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Cross-ply corrugated cardboard

Stiff in both axes
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Plywood is a laminate material made from several thin sheets of wood, glued together with the grain at different angles (typically alternating by 90 degrees). This makes the board stiff in both planar axes.

Corrugated cardboard is effectively three layers of kraft paper- two outer 'liners', with the central one pleated up and down to form 'flutes'. This makes it stronger, however it has a directionality; it is easier to bend and fold along the flutes.
Double-walled varieties have five layers; flat sheets alternating with corrugations, and higher multi-wall options all exist.

So, all multi-walled cardboard I've seen has the flutes in the same direction. This obviously is sub-optimal for many purposes, since there is increased flexibility and creasing in one orientation.
I suspect this is primarily due to ease of manufacture - corrugating machines are apparently enormous, and produce cardboard at a very high rate. I think that generating longitudinal pleats in a continuous manner may not be straightforward.
Nevertheless, even if this is not feasible I believe that a relatively simple engineering solution may be available. Corrugated cardboard with only two layers -one liner, one corrugated medium ('single face board') is available as an option at some manufacturers.
The strategy requires that we run two manufacturing lines - notionally but probably not literally at right angles to each other. One produces single-wall board, while the other produces single-face board. Potentially these operations may be performed sequentially on the same corrugator, and these intermediates rolled onto reels for storage.
In the final, assembly step, the top layer of the single- wall is glued to the exposed flutes of the single-face board at right angles to its own crenelations. Obviously after this operation the product will not bend well in either orientation and may have to be cut into sheets and stacked for storage rather than rolled up.

Loris, May 04 2020

JP3150617U https://patents.goo...atent/JP3150617U/en
Cross laminated cardboard board [xaviergisz, May 04 2020]

WO2017179896A1 https://patents.goo...t/WO2017179896A1/en
Figure 8 [xaviergisz, May 04 2020]

[link]






       This is a "surely it's a Thing" situation... but a dig around the internet failed to turn up an existing example.
neutrinos_shadow, May 04 2020
  

       It's certainly known in the cardboard construction world. But as a manufactured product, I also couldn't find an example.
bs0u0155, May 04 2020
  

       //in the cardboard construction world// - where exactly are you from [bs0u0155]?
wagster, May 04 2020
  

       "Acoustic Fiberboard" c 1960s- 1980s used this principle; cross-ply corrugated absorbed sound, reducing echoes inside speaker enclosures. AFS/Kriket manufactured it until the early 1980s. Yes, it's very strong.
whlanteigne, May 06 2020
  

       "Acoustic Fiberboard" c 1960s- 1980s used this principle; cross-ply corrugated absorbed sound, reducing echoes inside speaker enclosures. AFS/Kriket manufactured it until the early 1980s. Yes, it's very strong.
whlanteigne, May 06 2020
  

       Above: The "Acoustic Fibreboard" seems to cause an echo.
AusCan531, May 06 2020
  

       Sometimes that is the acoustic effect desired ...
8th of 7, May 06 2020
  

       ////in the cardboard construction world// - where exactly are you from [bs0u0155]?//   

       Given the amount of deliveries I've had, cardboard has become an abundant resource. So, I had a look around the internet and it turns out people use it to build stuff. I had all the things and spare time, now I own a cardboard cat cathedral.
bs0u0155, May 07 2020
  

       That sounds like it could be highly entertaining. Is it anything like Notre Dame ? Does it have smoke detectors and sprinkler systems ?
8th of 7, May 07 2020
  

       [bs0u0155] - That is awesome. And you have finally validated your cats by building them a temple.
wagster, May 07 2020
  

       It has a circular window, but only a single tower at the other end. The tower is accessible from inside and with skill, one cat can climb up inside and emerge on top of the tower, where occasionally treats are to be found. Like a real cathedral, it will soon require some roof restoration. Due to certain leaping down from the tower circumstances.
bs0u0155, May 07 2020
  

       I recommend adding some flying buttresses. And gargoyles.
RayfordSteele, May 07 2020
  
      
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