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argumentation
Problems Faced
Countersinking
Using the, Power Saw the accuracy of the
machine is not accurate. The parts needs to be
filed using the filing tool after the part is cut to
get the exact dimension.
The accuracy of the components in the lab is
not accurate. Due to this problem, we have
problems during fitting the screw and bolts into
the holes
The cylindrical block part of the prototype does not rotate fully
when force is applied. The dimensions of the block needs to
be modified using the lathe machine.
Chamfering of the corners of the 2 components (L-shaped
block & Rectangular block) takes a lot of time and effort to
manually cut it using a hacksaw, and then filed using a filling
tool to provide a better finishing to the product.
The straight line welding spool during the welding is hard to
produce during welding the rectangular and L-shaped block
together.
Techniques Used
Countersinking is a technique in which to create a cone-
shaped enlargement cut at the top of an existing drilled hole
to allow the head of a countersunk screw to sit flush with the
surface of the surrounding material.
A conical cutting tool is used in this operation.
The cutter must be properly aligned with the
existing hole. Speed for countersinking is
normally set to much slower than speed used for
drilling hole that is 25% of the drilling speed.
The feed is also light considering the large
amount of surface contact between the cutting
tool and the work-piece. The spindle is lowered
using the hand feed lever slowly and lightly
touch the surface of work-piece. The surface of
work-piece also oiled from time to time. The
work-piece is clamped tightly to the drill press
table to ensure safety of operator and also to
prevent vise movement which would affect the
accuracy of the chamfer hole.