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Operation Manual W-4816Z
Model W-4816Z
desired bend angle.
5. Lower the bending leaf, raise the
hold down assembly, and remove the
bent piece part.
6. If you are doing box and pan
bending, choose fingers that closely
match the dimensions of
the finished piece.
BENDING ALLOWANCE
I n o r d e r t o b e n d s h e e t m e t a l
accurately, you will need to consider
the total length of each bend. This
is referred to as bend allowance.
Subtract the bend allowance from
the sum of the outside dimensions
of the piece part to obtain the actual
overall length or width of the piece.
Because of differences in sheet metal
hardness, and whether the bend is
made with the grain or against it,
exact allowances must sometimes
be made by trial and error. However
bend allowances for general use can
be obtained from metal working books
or from the Internet.
U N D E R S T A N D I N G
SPRINGBACK
Springback, also known as elastic
recovery, is the result of the metal
wanting to return to its original shape
after undergoing compression and
stretch. After the bending leaf is
removed from the metal and the load
is released, the piece part relaxes,
forcing the bent portion of the metal to
return slightly to its original shape.
The key to obtaining the correct bend
angle is to over bend the metal a
little and allow it to spring back to the
desired angle. All metals exhibit a
certain amount of spring back.
MATERIAL SELECTION
When selecting materials keep these
instructions in mind:
1. Material must be clean and dry.
(without oil)
2. Material should have a smooth
surface so it processes easily.
3. Dimensional properties of material
must be consistent and not exceed
the machine capacity values.
4. Chemical structure of material
must be consistent.
5. Buy certificated steel from the
same vendor when possible.
L U B R I C A T I O N A N D
MAINTENANCE
CAUTION
It must be determined by the
customer that materials being
processed through the machine
are NOT potentially hazardous
to operator or personnel working
nearby.