There are many variations of wooden crate designs. By far the most common are 'closed',
'open' and 'framed'. A Closed Crate is one that is completely or nearly completely enclosed
with material such as plywood or lumber boards. When lumber is used, gaps are often left
between the boards to allow for expansion.
An Open Crate is one that (typically) uses lumber
for sheathing. The sheathing is typically
gapped by at various distances. There is no strict
definition of an open crate as compared to
a closed crate. Typically when the gap between
boards is greater than the distance required
for expansion, the crate would be considered an
open crate. The gap between boards would
typically not be greater than the width of the
sheathing boards. When the gap is larger, the
boards are often considered 'cleats' rather
than sheathing thus rendering the crate
unsheathed. An unsheathed crate is a frame crate.
A Frame Crate is one that only contains a skeletal structure and no material is added for
surface or pilferage protection. Typically an open crate will be constructed of 12 pieces of
lumber, each along an outer edge of the content and more lumber placed diagonally to
avoid
distortion from torque.
