Sculpting with polyurethane foam

We're big fans of Flinn Scientific.

By we I mean the teachers of the summer teacher camps because Flinn cuts us a slight discount with our ordering for the camps, but I've been a Flinn fan for far longer than my involvement in the ASM program. Flinn is a company that provides outstanding service to teachers, offering free workshops on safety and teaching around the country as well as at NSTA and ACS conferences.

Ok, enough gushing, to the material science stuff.

The two-part foams that we use in our summer workshops actually comes from IASCO (the flexible foam is FF-5Q and the rigid foam is RF-4CFCQ in their catalog), but Flinn does sell the rigid foam as C0335.

The video above is neat because it shows the more artsy applications, turning the foam into cute creatures with the addition of googly eyes and pipe cleaners. I also like the giant tower of foam that's behind the presenter. Anybody wanna make me one of those?

Adjustable Density Expanding Foam

This may or may not be exactly the same expanding foam that we use in our ASM teacher summer camps, but that graphic up there (something I found in casually searching for 'expanding foam' images - as you do donchaknow) shows something that we've noticed and only casually researched. Adding more food coloring (which comes in water, natch) isn't always productive toward what you want to achieve. In fact, adding way too much food coloring can cause the unexpected effect of less expansion as the bubbles get too big to support the structure and weight of the foam.

Check out Public Missles Ltd's article detailing this effect on their foam. It's the second page of the pdf that describes the effect of adding more water to their foam and why you might want the different densities that result.

College Student Invents Building Material

It looks like Micah has taken down his blog - at least I can't find it via any of the search terms I could see at 1:39 in the video. He has, however, gone on to found Pulse Motors, an electric bicycle start-up - more about that here, here, and here.

It's always interesting in camp and in class to expand (see, I'm funny) on the uses of the expandable foam. There's the standard Great Stuff foam, expanding foam insulation, and Nerf, but what else is there to the foams?

Now there's making a building material out of them...in Pittsburgh, anyway.

Quick question, though, what's with the density currents above the container at 0:02 and again 4:55? Does the stuff cure faster with a heat gun treatment? Gotta try that sometime...