December 17, 2014
How to Make a 3D-Printed Corn Sheller
contributor: Rob Goodier
Shelling corn by hand is hard, long and boring work, but in some parts of the rural developing world it is the only way to remove the kernels from the cobs.
If only everyone had a handy corn sheller. The problem is that commercial shellers are too expensive for most families and cheaper versions, if they’re available in a region at all, are one-size-fits-all. Corn comes in different sizes depending on the variety grown, soil, weather and other conditions and also on the season. A single-sized sheller might not be suitable year round, so customized versions could be useful.
The do-it-yourself corn sheller is a good option, and E4C has reported on a series of low-cost shellers that upcycle materials like tin cans and PVC pipe. But these can also be a chore to make.
3D printers have become increasingly accessible, and using these tools, my team and I at the Michigan Tech Open Sustainability Technology Lab have developed a solution to the corn sheller problem. This is how to 3D print a customizable corn sheller. It is an example of open-source appropriate technology (or OSAT for short).
By using a low-cost RepRap (self-replicating rapid prototyper) 3D printer, or a solar-powered version of the RepRap, anyone can easily print out the right corn sheller for their needs. This academic paper explains how 3-D printing could be a powerful tool for pulling people out of poverty in the developing world. Here we will look at how it can improve the simple corn sheller.
As the video shows, to shell corn by hand you have to crack the cob in half, pick out the first row and then strip off the rest of the kernels. But with a sheller it is much easier.
Testing with children in the U.S. showed that in general they could not shell the corn by hand because they could not get it started. However, the printed corn sheller makes it easy even for those under 5 years old to shell.
Joshua Pearce directs Michigan Tech’s Laboratory in Open Sustainability and Technology.