Adrian Bowyer makes an excellent point in this video. One of the more sensational objections to the spread of additive manufacturing technology is the fact that it can be used to print guns. However, CNC machine tools can be used to make guns, too, and they are actually better at it. The video above is part of a series of videos from the Science Museum debunking misconceptions about 3D printing.
Are you a machine shop that is considering getting into gear manufacturing as a new revenue stream, or has already purchased the necessary equipment to do so and wants to learn more? If so, Gear Production—the quarterly supplement to Modern Machine Shop—is for you. And you’ll also want to know about a valuable training opportunity that’s coming up soon. For nearly four decades engineers, technicians and others have gained an understanding of the mechanisms of gear noise generation, measurement and reduction by attending the Gear Dynamics and Gear Noise Short Course at The Ohio State University (OSU).
Beginning with the fundamentals of gearing, gear dynamics, noise analysis and measurements, the four-day course blends lectures with demonstrations, all powered by data compiled by OSU’s Gear and Power Transmission Research Laboratory. Attendees will learn why gears make noise, how the source can be identified, and methods for addressing gear noise challenges. Lecturers will also concentrate on gear system dynamics and acoustics, transmission error calculations and advanced signal processing. Real-world case studies will be presented, along with laboratory demonstrations and problem-solving exercises.
The course organizers are Dr. Donald Houser, professor emeritus of mechanical engineering at OSU and founder of the Gear Dynamics and Gear Noise Research Laboratory, and Dr. Rajendra Singh, director of the university’s Acoustics and Dynamics Laboratory. All gear manufacturers will benefit from attending, but especially those targeting automotive, aerospace, process machinery and wind energy markets. The event will be held September 28 through October 1, 2015, on the OSU campus in Columbus, Ohio. Learn more by visiting nvhgear.org.
Support structures are part of the engineering of an additive build. The support structure for this part accounted for half of the build time.
Let go of the notion of simply “printing” a part. That is, let go of the notion that you can just press a button and the part will be created—additive manufacturing is not like that. Instead, AM is a process with important process considerations all its own. Particularly where metal parts are concerned, these considerations need to be understood in order to realize the benefits that AM can deliver.
I recently spoke about this with AM researchers at Penn State University’s CIMP-3D facility. Find a detailed article at the link below. Here are important points worth knowing if you are considering AM for metal part production:
New design tools might be needed. Metal parts being made today were designed for casting, forging and/or machining. Additive manufacturing opens the way to complex, mathematically streamlined component forms that a CAD designer’s typical tools would not be able to create. Software for topology optimization becomes important.
There is still plenty of scrap. Support structures are part of the engineering of an additive build. These structures (see photo) consume not only a share of material, but also perhaps a large share of the cycle time for the part.
Orientation has an impact. Do you build a given part so that it lies on its side? Sticks up vertically? Leans at a 45-degree angle? This decision—how to orient the part for its AM build—has a significant effect on part accuracy, cycle time and where the support structure is needed.
Residual stress is the hidden challenge. Internal forces can deform an additive part as layers are added and the part cools. Sometimes, trial-and-error is needed to find the process for a given part that will overcome this effect.
Material changes with use. Some particles melt before others. As a result, powder left over from a build has slightly different particle distribution from the powder that began it, and thus different properties. AM powder changes over time to a much greater extent than other manufacturing material stock.
Your new lightweight metal might be titanium. Titanium alloys are well-understood in additive manufacturing and therefore easy to apply. This tends to make titanium the AM metal of choice. Indeed, because of its high strength-to-weight ratio, a part redesigned for weight savings through AM might be lighter in titanium than it was when it had been a thick, solid part in aluminum that was designed for a more conventional process.
Watch this video for a demo of the hand scraping process, and find a link below to a white paper on the topic.
Hand scraping of mating surfaces on a machine tool enables the surfaces to be flatter, more accurately aligned, longer wearing and freer to glide across one another. No automated or mechanical operation can match these benefits. Machine builder Okuma has issued a white paper detailing the benefits of hand scraping, at technique it applies to all of its machines.
The company contends that hand scraping maintains high levels of CNC machining accuracy and reduces wear and tear, resulting in a long, stable and productive life for the machine. This manual process ensures that tight tolerances are consistently maintained and that precision CNC machining performance is sustained for years, therefore yielding the lowest cost-per-part, the company says.
In a nutshell, the hand-scraping difference accounts for four main benefits.
Accuracy - Scraping is done to align components within millionths of an inch, allowing for consistently-held, tight tolerances.
Flatness - Contact points prevent rocking, add balance when tightening, and allow for true flatness in parts.
Oil Pockets - Oil on the surface allows gliding motion.
Appearance - The finishing touch of scraping is aesthetic. Parts are “design scraped” to achieve an attractive textured finish.
To download a copy of the white paper, click here.
Certain products succeed long enough that the product brand acquires its own cachet apart from the originating company name. In certain circles, Seco’s “Duratomic” is like that. The toughness and wear-resistance of this cutting tool coating have made it successful in steel machining applications such as the one portrayed in this video. When the coating was introduced in 2007, Seco says it represented the first time a coating had been manipulated on the atomic level. And in few days, the company says, Duratomic will be introduced again.
Launching April 1, a complete overhaul to the Duratomic line will improve upon the previous successful coating with new coating technology delivering 20 percent greater life across most of the tool’s applications, including heavy, low-speed turning applications that are commonplace among oilfield manufacturers that have applied this tooling in growing numbers in recent years.
Another important feature to be introduced is “edge intelligence,” the company says. The dark color of Duratomic inserts has made edge wear difficult to see. This has been a challenge in high-volume facilities that change inserts frequently, because inserts with unused edges sometimes get discarded. The new Duratomic addresses this challenge with a multilayer system that the company says makes tool wear easy to visually gage.
Learn more by visiting the Duratomic site, which includes a countdown clock ticking the moments until the line’s relaunch.