Not Necessarily The News In Hoke

By Ken MacDonald

In our last episode of “We Do Science So You Don’t Have To,” we tested whether it’s less bumpy to cross the railroad tracks on Harris Avenue at normal speed or annoyingly slow down to a crawl like most Hoke Countians, and, using a seismograph iPhone app, determined it’s better to not drink coffee while conducting the tests. And, yes, to cross at normal speed.
In the episode before that, we used a handheld GPS receiver with Wide Area Augmentation capabilities, which provides accuracy to three meters on average, to find out exactly how far we’re being asked to drive behind local garbage trucks, which at the time had signs that read, “Keep back 500 feet,” and discovered that’s about as far as from The News-Journal to the police station, and that you can’t read the sign from that far.

Today, in our continuing series we find that 3-D printing is not made up, even though nobody believes it’s real.
Yes, we know it’s been nagging you ever since you heard about 3-D printing. Can a printer attached to a computer really print an object, such as a crescent wrench that can actually be used to tighten a nut? The video on YouTube shows it, but video and photos can be faked. Just like the Apollo 11 lunar landing, which we all—or at least 20% of us, according to surveys—know was faked with Photoshop in a warehouse in Roswell, New Mexico. Or perhaps 3-D prints are being imitated, like certain appendages of certain celebrities.
Inquiring minds want to know. So to find out, we first created a small airplane in a 3-D drawing program, Google Sketchup, which has the learning curve of romance but is free, and since we lack the research budget of a government, were stuck with it.
Noble as we are in the aid of science, the project also had the goal of replacing a crude prototype of the plane, which had been flying on the antenna of a pickup truck for six or seven years. The first model was made of a Sprite can fashioned into the plane, stapled together and drilled through the center so it would rise up on the antenna of the truck when it reached an airspeed of about 25 miles per hour. After metal fatigue set in from years of flying through all sorts of weather and enduring Raeford’s thousand-percent summer humidity, we created a second version, made from a printing plate. It too flew for several years but was beginning to look nasty and all whompyjawed.
Enter 3-D printing.
If we could design the plane in a 3-D program, we could upload the file to a company with a 3-D printer, pay them a handsome sum, wait two weeks, and get back a plastic version of what we’d seen on the computer screen. Their printer’s head would move across a bed of plastic powder, squirting microscopic drops of resin onto each bit of powder until, with thousands of passes, the object would be formed a tiny layer at a time.

It's real: on the computer screen, out of the box

Conclusion: it’s real. What began as a computer file arrived in a box Friday. (It cost $46. A stainless steel version was offered for only $230.) After two coats of acrylic paint, a hole drilled through its center and its ugly tail hack sawed off, the plane flew its maiden voyage Saturday, lifting off at exactly 25 m.p.h. It’s durability will be determined in a few years. Or maybe days. Depending on its…um… durability.
Anyway, in our next episode we’ll use an inclinometer to determine which is the best sledding hill in Hoke County, should it ever snow.
In the meantime, send your local science questions to The News-Journal, because “We Do Science So You Don’t Have To.”®