Stacking Strength

[BIISCOOPS]

I was wondering if anyone knew how to determine the stacking strength of a standard 601 cleated plywood crate?

[Paul W. Vieira]

There are a couple of ways to estimate the stacking strength of a 601 style A or B crate.
1. If a 601 (now known as ASTM D 6251), style A or B only, is built exaclty
as specified in the specification, for a maximum load of 1000 pounds, will
support its own loaded weight when stacked by an identical crate and load.
2. Build a proto type with a dummy load and send it to a packaging test lab
for a compression test.
3. The most complicated method is to perform the mathmatical calculations combining the panel axial strength in compression and the added support of the cleating material.

Because there are so many variables that can apply to a wooden crate, it is extremely difficult to determine the correct stacking stength for any specific crate. Some of the variables are: plywood thickness, panel size, with and thickness of cleat material, bottom construction, just to name a few variables.
When in doubt, move to the side of safety and upgrade your plywood and cleats. When exceeding a 1000 pound load, you may need to change crate style.