> If we wanted to use a shape that packed perfectly efficiently, we’d use some kind of cuboid... But we don’t see many cubes on shelves. Let's look at cylinders now...
The only real reason the article gives against using cuboids is that "the edges would be stress points", but it goes on to imply that this is mostly solved with "filleted (rounded) edges to reduce stress concentrations and to make them easier to manufacture."
I enjoyed the rest of the article relating to the optimal dimensions of the cylinder, but I still don't really understand why more products don't use cuboids (with or without filleted edges). Surely the space savings for shipping and shelving would be pretty significant, no?
While in school I spent 7 months in a co-op for a company that manufactured steel food cans. Although at the time I never challenged the need for circular cans I can say that manufacturing would be much more challenged for cube cans.
Metal likes to be formed by rolling, and it's relatively easy to image how cans are cut to length, passed through a die and seam welded. Obviously that's a lot of capital for one can size so round dies are easily swapped for various size cans on the same line. Forming stamped and bent edges would be much more intensive for changeovers.
Lids would require directional placement:
Round shapes fit in all directions, pretty clear here that any other shape would require it to be directionally correct.
Can liners are sprayed:
The inside of your cans are coated to protect the food, corners are harder to maintain an even sprayed coating
There are plenty of others I'm sure and this is a rambling post but maybe it gives a little more insight into the world of cans.
It sounds like a lot of this just comes down to the fact that our processes used for producing cylindrical cans aren't optimized for cuboids, and I won't argue with that.
However, part of me thinks that given some time and ingenuity, we'd come up with techniques that are better suited for the efficient production of cuboids. In other words, most of the things you mention are conceivably solvable by the right tooling (i.e. fixed costs). If that were the case, I'd have a hard time believing that marginal/per-unit costs would be significantly higher, and I think it would be interesting to look at the savings in shelf and transportation space compared to any of those increased production costs.
Cuboids can surely be done, he isn't arguing that. He's just observing all the ways in which cylinders are a very "elegant" solution, with a natural fit to metalworking.
I think metalworking has to be the key point of efficiency, because anything that comes packaged in cardboard (cereal, crackers, cake mix, powdered detergent, etc.) is a rectangle.
I would guess that cardboard is less expensive to source and work, so they can afford to take the extra effort to make it a box.
Cardboard's probably easier to form into rectangular shapes than cylinders - if you look at the way cardboard boxes are constructed, the joins are all done by overlapping which doesn't work so well on curved edges.
"Or as we say, Recycling is Bullshit."
This article is poorly written and filled with a lot of half truths.
One argument against glass bottles is that it takes a lot more energy to create them than for instance creating a container like tetra pak.
I'm not sure what their motives are, but articles like that scares me.
You can put stuff in recycling and they will take it (where I live in Northern California) and then sort it out to landfill at the processing facility.
> I enjoyed the rest of the article relating to the optimal dimensions of the cylinder, but I still don't really understand why more products don't use cuboids (with or without filleted edges).
Plenty do, when they are small enough that they can have sufficient strength and still have a pull-top opening (lots of sardine/anchovy cans are this way.) When they are bigger, they don't, because can openers.
Though I'm starting to see more "canned" vegetables/etc. that use lined cardboard cuboids rather than metal cans, so there's that.
The trade off, besides the stress points, is that a can opener would not be as efficient. That is mentioned when the author moves on to the cylinder. Furthermore, not mentioned in the article, a cylinder will support much more weight than a cuboid, making a cuboid more susceptible to smashing under load.
It's not all about space saving. You can get soup in cuboid packs, but I don't think it keeps as well, plus it's only good for smooth-textured soups that you can pour. If you have any kind of chunky or textured soup (which lots of people like), then opening it means unfolding/cutting the whole top of the container, which has a higher risk of spillage and requires more hand strength (for a kitchen scissors vs. a can opener). You do see it more commonly for things like chicken stock or other 'base' ingredients for cooking at scale.
Space saving matters a lot during shipping, on shelves not so much. The first job I ever had was stacking shelves in a supermarket as a teenager and I was so bored I would pass the time by calculating the volumes that fit on palette, on display and so on :) 25 years later not much has changed - most supermarkets still stack products 2 high and 2 deep or 1 high and 3 deep (depending on how stackable the product is), not least to limit the potential for mess. Smaller volumes usually have higher margins, so what's economically efficient for the supermarket isn't necessarily what's efficient in terms of volume.
Maybe because cuboids are harder to open with a can opener? All the cuboid cans I've seen have tabs on top and thus don't require can openers. It's conceivable that tab-opened cans are more expensive, don't preserve food as well, or something like that.
Sure, but it still requires the same kind of prescored lid; even with a key, I don't think that general design approach scales up very far while still not being too much of a hassle for consumers to bother with if there are competing products that are more convenient to open.
Random orientation is the key, "pretty good kinda aligned face out" is very fast and cheap both WRT labor and capital, and label alignment on the can is not a cost at all.
On cuboids the label alignment is beyond critical (even just randomly off center 1/4 inch on the shelf would look awful) and the capital cost to align the cubioids perfectly in their box and on the shelf are expensive.
(edited to add, I'm not saying our economic system would collapse if the cost of cuboid soup cans went up three cents a piece, but it would be an incredibly difficult corporate sell to convince one mfgr of many that he should accept a 1/3 of a million dollar loss compared to his round competitors on ten million units sold just to make them cube-ish, for, uh, fun)
Also wear in the box. Cuboids would tend to wear off entire faces of the label while being tossed around the warehouse but cylinders at worst will end up with a vertical streak.
Finally having worked retail as a starving student a quarter century ago there is a huge installed base of semi-standardized grocery store shelving that was never designed for the peculiar spacing cubiods would require. Or rephrased, cylindrical cans and rectangular prism boxes have evolved over decades to fit certain semi-standard discrete shelf configurations... If you want it on an American supermarket shelf, then a grid pattern of X by Y (preferably one shipping crate) will take up a certain discrete space. Not a quarter inch too big necessitating reconfiguration of the whole section, etc.
Who says they'd be randomly oriented? When I see examples of cuboid products on shelves (think boxes), they're usually stacked quite neatly and efficiently.
The only real reason the article gives against using cuboids is that "the edges would be stress points", but it goes on to imply that this is mostly solved with "filleted (rounded) edges to reduce stress concentrations and to make them easier to manufacture."
I enjoyed the rest of the article relating to the optimal dimensions of the cylinder, but I still don't really understand why more products don't use cuboids (with or without filleted edges). Surely the space savings for shipping and shelving would be pretty significant, no?