Greg comments on his difficulties with the stiff consistency of the cornstarch / caulk mixture, which seems like a germane time to mention a comment on last night’s Oogoo post from W. Aaron Waychoff, who claims to have had success using glycerine as an additive instead of cornstarch. [Thanks, Greg, and Aaron!]
Turns out, though, that mixing in some cornstarch accelerates the drying process; just how much depends on how much starch you add. The author recommends starting with a 1:1 mix. I’m not sure about his explanation that the process works because the hygroscopic starch carries moisture into the internal volume of the silicone, but in any case there are probably other additives that will accelerate the process as well as or better than cornstarch. You might even find one that’s not opaque and allows for translucent castings.
“In High School Chem Labs, Every Cameraphone Can Be a Spectrometer” on Wired.com. [via adafruit] University of Illinois chemistry professor Alexander Scheeline has developed software that turns a camera phone, an LED, and a few other cheap tools into a spectrometer. Armed with these, he thinks we can bring high-end analytic tools to high school […]
MAKE pal Steve Cooley, who manufactures the Beatseqr hardware performance controller, has posted the lab notes from his recent experiments with various silicone products for casting monolithic soft button arrays. I love it when people do this–the steps and missteps that happen along the way are often as interesting, and as helpful, as the finished product.
I was thoroughly entertained by this bit of hobby chemical sleuthing from Michael August Pusateri, who observed years ago, while bored on-shift, that the hot sauce at the fast food joint where he was working would clean the oxide off a penny. My immediate assumption–that the effect is due to vinegar or some other acid in the sauce–turns out to be only half right. The right answer, and the process by which Michael arrived at and verified it, make for interesting reading. You might even find a use for it.
I love this Helix Chemica scanned from a 1944 edition of Hackh’s Chemical Dictionary. Besides the usual information about atomic structure and periodicity of properties, this variant on the familiar table displays the natural abundance of each element in living organisms, the sun, the sky, the ocean, and terrestrial and extraterrestrial rocks.
Spotted in the MAKE Flickr pool, this beautiful modular origami construction, Ã la Tomoko Fuse, from user fdecomite. Its formal title, Giant short nanotube, provides a rare opportunity to observe a double oxymoron in the wild.
