Shop rolls video for tool measuring

Jan. 27, 2006
Denny's Tool Mfg. Inc., produces and regrinds cutting tools, and meeting tolerances

Denny's Tool Mfg.'s Anca RGX CNC tool and cutter grinder incorporates an iView video tool-measurement system.

For Denny's Tool Mfg.'s complex tool forms, the iView speeds production and improves grinding accuracy.

Denny's Tool Mfg. Inc. ( produces and regrinds cutting tools. Meeting tolerances of ±0.0001 in. on diameters in carbide and HSS when grinding inside/outside forming tools, step tools, counterbores and more is standard operating procedure. To quickly and accurately grind such complex tools, the shop uses an Anca ( RGX CNC tool and cutter grinder equipped with an iView video tool-measurement system.

The system includes software that works seamlessly with the grinder's machine-operating software and a camera that mounts inside the work envelope for measuring. iView delivers a magnification of 300:1 and accuracies as close as 2 microns.

According to Dennis Wilfong, president of Denny's Tool, iView saves a lot of time and contributes significantly to accurately grinding even the most complex forms. The shop quickly measures shapes, profiles and outer diameters of cutting tools that remain clamped in the grinder, then compares those measurements to ideal tool geometries with the system.

Prior to using iView, the shop removed tools from the machine, checked them on a comparator, made necessary machine corrections, re-chucked the tools, touched off for location, and re-ran the programs.

"Keeping tools in the machine saves time and increases accuracy, letting us turn more jobs around in short time periods," says Wilfong. "And the RGX repeats so well that we only have to check a few tools during a run."

In operation at Denny's Tool, iView software generates ideal shapes for standard tool geometries and protracts them over actual tool images. For complex tool profiles, it imports DXF overlay files. The camera captures high-visibility images of the ground tools, then compares them to the as-designed overlay shapes.

"iView makes it extremely easy to see where the form is right and where it is off before the tool is completed, and in time to make adjustments to the machine program," says Wilfong. The grinder automatically makes corrections, or the shop does them manually. Denny's Tool also can superimpose a 0.0002 in. grid or auto shadow graph over the tool for instant measurements.

Images are stored in graphic file formats. In manual mode, operators are able to click on the necessary program line, indicate how far off a tool shape is and re-run the tool without removing it from the machine. For automatic measuring, the system positions the tool overlay over the corresponding point on the ground tool. Operators acknowledge the measured point, and the machine advances to the next predetermined point.

Wilfong says one tool comes to mind when he considers the benefits of the iView system, an inside rotary-recess tool that had several different angles along its length. Inspection with conventional methods would have taken a long time and would not have revealed all of the tool's features.

The iView overlay technique let the shop easily see whether the proper clearances on flutes and edges were present through the system's ability to measure 3-point angles, 3-point radii and 2-point distances as well as the DXF imported overlays.