Modern Machine Shop

JUL 2018

Modern Machine Shop is focused on all aspects of metalworking technology - Providing the new product technologies; process solutions; supplier listings; business management; networking; and event information that companies need to be competitive.

Issue link:

Contents of this Issue


Page 89 of 147

MMS JULY 2018 88 WORLD'S L ARGEST DIGITAL CAMERA opportunity to improve our manufacturing process and get better at predicting and planning for future projects," says Shane Slack, director of manufacturing. One way this knowledge building plays out is in a new emphasis on running parts, even one-offs, unattended. "We like to challenge ourselves to run lights-out any time we can," Mr. Slack says. Keller's newest machining center, a DMC 160 five- axis model from DMG MORI, for instance routinely runs 60-plus hours unattended over weekends with success. Getting it right the first—and maybe only—time is critical. The planning and experi- ence it takes to do this and adjust when things go wrong have become especially important on the large parts needed for the LSST camera. ...To Look Forward Keller has had to draw on its knowledge of welding and stress relief as well as machining expertise in manufacturing the LSST camera parts. When I visited in early April, the company had already shipped the back flange and was in the midst of producing the camera housing. The back flange is a flat, cylindrical part that provides structural support for the rest of the camera and serves as the mechanical interface between the camera and telescope. Made from a 6061 aluminum forging, the part was subject to vibratory stress relief before any machining to stabilize the atoms in the metal. Then, Keller cut the various holes and pockets on its Parpas XS 63 five-axis gantry machining center. This machining center offers a large working envelope with X-, Y- and Z-axis travels measuring 236 by 118 by 59 inches, plenty of space to accom- modate the 1.65-meter-diameter flange and housing, the latter of which measures 30.435 inches tall. However, the real benefit to this machining center is its exchangeable heads. Keller has three options: a roughing straight milling head, a universal indexing right-angle head, and a universal five-axis high-speed milling head. For one-off and low-volume jobs, having these options provides the flexibility to perform a range of operations on the Parpas with a limited number of setups. For the f lange and housing, Keller used the high-speed head, which features an HSK 100 spindle interface and offers up to 20,000 rpm. The head's small size means that it can fit The LSST camera's back flange measures 1.65 meters in diameter and will serve as the interface between the camera and the rest of the telescope. Shrink-fit tooling plus a very light depth of cut enabled Keller to reduce vibration and improve accuracy in machining both the back flange and camera housing. Photo: Keller Technology

Articles in this issue

Links on this page

Archives of this issue

view archives of Modern Machine Shop - JUL 2018