Northfield Precision Instrument Corp. reported that when a customer requiring a highly specialized diaphragm chuck was not finding success with other chuck manufacturers, they turned to Northfield Precision Instrument. The chuck needed to be submersible for use in a wire EDM. To achieve this, the engineers at Northfield designed a specialized chuck with all non-stainless steel wetted parts.
For ultimate protection in a corrosive environment the chuck was fully coated with a thin, dense layer of hard chrome. In addition, the top tooling had to be custom designed to hold the customer’s specialized part (not shown) to within 0.0002” TIR accuracy and repeatability.
Related Glossary Terms
Workholding device that affixes to a mill, lathe or drill-press spindle. It holds a tool or workpiece by one end, allowing it to be rotated. May also be fitted to the machine table to hold a workpiece. Two or more adjustable jaws actually hold the tool or part. May be actuated manually, pneumatically, hydraulically or electrically. See collet.
- electrical-discharge machining ( EDM)
electrical-discharge machining ( EDM)
Process that vaporizes conductive materials by controlled application of pulsed electrical current that flows between a workpiece and electrode (tool) in a dielectric fluid. Permits machining shapes to tight accuracies without the internal stresses conventional machining often generates. Useful in diemaking.
- total indicator runout ( TIR)
total indicator runout ( TIR)
Combined variations of all dimensions of a workpiece, measured with an indicator, determined by rotating the part 360°.
- wire EDM
Process similar to ram electrical-discharge machining except a small-diameter copper or brass wire is used as a traveling electrode. Usually used in conjunction with a CNC and only works when a part is to be cut completely through. A common analogy is wire electrical-discharge machining is like an ultraprecise, electrical, contour-sawing operation.