill its function.
By injecting cutting
fluid into both the leading and the following blade guides, the blade
is also cooled and cleaned before and after the cut.
Cutting
fluid prevents chip welding to either the blade or the parent material
by chemical interface. When chips weld to the blade, the tooth form is
changed resulting in cut deviation or lack of penetration. If chips
weld to the parent material, the usual result is a stripped blade.
Note that not
all cutting fluids are suitable for all materials to be cut. Some
cutting fluids tend to cool the blade and the material being cut by
absorbing heat. Heat is always generated because work has occurred
from the cutting action as well as from friction.
Note that when wide material is being cut, the blade gets much
hotter than when narrow material is cut. This happens even when both
materials are cut at the same rate in square inches per minute.
In
summary, the important thing to remember is that high quality coolant
- when properly mixed and applied - pays dividends in any cutting
operation.
If you have additional
questions about this topic, call or e-mail us today.
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