3D printers may be as commonplace as home computers

Growers and manufacturers alike have dreamed of the day when, instead of sending away for a part, they could quickly and easily test and make one themselves.

That dream is closer than ever to becoming a reality, as the science and art of 3D printing grows in scope and popularity. The technology enables individuals and companies to print customized components on-site, with an ever-increasing variety of properties and functions.

“I have yet to meet an industry that can’t be helped by 3D printing,” said Mike Nagel, business technology manager for Advanced Technology Systems, during a presentation at this year’s Produce Marketing Association (PMA) Tech Knowledge symposium. Nagel has worked with a number of industries, including food processing and agriculture, in implementing 3D printing systems.

3D printing is already being used to make objects such as human organs, prostheses, construction forms and vehicle parts. More than 1,000 parts on the latest Airbus jet are 3D-printed.

The foundation of 3D printing comes from a different way of looking at manufacturing, Nagel said. The traditional method is called subtractive, where a large piece of raw material is reduced, molded and shaped into the desired end product. In the art world, a sculptor is the primary practitioner of subtractive manufacturing.

“By comparison, additive, or 3D, takes what you design and prints only what you need,” Nagel said.

Traditional manufacturing can mean dealing with long lead times, expensive tooling and design limitations, and is often more suited to high volumes of products, Nagel said. The advent of 3D printing technology enables a quicker reaction, the ability to print only the parts that are needed and the ability to test and discard at a minimal risk. This type of manufacturing is better suited to customization and a low volume of products.

There are a variety of technologies used in 3D printing, but perhaps the best way to grasp the technology is to think of how icing is added to a cake. The printer, working from a pre-programmed, computer-aided design (CAD), applies the desired material in layers to create the end product.

Two of the major printing technologies are polyjetting and fused deposition modeling, or FDM. Polyjetting is similar to traditional two-dimensional printing, starting with raw liquid fed through a dry bed that ejects the material onto a surface in layers. Ultraviolet light is used to adhere the printing material to the desired surface. FDM is the older technology. It feeds a plastic filament of the desired material through a drive motor. The material is then heated and extruded, also layer by layer.

The printers range in size and complexity, and are used by home hobbyists (who have gathered into online communities of enthusiasts at websites such as thingiverse.com) to major manufacturers.

“In our shop, we have products as small as a traditional two-dimensional desktop paper printer all the way up to systems that are 8,000 pounds and as big as a large SUV, and then everything in between,” Nagel said.

Agriculture is also exploring the benefits of 3D printed parts and materials. Nagel and Advanced Technology Systems have worked with farm machine companies to print components such as combine attachments and custom seed applicators. On a smaller scale, the website FoodRising.org offers free 3D printing software to make items such as valves, clamps and fittings.

The machinery company conventionally makes its machine attachments by rotational molding, which was not capable of achieving all of the desired geometries and shapes. 3D printing allowed the company to inexpensively produce prototype attachments for a 12-head combine, and test their effectiveness in a variety of field conditions.

“This isn’t something they will make millions of,” Nagel said. “3D printing reduces their risk and allows hem to try something new and to try different shapes and sizes.”

Other types of food manufacturing are seeing increased use of 3D printing. They include:

• Bottling: A bottling line that needs frequent changeovers in container sizes, and the accompanying changes in tooling, can benefit from 3D printing technology to accommodate a wider variety of bottle sizes.
• Breakfast foods: Cereal makers are using 3D printing to make dies for new extrusions and novel shapes for cereal – by extension, this same concept could apply to unique cuts of produce and other types of foods.
• Packaging: As package shapes and sizes change with more frequency, and more unique shapes are desired, 3D printing is being used to produce the molds used for these new styles.
• Retail: Store fixtures and point of purchase displays increasingly are being produced by 3D printing. This can be particularly important when testing the dimension of items that need to maximize the efficiency of available shelf space.

The future of 3D printing promises wider use of the technology and the ability to print more types of objects. Printers can already make one object with up to 70 different physical properties — far more than would ever be needed, Nagel said.

Printers should also be more widely available.

“At first, larger companies would buy a lot of 3D printers and put them in one location. All the engineers would send files to a central hub and the hub would print out all the parts and ship them back to the people who designed them. They thought that was the ultra-efficient wave of the future. Now it’s the opposite. The benefit of 3D printing is to have it close to you, and that’s what companies are doing. They will try new things more often and use them in the way they want to use them.”

Technical skill and expertise is required to make the designs that the printers use, which will come from people with training in CAD. Some level of skill is also needed to scan the designs into the printer. However, one day is all that’s necessary to train someone to operate a printer, Nagel said.

“If you come to our shop in St. Paul, Minnesota, you will see 15 different types of printers, and one person can operate them all,” Nagel said. “The key to this technology and the major benefit to it is that it’s very simple to operate.”

This ease of operation should also fuel the proliferation of 3D printers for personal in-home use. Simple printers are available for as little as $500, and their numbers could grow in a way similar to how home computers have expanded.

As with other technologies, expect to see advances in the capabilities of 3D printing. In the future, all someone might need to do is scan an image of an object in order to begin the work of printing it. Methods other than layering, such as creating finished objects from a pool of raw material, may also arise.

And then there’s the question Nagel is always asked: Can food be printed? Could there come a day when we can push a button and get a crisp, juicy Honeycrisp apple or an heirloom-quality tomato?

The answer: We’re already “printing” food, if the concept can be applied to cupcakes and snacks such as Twinkies. The base material — the dough — is shaped and formed and then icing and frosting are layered on the top. But the biggest obstacle to printing food from base ingredients is the issue many other foods have: Will it taste good? That may be the reason why one of the most common foods now undergoing experimentation for 3D printing is chocolate.

— By Lee Dean, editorial director