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CNC ROUTER ANATOMY
Dust extraction
The bigger the CNC, the more likely that it will
have a built-in vacuum system attached to the
spindle, which cuts down on dust particles in
the room and overall machining mess.
Three-axis CNCs have a few limitations. They
can only cut materials that fit inside the work-
zone and they are unable to make undercuts.
Workzone
Also known as the cut area, a CNC’s workzone
is the portion of the deck where machining can
occur. Deck size determines the maximum
material size that can be placed on the bed, but
the actual workzone is often slightly smaller.
The projects in this book assume a cut area of
4′ × 8′.
Undercuts
Three-axis CNCs can only cut top-down into
the material on the bed. They are unable to
maneuver underneath the material, in order to
cut shapes that overhang or overlap when
viewed from above. You can only make such
features, called undercuts, if you manually flip
the material over to cut the other side.
SAFETY
Routing has some inherent dangers: machines
have moving parts, bits can break, and chips
and other particles become airborne. It’s best
FIGURE 6-3
ShopBot PRSalpha 96″
× 48″ with annotations
of key elements
06/MACHINING FOR DESIGNERS
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