General meaning of fettling:
• Mostly used for the words related to cleaning,
polishing, and maintaining systems so that they
will be functional or will remain functional.
• The word itself is derived from a root word
referring to “condition,” as seen in the phrase
“in fine fettle,” which is meant to describe good
condition, shape, or health.
Fettling is the means by which a crude casting
is turned into a cost effective quality
component that meets all the standards
required by the customer.
• In context with the casting process, fettling
means the removal of unwanted metal, e.g.
flashings, risers etc.
• It can include processes like chipping,
grinding, shot blasting etc.
• It involves the removal of the cores, gates,
sprues, runners, risers and chipping of any of
unnecessary projections on the surface of the
• Fettling operations can be divided into
Knocking dry sand cores
Removal of gates &
Removal of fins and
Knocking of dry sand core
• Knocking out of dry sand cores. Dry sand cores
may be removed by knocking with iron bar.
• For quick knocking pneumatic or hydraulic
devices are employed, this method is used for
small, medium work. For large castings the
hydro blast process is mostly employed.
REMOVAL OF GATE AND RISER
With chipping hammer
By using cutting saw
With abrasive cut off machine
By using chipping hammer
• It is particularly suited in case of grey iron
castings and brittle materials. The gates and
risers can easily be broken by hitting the
Simple chipping hammer
Pnumetic chipping hammer
With cutting saw
• These saws may be hand saw and power saw
are used for cutting the ferrous like steel,
melable iron and for non ferrous materials
• Mostly the hand saws are used for small and
medium but when power and used for large
POWER OPERATED SAW
With flame cutting
• This type of method is specially used for
ferrous materials of large sized castings where
the risers and gates are very heavy.
• In this the gas cutting flames and arc cutting
methods may be employed.
• big casting.jpg
With abrasive cut of machine
• These machines can work with all metals but
are specially designed for hard metals which
can not be saw or sheared & also where flame
cutting and chipping is not feasible
Removal of fins, rough spots and
un wanted projections
• The casting surface after removal of the gates
may still contain some rough surfaces left at
the time of removal of gates. Like. .
• Sand that is fused with surface.
• Some fins and other projections on the
surface near the parting line.
• They are needed to be cleaned thoroughly
before the casting is put to use.
• The fins and other small projections may
easily be chipped off with the help of either
hand tools or pneumatic tools.
• But for smoothing the rough cut gate edges
either the pedestal or swing frame grinder is
used depends upon the size of castings.
• Traditional and old
• Casting is put in a
chamber and rotated
with 60-70 rpm speed in
presence of small pieces
of white cast iron
• SHOT BLASTING
• TUMBLING WITH HYDRO
• AIR BLASTING