Arm your machine tool with a portable CMM - Rapid Traverse

FARO Technologies (Lake Mary, Florida) is best known for its FaroArm portable, articulated-arm CMMs that are used to measure large parts, weldments, assemblies and other components that would be difficult or impossible to bring to a conventional CMM. Now the company has introduced a smaller "personal CMM" designed expressly for the machine shop. Called the FARO Gage, the measuring device has an articulating arm with a 24-inch reach that can reach all exposed features and surfaces of a part without having to be repositioned. A magnetic base allows the unit to be mounted right on a machine tool (see photo at right) or a surface plate on a close-by inspection bench. The measuring arm offers 0.0002-inch accuracy, which reflects the increasing need of shops to hold "tenths" tolerances.

Part measurements are recorded on a laptop computer equipped with the company's Cam2 Measure software developed for feature measurement/inspection and CAD-to-part comparisons where every measured part can be compared to engineering design files. The software is user friendly enough that it can be used by machine operators with no computer skills as a step-by-step guide through an inspection routine. It not only tells the user what area of the part (top, bottom, left side, and so forth) to measure next, but it also tells him or her where and how to position the probe for the reading. The software can also be used for advanced measurement and statistical analysis such as SPC and geometric dimensioning and tolerancing (GD&T). The system records all of the user's measurements automatically and creates comprehensive reports The gage allows the part to be inspected right on the machine, which not only saves time but also avoids the problems that come with removing the part from the machine, inspecting a critical feature and trying to put the part back in the fixture exactly the way it was before. It can be used for a variety of measurements that might otherwise require several conventional hand tools, eliminating their costs and maintenance. It also eliminates the variation in measuring results from hand tool to hand tool and from operator to operator. The gage's articulated arm enables it to measure features and relationships between features that would be impossible to measure with conventional hand tools. Plus, automatic recording of the inspection data eliminates "pencil and paper" errors by operators responsible for maintaining SPC charts.

Right-Now Results

Perhaps best of all, the machinist can check the part immediately after it is machined--or pause to check a feature while the part is still in the chuck or fixture--right at the machine and replace a worn insert, change a tool offset or in some other way make an immediate correction to avoid making bad parts. The operator is also spared having to leave the machine, carry the part to the quality department, and wait in line for time on the CMM.

According to the company, in shops where a machine tool stands idle for 1 hour per shift (at $75 per shift, 3 shifts per day) because it must wait on an operator who is busy inspecting the previous part, the FARO Gage will pay for itself in 4 months. It takes up no extra floor space, an important consideration for crowded shops, and it easily can be moved from one machine to another