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Dimensioning Internal Features
Dimensioning
internal
features
is
done
the
same
way
as
figuring
developed
lengths
or
widths.
Bend
deduction
or
bend
allowance
compensation
has
to
be
used
when
calculating
the
placement
of
internal
fea
-
tures.
Holes
and
cutouts
can
be
dimensioned
on
blueprints
many
different
ways.
Some
of
these
can
be:
from
outside
apex
of
material
of
a
bend,
inside
apex
of
material
of
a
bend,
or
from an outside edge of the part.
In
the
illustrations
below
the
top
picture
is
a
representation
of
a
formed
angle
as
it
would
possibly
appear
on
a
blueprint.
The
hole
and
cutout
is
located
from
the
outside
apex
of
the
material.
Since
this
is
a
ninety
degree
bend
it
is
also
tangent
to
the
bend.
to
calculate
the
placement
of
the
hole
from
the
bottom
of
the
blank
you
would
take
.620
minus
the
bend
deduction
of
.123
and
then
add
1.175
giving you 1.672.
When
you
get
to
the
acute
and
obtuse
bend
sections
remember
that
internal
features
are
calculated
the
same
ways
that
are
used
for
developing
overall
lengths
and
widths.
Just
imagine
that
the
dimensions
used
from
the
bends
to
the
outside
edges
are
going
to
internal features instead.
Use .123 Bend Deduction
FLAT PATTERN SAMPLE 2
Dimensions placed from
top of flat part
FLAT PATTERN SAMPLE 1
Dimensions placed from
bottom of flat part
