Seeing Coffee County Central High School’s new 3-D printer build parts from thermoplastic ABS filament, down to 100 microns, is almost like watching something out of science fiction.
But rather than working in the realm of speculation, the students in Jeff Hinshaw’s principles of manufacturing class are leading the cutting edge of manufacturing technology. It’s a technology so advanced that aside from still being in the experimental stage, it hasn’t even reached at least one area industry.
“We were at a workforce meeting and the CEO [of an area industry] said that he had one coming,” CHS CTE director Richard Skipper said. “He told me, ‘I’ve got one coming – don’t know who’s going to run it and nothing about it.’”
To showcase the capabilities of the MakerBot Replicator 2X Experimental 3-D Printer – funded through Manchester Area Chamber of Commerce Education and Workforce Development committee – the CHS administration recently invited area, state and industry leaders to the school.
But it was the students who were doing the talking. What fears they held didn’t show when talking to officials like County Mayor David Pennington, several Manchester aldermen and county commissioners and school board members, State Representative Judd Matheny and an even an aid to U.S. Congressman Diane Black.
“I was trying to figure out this part that I was making,” manufacturing student Matthew Watts told the assembly. “I looked it up on an online tutorials … figured out what was going on and got it to work.”
The excitement the students have for what they are learning is evident.
“I’ll tell you one thing,” Watts continued, “since we’ve got the [printer], it has hardly gotten any rest. I’ll come in for second period and the first words out of [Hinshaw’s] mouth are ‘run it.’
“These guys here,” referring to his fellow students, “are great guys who all know what they are doing. They’ve all gone in and done their fair share, all gotten burned on the 230 degree Celsius extruder – that hurts – and all have made whatever they could think of.”
A revolution in the
classroom as well as the shop
CHS Principal Joey Vaughn remarked that the goal of the school is to find where every kid belongs.
“These guys know they’re doing something that I cannot. And I’m glad you’re doing that because it’s needed.”
He described the Career and Technical Education (CTE) program as bringing in something that prepares students for life.
“You take a kid into a factory and show him the difference a millimeter can make – that’s math.” Vaughn said.
“You talk about real world, problem solving activities; that’s what they’re doing.”
Manufacturing student Aaron Pettit described it as nothing less than revolutionary.
“We’re always on the move and coming up with new ideas. That [innovation] will change that the world as well as how people our age build computer skills, and I’m happy to be here and a part of it.”
For the students, the 3-D printer is more than a high-tech toy, it requires the use of inductive reasoning, problem solving skills and troubleshooting activities along side practical computer aided drafting techniques, programming and higher order spatial reasoning.
Or to put it simply, the students see an object they need to build in their heads and must solve how to input the design into the computer using the computer tools and terms consistent with those used in industry.
The 3-D printer works as an additive manufacturing. Plastic from rolls is melted and injected in thin layers to form the product.
Think of the way a CAT scan makes thin “slices” of a patient to render a three dimensional image. Reverse the process so that the printer stacks molten plastic to form a real object.
Watts explained that an object is first designed using a drafting program like AutoCAD.
“You go in and draw the part you want to make, and save it as a .STL file.”
MakerBot’s program MakerWARE comes in to nail down the final touches like scaling the part, moving it around or which extruder prints the project.
“When you’re done with that, simply press make, and it sends it to the ’Bot.”
It sounds easy, but with all new technology, patience and trial and error come into play.
Hinshaw described an early project that didn’t go as planned.
Unlike traditional manufacturing methods that remove material to form a part, the additive method can produce finished items rather than just parts that must be assembled.
For the demonstration the class printed a working C-clamp as one piece. The finished project was a working tool without the casting, threading and milling that is normally used to make a clamp.
The printer can make seemingly impossible moving parts utilizing a complex series of gaps and supports.
“It’s a little hard to wrap your head around,” Watts admits, “but the threads are actually made inside of the body of the clamp.”
He explained that grooves for the threads are built with gaps left open and the supports that allow for the plastic to be built over the groove. The supports are cut away and discarded.
“You trim away a little and it starts moving. When you start chipping away at this plastic you start to understand how this thing works,” Hinshaw added.
“We’re smart and we’re good but the software does a lot of the work. It looks and sees ‘oh, that is going to print and fall off, so I need to put something under it.’”
Hinshaw said that the software slices the three dimensional rendering into thousands of slices and prints each slice one thousandth of an inch at a time.
It’s an introduction into some pretty hardworking software applications. The students collaborate with other designers in a virtual design community, MakerBot Thingiverse.
“The community is pretty small. This stuff’s been around awhile, but the way it’s being used, it’s on a such small scale this may be in homes in just a few years.”
Working in medium
other than plastic
If the project needs to be aluminum, the class can use the printer to make a casting for a mold to use in the foundry that Hinshaw developed for class last year.
Watts explained, “We can make parts and models that we need. There’s a process called sand casting. Say there’s a part that we need to make. Normally we would have to make it out of wood, make a mold out of sand, and pour aluminum that we melted into it.”
The only limit is that of the student’s imagination.
Senior Cheyenne Doty, one of the upper-level class’ two female students, said that the goal is sometimes not to make a part but to develop the skills needed to produce one.
“Some of the things we make are just because we want to see what different things look like,” she said.
“We are making the gears and other parts that we can make on the 3-D Printer for another 3-D Printer.”
Director of Schools Dr. LaDonna McFall said, “We are always looking to make our education more relevant and something that can lead our students into professions, colleges, careers or whatever they my choose to do.”
She lauded the help the chamber and local industry continues to provide to the system.
“[The Chamber’s workforce development committee] has been vital to put together these partnerships and the benefactors are the children and the community.”
As director of CTE, Skipper has acted as a liaison in the partnership.
“We are proud of our kids and … the things that are being accomplished,” Skipper said.
They said building relationships with the chamber and industry through the Coffee County Industrial Board offers solutions to some of the struggles that the system faces.
“When I took over as director, I went to all my teachers and said I would try to scrounge all the money I could,” said Skipper.
He asked the teachers for a want list of things that would take the school above and beyond. About the time Skipper and Hinshaw were discussing 3-D printers that were out of reach for the school’s budget, the chamber toured the school. Chamber past president Bill Nickels saw the opportunity to help.
Technology, Skipper added, is a way to involve students in learning.
“That’s how kids have proved that they can do things. Sometimes it’s more than we think they can handle.”