An Interview with Douglas Greenwood, Additive Manufacturing Lead, Advanced Technology IPT at Fleet Readiness Center – East

Doug ’s career in additive manufacturing began in 1990 when it was called rapid prototyping. He spent 6 years working for Laser Prototypes, Inc. as the SE regional representative and was then recruited to work at Square D/Schneider Electric in Raleigh. In 2001, he joined 3D Systems as an Applications Consultant supporting and training SLA & SLS customers. Doug took a position at Fleet Readiness Center East in 2008 and currently serves as the Additive Manufacturing Lead for the Advanced Technology IPT. Over the last 28 years, Doug has seen dramatic changes and advances, so we were eager to ask him a few questions.

What are some of the most notable changes that you have seen over the last 28 years?

The changes are dramatic. I used to work for Chuck Hull at 3D Systems which is the company he founded after he patented his StereoLithography Apparatus (SLA). I had just finished a Master’s program at NC State, and this meshed with the work I was doing in my thesis. At that time, the primary application was for the injection molding industry because designers could get a quick first look at what they designed before they cut steel. In other words, it gave you a way to make your mistakes early in the design cycle. Most of the CAD systems on the market in the early ‘90s were 2D or 3D wireframe. There just weren’t many solid modeling systems, and visualizing something based on 2D or 3D wireframe was hard to do. The ability to actually see what you were designing was amazing.

Since then, many 3D printing processes and materials have been developed and the industry has branched out into so many new and exciting areas. Now it is even possible to print human organs!

Tell me about the transition from civilian manufacturing to the Fleet Readiness Center.

This has been a learning experience.  I started work at Cherry Point working on helicopter drive systems in 2008. Cherry Point is one of 3 industrial FRC’s for NAVAIR. We are known as the vertical lift center of excellence. We do all of the depot level repairs for USN & USMC aircraft. If it takes off or lands vertically we support it, including helicopters, the F-35 JSF, the V-22 Osprey, and the AV-8B Harrier.

The complexity of the organizations within all the FRC’s and NAVAIR takes a while to understand and I am continually learning, even after 10+ years. There are many different stakeholders in the work FRC-E does to provide depot-level maintenance, repair and overhaul for our customers along with the engineering and logistical work to support the fleet aircraft in-service. In order for anyone to work effectively at FRC-E you have to understand or at least be aware of all these relationships in order to do your job. The purpose of the Advanced Technology team is to evaluate new technologies that have the potential to help us in the work we do at FRC-E, AM being one of them. Funding for new equipment can be challenging and we have to anticipate and work through those challenges on a regular basis.

But in my industry experience, when a 3D printer came into an organization, the elegant simplicity of AM was suddenly evident to everyone, even if they didn’t really understand what all the fuss was about. Their imaginations get fired up. They think of things that they wouldn’t have thought of before.

What are some of the top 3D printing applications that you have seen in the military?

We have 3 Stratasys FDM printers. We use the polycarbonate material to print form blocks and use them to form sheet metal into different shapes. All of the industrial FRC’s use FDM printers in their work. Metal powder bed and nylon powder bed technologies are also being used in other facilities but not yet at Cherry Point. We have many off-aircraft AM applications such as support equipment,  jigs and fixtures, and chem-mil templates, drill guides, form/fit models, visualization models, etc. and we use our FDM printers for all of these.

Beyond these conventional uses of AM there is a high level of interest in using AM materials and processes to make part substitutions for obsolete and hard to procure parts, not only in NAVAIR but throughout the DOD. There are many challenges to considering an AM part substitutions, not the least of which is that much of our engineering data is not in digital form. Many of our older aircraft platforms were designed completely by blueprint before the advent of CAD systems. So any digital design or manufacturing process has to begin with converting the 2D blueprints to 3D data.

One of the motivations driving the interest in AM part substitutions on-wing is that the supply base for many of our legacy platforms has shrunk, making spare parts harder to procure. The companies that used to make parts have either gone out of business, they have decided it’s no longer profitable to make the parts, the tooling has been scrapped, or any other of a host of reasons.  It then falls to depots such as FRC-E to be the manufacturers of last resort. As a result, we are a huge job shop. We have many thousands of components that we deal with, and when we have to manufacture something the quantities are very small. So it’s a tremendous challenge to corral all of the resources required for any given component. We also have to answer questions about airworthiness and flight criticality where there isn’t any room for compromise.  In other words, our efforts to use any AM process to make part substitutions, be they non-flight critical or flight critical, are proving to be challenging and we are working through all of the many aspects. Fortunately, the OEMs have done the work to put AM parts on their aircraft. Those AM solutions are slowly coming into the public domain, making them available for use by other organizations. Taking this information and applying it to FRC-E and NAVAIR aircraft will help as we move forward.

Where do you see this going over the next few years?

FRC-E’s AM applications are limited by the size of the largest printer we operate, all other things being equal. So we have some research going on with large format 3D printers. These systems print tooling shapes by melting and extruding pellets of thermoplastic material instead of the thermoplastic filament on our current machines. This makes it possible to extrude the material faster and over a larger area. We are looking at solutions ranging in size from 10’ x 10’ x 5’ and larger.  FRC-E applications for these printers are for sheet metal forming and layup of composite materials. Some of our OEM’s are using large format printers for their tooling applications as well. Other tooling applications are in the marine and wind turbine industries.

We are also looking at laser-based additive repair solutions that build up material onto that substrate and machine it to print. This process can restore worn surfaces on engine components.

Join us on February 28th in Kinston, NC to learn more about 3D printing technologies and use cases in the Department of Defense and to hear Doug in person.  Register today!