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or misuse of techniques shown in this web page. We simply publish information
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When is a 5 axis machining center required?
Though I don't want to over-simplify this sophisticated type of equipment,
there are only two types of five axis machining applications (in very general
First, many companies must simply expose different surfaces (planes) to the
spindle for machining. Such would be the case on a very odd shaped workpiece
that must be machined on several sides. In one sense, this kind of machining is
simply an extension of what can be done with the fourth axis. If this is your
area of interest, you'll want to learn more about "variable plane
selection". This feature is like the standard G17, G18, and G19 (XY, XZ,
YZ) plane selection commands, but it allows you to define any plane for
machining. This allows you to use many of the standard programming features
like canned cycles, cutter radius compensation, and axis rotation, making
programming much easier.
Second (and the more classic type), when machining elaborate 3d shapes, as
would be the case with injection molds and edm electrodes, it is important to
keep the cutting tool perpendicular to the machined surface during machining.
This requires five axes of motion (three linear, two rotary). Note that this
kind of machining is always so sophisticated that it requires a cam system to
prepare programs, and the cam system does all the hard work related to figuring
out the axis motions.
When it comes to how the additional two axis are actually handled on the
machine, again there are only two ways. First, with smaller machines, the
rotary axes are commonly handled with rotary tables. The workpiece is rotated
to achieve which ever type of five axis machining you're doing. Note that this
kind of machine is especially suited to the first type mentioned above, since
there are no limitations to rotation (full 360 degrees in both rotary axes),
and many surfaces can be exposed for machining.
Second, when the machine becomes so large that it is infeasible to rotate
the workpiece (as is the case with gantry mills), the two rotary axes are
incorporated into the machine's headstock. The tool actually tilts in two
directions. There will always be a limitation to how much the tool can tilt,
which also tends to limit the application for this kind of machine to 3d work.
Frankly speaking, there's not that much more to five axis machining. Again,
you'd need to look into variable plane selection if you will be doing the first
type of five axis work, but I know of no other major topics for discussion. If
anyone has more information to relate, we welcome your comments.