One concern a number of engineers have about additive manufacturing and 3D printing is the finishing process. How can this process be made simpler and easier? In the last year or two, a couple of hybrid machines that combine additive manufacturing and CNC machining have emerged in the market.

Some companies that provide prototyping and low-volume manufacturing, such as PTI Engineered Plastics in Macomb, MI, are adding these hybrid machines to their repertoire. PTI Engineered Plastics recently announced the addition of the Lumex Avance-25, from Matsurra.

The Lumex machine can manufacture complex molds and parts by direct metal laser sintering (DMLS) without the need for secondary finishing processes. This one machine will produce a finished surface on par with that of a conventional machined component in a single setup.

The metal layering/laser process repeats ten times until the thickness reaches 0.5 mm. Then, the LUMEX high-speed mills (CNC) and contours the shape to a precise finish. The ten layer metal sintering and CNC milling repeats until it constructs the entire mold, insert or part. Where the sintering process would leave a rough surface requiring post-processing, the LUMEX technology finishes surfaces to that of a conventional machined component in a single setup.

PTI will use the Lumex hybrid technology to grow high precision finished mold inserts. Some of the added benefits of the Lumex are: 3D conformal cooling channels which will shorten the cooling cycle reducing mold time in the press. Gas venting is another plus; the sintering can be precisely controlled, thus reducing gas traps. With the Lumex deep slots can be machined eliminating the need for EDM process.

Leslie Langnau
llangnau@wtwhmedia.com