IfA Machine Shops Build Telescope Instruments

Scientific Instrument Technician Louis Robertson roughs out the cold structure interface for NSFCam2.
Photo by Randall Chung.

"We're one of just a few organizations in the world that does this type of work," says Randall Chung, scientific instrument technician and head of the IfA Scientific Instrument Shop. The instruments that go on the big telescopes on Mauna Kea and elsewhere are usually one of a kind, so they must be created from scratch. The IfA has the ability to design, fabricate, and test an instrument, and then to assist with "commissioning" it on the telescope for which it was designed.

Actually, the IfA has two "machine shops," as they are usually called, one in Manoa, and since 2001, another one in Hilo. Since the late 1960s, the Manoa shop has built instruments for the UH 2.2-meter telescope, the NASA Infrared Telescope Facility (IRTF), the Gemini North Telescope, and Subaru Telescope on Mauna Kea, the AEOS (Advanced Electro Optical System) Telescope Facility and Mees Solar Observatory on Haleakala, and the Gemini South Telescope in Chile.

Each shop is over 5,000 square feet, and the equipment in the two shops is similar yet complementary. They both have a variety of machines used to shape metal, as well as clean rooms where instruments are assembled and tested. To lift heavy objects, each shop has a forklift truck and a bridge crane.

The staff at Manoa consists of mechanical engineers Kent Fletcher, Vern Stahlberger, and Tim Bond, scientific instrument technicians Randall Chung, Louis Robertson, and Paul Toyama, and shop assistant Robert Godfrey. A machinist will join Richard Shelton, the scientific technician in Hilo, shortly. Mechanical engineer Alan Ryan also works in Hilo.

As the size of the telescopes has increased, so has the size of the instruments. One of the biggest instruments that the Manoa shop has designed and constructed is the sophisticated optical/infrared echelle spectrograph for the 3.67-meter AEOS telescope operated by the Air Force on Haleakala. The optical part of this instrument is the size of a small car. The Manoa shop has also built most of the instruments for the UH 2.2-meter telescope and the NASA IRTF. Those for the latter include NSFCam (a 1-5 micron camera) and CSHELL (a high-resolution spectrograph). A new, improved camera, NSFCam2, is in the final testing stages.

Because of its location, the Hilo shop can work on instruments belonging to telescopes on Mauna Kea without shipping them back to Honolulu for repairs. Its projects have included the UH8K Wide Field Imager (WFI) optical camera, and the design and construction of the Ultra Low Background Camera (ULBCam) for the UH 2.2-meter telescope. ULBCam uses new detectors developed at IfA Hilo for NASA's James Webb Space Telescope (see Na Kilo Hoku no. 10). These detectors are also being used in WIRCAM, a wide-field infrared camera recently commissioned on the Canada-France-Hawaii Telescope and NSFCam2.

http://www.ifa.hawaii.edu/instr-shop/