Today we will discuss about difference between up milling
and down milling. The milling is a machining process in which, a rotary cutter is
used to remove the material from work piece in the direction perpendicular to
the axis of rotation. The milling process is done by the machine, which hold both
the tool and work piece in jig and fixture, known as milling machine. There are two ways to cut the material from the work piece through milling machine. First one is named as conventional milling or Up milling and the other one known as climb milling or down milling. The main and basic difference between up milling and down milling is the direction of rotation of cutter to the feed.
The milling operation is used to facing of those work piece, which are not symmetrical from its axis. It is also used to cut pockets, drill, slot and shape the work piece according to the requirement.
The milling operation is used to facing of those work piece, which are not symmetrical from its axis. It is also used to cut pockets, drill, slot and shape the work piece according to the requirement.
There are two ways to cut the material from the work piece
through milling machine. First one is named as conventional milling or Up
milling and the other one known as climb milling or down milling. The main and
basic difference between up milling and down milling is the direction of rotation
of cutter to the feed.
In up milling the cutter is rotate clockwise when cutting
the work piece from right to left. In this type of milling the tool spins against
the direction of feed. In this milling process, the cutting chips are carried upward by the tool.
Image Source : http://mmu.ic.polyu.edu.hk/handout/0103/0103.htm
In down milling, the cutter rotates clockwise while
cutting the work piece from left to right. In this milling operation, the tool
spins with the direction of feed. The cutting chips are carried downward by the tool.
Image Source : http://mmu.ic.polyu.edu.hk/handout/0103/0103.htm
Difference between Up milling and Down milling:
Up Milling |
Down Milling |
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1.
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In up milling the cutter rotates against direction of feed.
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In Down milling, the cutter rotates with direction of feed.
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2.
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It is also known as conventional milling.
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It is also known as climb milling.
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3.
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In this, chip width size is zero at initial cut and increase
with feed. It is maximum at the end of feed.
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In this cutting process, chip size is maximum at start of cut
and decrease with the feed. It is zero at the end of feed.
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4.
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In this process, heat is diffuse to the work piece which
causes the change in metal properties.
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In down milling most of heat diffuse to the chip does not
change the work piece properties.
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5.
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In up milling, tool wear is more because the tool runs
against the feed.
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In this, tool wear is less compare to the up milling, due
to the cutter rotate with the feed.
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6.
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Tool life is low.
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Tool life is high.
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7.
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The cutting chips are carried upward by the tool so known
as up milling.
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The chips are carried downward by the tool so known as
down milling.
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8.
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The cutting chips fall down in front of the cutting tool
which again cut the chips cause less surface finish.
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The cutting chips fall down behind the tool. This gives
better surface finish.
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9.
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Due to upward force by tool, high strength zig and fixture
required to hold the work piece.
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In down milling, downward force act on work piece normal
zig and fixture required.
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10.
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It is the traditional way of cutting the work piece.
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It is non-traditional way, but now days, down milling used
more than up milling.
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11.
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High quality cutting fluid is required because heat
diffuse in the work piece.
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In this process heat does not diffuse in the work piece,
so simple cutting fluid is required.
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12.
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It required high cutting force compare to down milling.
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It required low cutting force.
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Today we have learnt about difference between up milling and
down milling. If you have any query or doubt, ask by commenting below.