When James Camden Engineering Ltd had an issue machining some complicated aerospace parts, the Warwick based sub-contractor conducted a comprehensive review of the CNC machine tool market and concluded that a Fanuc Robodrill from Coventry-based Fanuc UK (
www.fanuc.co.uk) offered the best combination of cost, performance, precision and technology for its application.
Tool-room machinist Jordan Coles said: “We looked at many machines from a number of suppliers, but it was the Fanuc sales engineer, Nigel House, who was most focused on our needs.
“He looked at our components, the type of regular work we undertake and the quantities we produce. He then recommended the high-power version of the Robodrill D21MiA5 three-axis machining centre.
“There is often a perception — like the one we had — that VMCs are aimed at higher-volume production, and that Fanuc is a premium brand with a higher price tag, but Mr House delivered a solution that would also accommodate our small-batch and prototype manufacturing requirements.
“Indeed, we didn’t buy this machine solely for production machining, but also for machining small batches of extremely accurate parts.”
The company manufactures aerospace and motor-sport parts, and one particular job that led to the purchase of the Robodrill was a titanium aerospace job, which is 3-D printed via the DMLS method.
“This part required an unusual thread that would be best produced by thread milling; this operation was subsequently undertaken with ease on the Robodrill.
To simplify the machining process, James Camden Engineering asked for modifications to the ‘printed’ parts. Mr Coles says: “The 3-D printing of critical features isn’t quite as precise as we achieve machining on the Robodrill, which is why we finish all the critical features on our machining centre.
"To help with the machining process, we asked our 3-D print vendor to print parts on a platform with a reference block that is relevant to the machine tool platform and the orientation of the parts.
“When we load a part, we use the Robodrill’s Marposs laser-type tool-setting probe to determine its exact position, thereby ensuring that we can finish our parts with exceptional levels of precision based on this reference point.”
The accuracy ensured by spindle probing is complemented by the Robodrill’s performance — a bi-directional axis positioning accuracy better than 0.006mm with a repeatability better than 0.004mm.
“This is credit to the latest AC servo motors, the high-precision thermal compensation system provided by the Fanuc 31i-B5 CNC, and the substantial machine structure, which weighs more than 2,000kg. Ensuring high levels of productivity are a maximum feed rate of 30m/min and an 11kW 10,000rev/min spindle.
In conclusion, Mr Coles said: “From a service perspective, we couldn’t ask for more. The sales team were attentive to our needs and understood our business and our goals; and following the machine’s installation, Fanuc applications engineers frequently call in to check on us and the machine — and give us advice. This is far more than we had
expected.”