Cincinnati 175 CB - Bending Tips; Gaging

L .063" - .125"
FIGURE 30
BENDING TIPS
Making gooQ. bends is an. art. The following suggestions will
help in making the best possible bends.
Whenever possible locate the tooling and the bend load on
the front-to-back and left-to-right machine centerlines.
Some jobs may require shimming of the dies to correct for
machine deflections or die wear. This is usually done by
using thin metal· or paper, .002 to .004 thick, starting with
a long strip and then centering successively shorter ones
on top. This "tapering" procedure may be used to produce
'~Tery accurate bends. The recommended place to shim is
under the filler block or lower die.
A bend difference between the two ends of the part usually
indi~ates worn dies or die errors. This problem can easily
be cocrected by tilting the ram.
Always .make sure the die shoulders are seated tightly
against th.? ram nose and the filler block. Check for burrs
when instaUing tooling.
Front-to-back die alignment is critical in producing uniform
bends and in eliminating damaging thrust loads.
When forming with bottoming dies the amount of applied
machine tonnage will affect the bend. If. the machine is
equipped with tonnage control it may be necessary to try
different tonnages in establishing the best possible bend.
Selecting tooling which is correct for the job and compatible
'with the machine capacity is essential for making good
bends.
Always inspect the tooling before starting a new. job. It
may be impossible to compensate for badly worn dies and
they could create a safety hazard.
Two additional considerations for making good bends are
gaging and blank development.
21
GAGING
Proper gaging is just as important as tooling and the press
brake when attempting to make good parts. Each part
should be individually analyzed for the best bend sequence
m~~d. .
Selecting Proper Gage:
A. Make a simple sketch showing the operation sequence of
the bends.
B • Determine the gage locations using the part edge or the
previous bend to hold the bes t accuracy and part
tolerance. Sometimes holes are used for gaging.
C. When using backgages, provide a material stop -of
sufficient height and size to minimize the possibility of
the workpiece passing beyond the back gage , which
would allow your hands to enter the point-of-operation.
D. Lot sizes, production requirements, shop methods and
available $$$ have also had a bearing on the selection
of gages.
E. PT sheets 601, 602, 603, 604, 605, 606, 608 and 609
give many examples of methods of gaging using
. CINCINNATI gages.
Figure 31 illustrates some examples of standard
CINCINNATI gaging.
CINCINNATI Standard Gage with micrometer
adjustment.
CINCINNATI Heavy Duty Gages are particularly
recommended for use in plate shops, where very
rugged construction is necessary. Gages equipped
with heavy duty stops are shown.
FIGURE 31