Product: Construction Equipment
Bidirectional Corrugation   (+7, -4)  [vote for, against]
More ridged and groovy, baby

Corrugation allows making stronger and stiffer sheets and panels out of less material, at least in one direction. By corrugating in two directions, 90 degrees from each other, the grooves and ridges give additional strength to the cast or pressed glass, plastic, metal or cardboard.

This must have been done earlier, but I haven’t seen it.
-- FarmerJohn, Jan 14 2005

(?) sketch http://www.geocitie...e/corrugation.html?
one pattern [FarmerJohn, Jan 14 2005]

(?) Tessellation origami http://www.sanger.a...llation/tessel5.jpg
Maybe you could use tessellation folding to execute your idea. [robinism, Jan 14 2005]

(?) More origami inspiration http://hverrill.net...ations/testar1c.jpg
[robinism, Jan 14 2005]

A continuous folding process for sheet materials http://citeseerx.is...8&rep=rep1&type=pdf
Rutgers University has a patent pending on a machine to fold chevron corrugations. [robinism, Jan 14 2005, last modified Oct 23 2010]

illustration http://imgur.com/a/bszuS
[xaviergisz, Oct 13 2010, last modified Dec 13 2011]

It might be a pain in the arse to manufacture.
-- DaveW-H, Jan 14 2005


I believe you will give-up diagonal strength.
-- ato_de, Jan 14 2005


[FJ] Corrugations give flexional rigidity against bending / folding at acute angles to the lines of corrugation, and make no difference to forces acting from the side (eg., its easy to roll up a sheet of corrugated iron sideways but impossible lengthways.) Putting another line of corrugations at right angles to the first might make the material like a block of chocalate - easy to break into little squares.
-- ConsulFlaminicus, Jan 14 2005


I still don't think that it could be made effectively...
-- DaveW-H, Jan 14 2005


[r] Nice links. I've done tessellation origami as a hobby without knowing it was called that. Rounded ridges and grooves should give some stability advantages.

[CF] I disagree. The material is equally thick; not at all like a chocolate block.

[DWH] I wouldn't think that embossing cardboard or molding plastic sheeting to be extraordinary.
-- FarmerJohn, Jan 14 2005


A folded version of this has been done successfully. Please see link "A continuous folding process for sheet materials" for details.
-- robinism, Jan 14 2005


you could fold diagonally too but not as easily as widthways in your regular corrugated cardboard.
-- po, Jan 14 2005


Your sketch has ridges but no valleys. I assumed that was an oversight, so I pictured it with valleys. When you picture it with valleys, it looks more like the chevron-folded paper.
-- robinism, Jan 14 2005


Homeless or some future mobile society faction need origami, plastic hinged geodesic style panels that create a single person shelter but can be put together to form a large 'dome' for group meals or other functions.
-- mensmaximus, Jan 14 2005


[robinism- this has been done successfully]

It seems to me that the idea proposed something akin to the little blue trays you get apples and stuff on at the super market...

These are molded/pressed as in the original idea ---what if we try folding instead...

If you try the following with a bit of paper it looks feasible but the x/y-corregation seems to remove all the strength...
- form x-corregations and remove them
- form y-corregates and remove them
- form x/y-corregations and remove them
- squeeze the material to form a bumpy surface

I have to say that I have been unable to get the chevron pattern working. My x-corregations keep interfering with the z ones...

What about corregation of different magnitudes on each axis. In the absence of deformation in the sheet I am pretty sure that the size of possible x-corregations (lets say really small) will influence the frequencey (lets say very low) of possible y-corregations.
-- madness, Jan 14 2005


True... a bit like a box of chocolates... c.f. FarmerJohn.
-- madness, Jan 14 2005


great idea. It's a pity all the links are broken. In the absence of FJ's illustration, I've posted my own. I also investigated intersecting corrugated sheets in my "square helix" idea.
-- xaviergisz, Oct 13 2010


Corugating in a second direction will be at the cost of the strength of the first corrugation... this may or may not be useful.
-- FlyingToaster, Oct 13 2010


I think FJ probably meant what I've illustrated in my third and fourth links. My first and second illustrations were a play on his idea.
-- xaviergisz, Oct 13 2010


//I think FJ probably meant// [+] because I like that we're now discussing the merits of ideas we attribute to [FarmerJohn] without knowing if they're what he actually meant. Like Plato's Dialogues.
-- mouseposture, Oct 13 2010


We might be able to end the speculation by looking at the web archived version of FJ's sketch. The web archive is broken at the moment, but I'll check later today.
-- xaviergisz, Oct 14 2010


Awww spoilsport.
-- mouseposture, Oct 14 2010


Actually it is kind of fun speculating. Having read over the comments, I'm pretty sure my third and fourth illustrations are *not* what FJ meant.

I think he meant a zig-zag pattern of corrugation. I'll probably illustrate this for completeness later today.
-- xaviergisz, Oct 14 2010


Must corrugation in one direction necessarily weaken that in another? Imagine the latitudinal corrugations *tunneling through* the longitudinal ones. Or, to put it another way, imagine peaks of the longitudinal corrugations as railway embankments. Now, run tunnels, or culverts crosswise through them, leaving the crests intact. Now, run latitudinal corrugations through the tunnels.

The result would be topologically complex, but not, I think, impossible to manufacture. There would be four layers. First, a flat substrate. Onto that, glue a fanfold layer, with ridges, say, 2 mm high. That's the latitudinal corrugations. The longitudinal corrugation layer is a 4 mm high fanfold into the underside of which are cut grooves, 2 mm deep, running at right angles to the fanfold, and, like the fanfold, extending continuously from edge to edge. Now, lay the longitudinal corrugation layer onto the latitudinal layer, taking care that the grooves mate with the ridges of the underlying layer. Finally, glue another flat sheet on top, completing the sandwich.
-- mouseposture, Oct 14 2010


I've posted the zig-zag corrugation illustrations. I've checked web archive again and bigsleep is right, it won't retrieve the image.
-- xaviergisz, Oct 14 2010


It's more usual (and thus completely baked), and cheaper and easier, to make corrugated cardboard stronger by making it double-thickness with the corrugations in each layer being oriented orthogonally to each other. So, much as this idea suggests, but made from two thicknesses of cardboard.
-- hippo, Oct 14 2010


I picture plywood but made out of cardboard.
-- cudgel, Oct 14 2010



random, halfbakery