EIGHT BASIC CNC JOINT CONDITIONS
FIGURE 2-22
An exploded view of a
tabletop is an example
of a three way connec-
tion
7: THREE-WAY
Three-way connections occur by integrating a
third plane atop a through connection (or ser-
ies of through connections). The tabs on the
crosspieces intersect a slot in the top plane.
This yields a diaphragm structure that is
strong, rigid, and lightweight. Edge-to-edge-
to-edge connections and end-to-face-to-edge
connections are similar to three-way connec-
tions in that all are made up of composite
aggregations of fingers, slots, and tabs.
In structural engineering, a diaphragm is a
basic element that distributes the hori-
zontal load across the other parts of a
structure.
FIGURE 2-23
This exploded diagram
of a nesting pedestal
demonstrates a four-
way connection
8: FOUR-WAY
A three-way connection becomes a four-way
connection when a fourth plane is added
below the through connection. This creates a
torsion box where each plane is braced in all
directions (see “Structures” on page 56), and
loads and forces are distributed into the top
and bottom planes. This produces an
extremely strong and stable assembly.
52
DESIGN FOR CNC
