Why Was This Machine Chosen for Composites?
General Tool could not buy a major machine tool that would be solely dedicated to composites. That’s unrealistic—the Ohio contract manufacturer machines many types of parts for aerospace and other industries, with the mix of work always subject to change. However, it purchased its latest large five-axis machining center with the understanding that machining composite materials, notably carbon-fiber reinforced plastic (CFRP), might represent a large share of this machine’s work.
The machine the company chose was the Parpas Diamond 30 gantry-style machining center seen here. Why does General Tool expect that this metalcutting machine tool will also be effective for composites? These reasons:
- Large travels. This is a basic point, but important. Composite parts are generally complex, involving machining at various angles. Large travels allow for single-setup machining, as the spindle head moves and pivots all around the part.
- High ways. A U-shaped design places the way systems high above the work area. Coolant carrying dust from the composite machining won’t get into the ways.
- Thermal stability. This machine’s structure is cooled with refrigerated air. CFRP parts feature very low thermal expansion, so the machine should have something like the same dimensional stability.
- Probing. Other large machines running composites at General Tool are older, and don’t have this capability. Adding probing to the cycle will permit in-process inspection to assure the accuracy of expensive composite parts.
Read more about General Tool’s history and future in composites machining.
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