12/11/15 New Workholding Devices Enable 4th Axis Machining

Shuttle Aerospace recently implemented 4th axis machining across all its pre-existing 3-axis vertical mills by creatively utilizing new workholding devices. This produced several challenges. The tooling required had to bemore compact and efficient to allow for the lessened work envelope created by the 4th axis and tailstock. It also had to rotate at high speed and be able to handle the different forces created by moving in 4-axis. “We needed a workholding solution that would hold parts of varying size, shape and material,” said Peyton Adair, Production Manager, Shuttle Aerospace. “As with most job shops, our profit is realized in production and can be increased by continuous time improvement.We needed something that would give us solid, rigid workholding and that was economical and easy to implement.” The company selected Pitbull and Uniforce clamps from Mitee-Bite Products LLC. “We have used the Pitbull clamp on several of these projects and have had great success,” said Adair. “In some instances, we have taken a pre-existing process, reworked the tooling and replaced Pitbull clamps with Uniforce clamping. With some minor programming changes, we have doubled the amount of parts the operator is loading and unloading every part run just by changing the clamping. These workholding devices are very easy to install, which makes creating tooling that much easier for the programmer and the operator.”

Shuttle Aerospace manufactures several aircraft components and assemblies that have to be loaded and unloaded quickly tomake schedule deadlines.According to Adair, the Mitee-Bite clamping that they utilize can be tightened and untightened with one turn of an Allen wrench, resulting in speedy part loading and unloading. “The clamping force provided is very strong,” said Adair. “To my knowledge, we have never pulled a part out of the Mitee-Bite clamping, and we consider it every time we plan a machining process.” The Pitbull clamp is a fixture clamp with positive down force and low profile gripping.According to Mitee-Bite, high vertical and horizontal clamping forces are generated due to the design of the Pitbull clamps. The clamps use a standard cap screw and are available in five sizes and several styles: a tool steel knife edge for aggressive stock removal; a tool steel blunt edge for general purpose; and a brass version to help prevent marring of the workpiece. Recently added is a machinable version for gripping diameters. Mitee-Bite’s Uniforce clamp features a compact design and enables the fixturing of more parts on the machine table. The steelwedge design spreads the clamping force uniformly on both sides of the 7075-T6 aluminum channel. It can be used for clamping flat or round workpieces. “Mitee-Bite is a great solution for our company because it is affordable, has a small footprint and is very easy to install,” said Adair. “We have seen gains in speed and efficiency on processes planned and implemented from the very first production run where Mitee-Bite clamping was used.” Shuttle Aerospace, founded in 1994 by owner Clovis Rebas, manufactures parts and assemblies for the aerospace industry. It specializes inmetallic and non-metallic machined components, aswell as all applicable types of heat treatment, surface finishing and welding. “Shuttle Aerospace strives to provide quality as well as on-time delivery at a competitive price,” said Adair. “We focus on serving our customers by making their needs our priorities. Our dedication to quality and customer satisfaction is reflected in and accomplished through our commitment to continual improvement.”

As seen in Manufacturing News www.mfgnewsweb.com