Five-axis machining secrets

5-axis machining defined
When manufacturers think of 5-axis machining, what most often comes to mind is 5-axis simultaneous machining, which means that all 5 axes are engaged at the same time to perform complex machining of such parts as turbine blades, impellers and aerospace airframes. Machining these kinds of parts requires all 5 axes (3 linear and 2 rotary) to move at the same time during the cutting process to achieve the desired geometry. Another form of 5-axis machining is 3+2, or 5-axis positional machining. In this type of 5-axis machining, one or more of the X, Y & Z axes move simultaneously, while the remaining two axes are indexed into position and do not move during that segment of the machining program. In 3+2 machining the NC program rotates one or two rotary axes into position and locks them in place while the X, Y & Z axes perform the cutting necessary to achieve the desired geometry. Typical applications for 3+2 machining include aerospace manifolds, and multi-sided and compound angle holes.

Types of 5-axis CNC machines
There are three basic types of 5-axis machines: types of 5-axis machines: (1) table; (2) head/table; (3) head/head. Vertical and horizontal milling-based machines are available in all three configurations, while vertical and horizontal turning-based machining centres use only the head/table concept.

Programming 5-axis machines
Manufacturers who are new to 5-axis machining sometimes express concerns about the complexity of programming and how difficult it may be for their machine operators to learn. They also worry about costly crashes if the programming is not performed correctly. Most users of 5-axis machines use CAM software for programming. Used with a high-quality machine, operating system, spindle and rotary table, a good CAM system helps insure optimum cycle time, excel?lent part finish and overall quality. The most efficient way to approach a part for 5-axis machining is to break down the processes into 3+2, 4+1 and then 5-axis simultaneous toolpaths. All 5-axis machines are most rigid when the rotary axes are locked in place, which allows for Maximum Metal Removal (MMR). The Okuma 5-axis machines sold and supported by Gosiger work with all CAM systems, including industry leaders Mastercam and Esprit.

Crashes can be costly, both in terms of damage to parts and equipment, and, of course, lost produc-tion time. Obviously, with five axes in motion, the opportunity for such incidents increases. The good news is that 5-axis machines equipped with Okuma's Collision Avoidance System (CAS) take the worry out of machine crashes, and significantly reduce set-up time. By entering 3-D model data for the workpiece, tool, chuck, fixture, headstock, turret and tailstock into the THINC?-OSP controller, machine operators can view a real-time simulation just ahead of the actual machine movements. This allows them to check for any interference or possibility of collision, and imme-diately stop the machine's
movement prior to a crash.

Does 5-axis machining make sense for your operation?
Although less than 5% of machined parts require 5-axis simultaneous machining, over 60% of parts are machined on 5 sides, which means they are all excellent candidates for 5-axis machining, or what Gosiger and Okuma refer to as "Universal Machining." We're all looking for ways to make parts and products faster and better at a lower cost, and 5-axis machin?ing of multisided parts does just that. The result is improved productivity and profitability. So here are a number of reasons why Universal Machining with a 5-axis machine is a sound financial decision:

Reduced Operator Time Per Part: Using 3-axis CNC machines for multi-sided parts typicZoom Kobe XII ZK12