Yanderson Buonto, Somchai Samrerng, Mesin Tessema and Jose Corarrubias (from left) watch as Samrerng heats his Stirling engine for a speed test, Thursday, June 4, 2009, in the Shoreline Community College CNC machinist program area. (Click here for more photos)
Somchai Samrerng, a student in Shoreline Community College’s CNC Machinist program, knows how to turn up the heat on his fellow students, literally.
On Thursday, June 4, 2009, Samrerng won the friendly, but hotly contested Stirling engine competition. Conducted in the program’s on-campus machine shop, the competition was part of an open house hosted by instructor Keith Smith and other program officials.
“Somchai is in out three-quarter CNC machinist program and on track to graduate this spring,” Smith said.
It is an intensive program, preparing qualified students for entry-level machinists using CNC (computer numerical control) equipment. Basically, CNC machines are computer-controlled versions of the hand-operated versions. Students in the program learn programming and basic set up and operation of CNC machines, blueprint reading, shop mathematics, machine tool theory, inspection, surface plate techniques, and statistical process control.
For the contest, students built their own Stirling engines, machining all the parts except for some screws from scratch. Invented in 1816 as an alternative to the steam engine, a Stirling engine uses heat, converted into mechanical power by compressing and expanding a fixed quantity of air or other gas. They are often called “heat cycle engines.”
On Thursday, students used a propane torch to heat one end of their engines, causing a wheel to turn. An optical device akin to an automotive timing light was used to measure revolutions per minute of the wheel.
While the basic design of all the entries was the same, subtle changes in wheel design, fasteners and other aspects resulted in significant speed differences. Samrerng’s engine topped out at just over 1,300 RPM while other entries were in the 800-1,100 RPM range.
The CNC Machinist program is eligible for several types of financial assistance programs, including I-BEST and Opportunity Grants. A new program, aimed at working adults with classes on weekends, is scheduled to start Fall Quarter, 2009.
The program is also the focal point of a recently announced Bill & Melinda Gates Foundation grant in partnership with the National Association of Manufacturers and Shoreline Community College. SCC and the program will be one of four pilot projects across the country to integrate a standardized skills curriculum with a manufacturing program.