Gullco KBM-28 - Manual (Page 32)

28
CUTTER BREAKAGE CAUSED BY EXTERNAL FORCES
In most cases the cutter will break when one or a combination of the external forces, P2 through to
P6 described on the previous page, is applied beyond the limit of the cutter.
Exceptionally heavy stress may be applied to the cutter by moments P3 and P4. These moments
apply a lever action upon the cutter as shown below. The extent of these moments are dependent
on the length of the plate extension, indicated as L1 on the drawing on the previous page.
To avoid situations that will cause external forces to break the cutter, the following recommenda-
tions are made:
1. Use a support table and conveyor system when moment P3 or P4 is great (bench mounted
operation with large, heavy plates, or plates with a long extension L1).
2. Use a pinch roller and roller conveyor to improve the feeding force F2 and minimize the
interference force P5 (bench mounted operation with large, heavy plate).
3. Use a caster assembly to minimize the pulling force P2 away from the cutter (self propelled
operation).
When the KBM
®
-28 is used as a bench/floor mounted unit to bevel the short sides of rectangular
plates such as that shown in the diagram below, the plates should be supported on additional work
tables. Otherwise, a twisting force (A) will give a heavy side stress to the cutter and cause
breakage. Always feed the material square to the machine. As previously mentioned, the greater
the unsupported length L1, the greater the moment P3 or possibly P4, creating an undue load to the
cutter. Therefore it is important that even narrow width plates with a length of 20" [508mm] or more,
be supported by some form of work table and, or, clamp roller system.