Gerima SMA 50?E1 Operating Manual page 21

Indexable cutting inserts for radius milling
Notes on radius milling:
Choosing the right guide bearing to ensure the
correct lateral position of the radius is just as
important as setting the correct height of the
guide plate.
If the wrong guide bearing is used, the machined
radius will not form a smooth transition with the
end face of the workpiece.
If the guide bearing used is too large, the ap‐
pearance of the resulting radius is similar (but
rotated by 90°) to that created when the guide
plate is set too low.
If the guide bearing used is too small, the ap‐
pearance of the resulting radius is similar (but
rotated by 90°) to that created when the guide
plate is set too high.
The same phenomenon arises if the end and up‐
per faces of the workpiece are not aligned at
right angles to one another.
If the edge of the workpiece to be machined was
created by cutting a larger plate with a plasma
cutter, the upper and end faces of the workpiece
may be out of rectangular alignment by as much
as 7°. This type of misalignment will result in a
radius that is either incomplete or that cuts too
far into the material depending on whether the
upper or lower surface of the workpiece is being
machined.
Although our conically shaped guide bearings
are designed to butt up against the workpiece
immediately below the cutting inserts and can
therefore minimize the problem,
they cannot eradicate it entirely.
Machining a correct radius there‐
fore requires a 90° angle between
the adjacent faces of the workpiece.
Guide bearing too large (radius incomplete)
Guide bearing too small (radius cuts into material)
Angle greater than 90° (radius incomplete)
Angle less than 90° (radius cuts into material)
21
V.02 .22.03.10.ENG
too large
too small
> 90°
< 90°