Thread by @TubeTimeUS

ever wonder where these lone traffic cones come from? out of place; out of context, often with a stencil that doesn't match your city's public works department? 🧵

this cone has a buddy. they're different, but they perform the same function. who or what is TBC anyway?

despite the fact that most people treat traffic cones as shared property, they very much have owners!

TBC stands for The Barricade Company. they're in the san francisco bay area and they rent these things out to construction companies, municipalities, and really anyone who needs a bunch of traffic cones temporarily.

now because most people still treat the cones as shared property, i really wonder how many of them actually get returned. 😂

it turns out a very large number disappear! on the order of *every single cone they purchase every year* 🤯

so people steal them, run them over, and misuse them (instagram.com/conesonpoles/) but they're surprisingly complex devices!

they sure look simple. "just a hunk of plastic," you might say.

but they have datasheets!

this is a datasheet for probably the most common style of cone: 28 inches tall and weighing just over 7 pounds.

this company uses what appears to be a double-shot molding process with two different colors of PVC plastic. the bottom half is recycled PVC and the top half is not (you can dye recycled PVC black, but other colors don't really work out)

for visibility, the top half uses a fluorescent pigment, which absorbs UV and other invisible light and re-emits it as visible light with a particular color.

because it converts different wavelengths of light rather than simply reflecting it, the pigment can reflect more than 100% of the incident light of a particular color, making it appear really, really bright!

more details on that here: dayglo.com/company/fluore…

but within the traffic cone lurks even more complexity! see those two white bands? they're another tricky and fascinating material...

that material is reflective prismatic sheeting. it uses a specially embossed material with a reflective metallized layer to create a *retroreflector*

what it means is that light coming in gets reflected back out in the same direction. so the light from your car headlights bounces off this material and goes straight back to you.

more details in this really fun paper: rema.org.uk/pub/pdf/histor…

the shape of the cone itself is also quite important, in more ways than one. first, the center of mass and the width of the base are set up so the cone must tip to a pretty extreme angle before it falls over.

second, the traffic cone must handle--uhh not sure else how to put this--squishing. watch the video clip.

to handle this, the cone is made hollow. this saves on material costs too, but more importantly, it makes THIS possible. 😂

forgot to mention it before but there are some good statistics about traffic cone theft in this article.

inquirer.com/business/where…

you can find more information (including datasheets!) on traffic cones at JBC Safety Plastics. they also have some interesting videos and a fun photo gallery.
jbcsafetyplastic.com/Product/detail…

despite how remarkably interesting and ubiquitous traffic cones are, there's still no traffic cone emoji!

notice how i made it through this whole thread without mentioning a certain popular video player? 😂

hmm i also wound up with this nifty 3D model of a traffic cone. what should i do with it, hmm 🤔