That break easily? These things are nigh indestructible in my experience. It’s possible that you had ones that weren’t rated for the appropriate weight, they have slightly different sizes and larger ones are beefier.
It isn’t even the plastic I have a problem with: this particular design had always been incredibly unstable especially if sitting down the slope backwards: the back legs would bend and you would fall over.
> These things are nigh indestructible in my experience.
Not in my experience. When new the plastic has enough flex to tolerate some abuse, but that doesn't last very long - especially if exposed to UV. Polypropylene does not like being exposed to direct sunlight.
Most used examples I've encountered are brittle and break easily if not already cracked. They're disposable plastic garbage.
Fortunately, there is a new recycling process [1] that takes 1/7th the energy footprint of creating virgin polypropylene. I hate these for the disposability too, but if we can direct them away from water bodies and landfills into recycled polypropylene, then that’s a modest improvement.
You're right, they break down and get brittle quite rapidly in sunlight. Here in the Philippines they don't last long outdoors. They have a much longer life as indoor mass seating.
A lot of them are used outdoors in harsh climates where they’re exposed to the elements, making the plastic brittle. Used as intended, they should be indestructible.
I don't think standing on them is what they're designed for, that strains even the best built chairs. The interesting thing about this chair I think is its relative strength compared to the absolute dearth of materials used, not its absolute strength, in my opinion — it won't ever be a strong as a steel chair, sure, but that is not why these things are remarkable.
> I don't think standing on them is what they're designed for, that strains even the best built chairs.
My memories of monoblocs suggest that the problem is less that the chair can't take the strain of being stood on, and more that it can't take the strain of being climbed onto. They're not rigid bodies; getting on to one to stand up will shake the seat around like crazy.
From my experience, they can be stronger than a steel chair. The cheap ones at least.
I had many steel chairs break at the welds. Or have the legs bent. For example, if you balance on the back legs, both the steel and plastic chair may collapse, but the plastic chair will keep its shape afterwards, while the steel chair may stay bent or break.
Chairs are designed for someone to sit on, not stand on. When the first chair broke due to the extreme concentration of weight in one spot, that should have been a sign not to abuse the second chair in the same way.
Its a question of tolerances, if they break when someone stands on them they there is a decent chance they will break when you sit on them, or sit down too fast, or sit on them on uneven ground that distributes slightly too much weight to one leg, or they have been in the sun too long and have become brittle.
I'm a relatively tall guy and am wary sitting on these, standing on them would be certain failure. They are essentially cheap trash that will spend ~12 months looking like a chair and 500 years looking like a broken chair in a landfill.
If the legs broke it probably wasn't weight concentration but just embrittlement due to UV and weather exposure. In my experience that's how most of these chair break, at the legs not in the seat.
