Just as an “overnight success” is generally the result of years of effort, a “breakthrough” in part machining productivity usually is the sum of a number of carefully engineered individual improvements.
Zaytran, Inc. used several
improvements to reduce machining time from more than 45 minutes to less than 20
for a 6061 aluminum component that measured 6" x 5" x 2".
Zaytran, located in
Seeking to speed production, Jerry Williams, Zaytran process engineer, consulted with CGS.
As a solution, CGS produced special versions of its Ferocious 2-flute, 55* high-helix, solid carbide end mills by adding through-coolant capability. The designs allowed coolant flow through the 3/4" dia. and 1" dia. tools with flute lengths up to 5", to effectively push chips out of the cavity. “There was no other way to get coolant down where the tool was actually cutting,” said Steve Maxwell, Zaytran production team leader and programmer.
Zaytran was able to square the parts using just the CGS end mills, while other suppliers’ end mills, with profiling lengths of 3" to 4", were unsuccessful, thus causing Zaytran to have to apply face mills on two sides. Face milling proved unnecessary when applying CGS end mills in shrink-fit holders. “We could do profile milling, 3-1/2" or 4" deep, and maintain 0.001" or 0.0015" taper over the whole length of the part, eliminating the need for the face mills,” Maxwell said.
A large contributor to the decrease in machining time was the end mills’ capability to run at high speeds and feeds. The micro grain-carbide tools feature a circular land that facilitates maximum feed rates and cutting speeds, and the tool geometry is engineered to produce efficient sharing action and vertical chip ejection. Williams said the shop typically runs the end mills at feeds of 100 ipm or faster, in contrast to the 40-to-50 ipm feeds employed with previously used end mills.