L.E.D. Touch probes (touch point sensors) & manual edge finders are used primary on milling machines & CNC machine centres to locate work piece’s edges or bores, thus enabling to a datum point or centre. Similarly to locate vices, fixtures etc on a machines table as a reference point. Other common names are touching point sensors, wigglers, wrigglers, centre finders, electronic edge finder, digital edge finder.

 Touch probes & edge finders can eliminate set up using a dial test indicator in most cases.

 The L.E.D. touch probe can be battery operated, mostly have inbuilt “beeper” as well as a red L.E.D. lighting up on contact, this contact can be then zeroed on the machine, also confirmed on exiting the job. The touch probe has a run out spring fixed to the contact ball to prevent breakage. Accuracy within 0.005mm. Winding in manually on a CNC milling machine is essential.

The contact ball or point of the touch probe is 10mm, so easily halved (+ or - 5mm) to find the true spindle centreline of the edge. The L.E.D. touch probe is used with the spindle stationary; unlike the edge finders have the spindle rotating aprox. 500 RPM.

The edge finders & wrigglers require the spindle to be rotating so as the edge finder passes it concentric centreline it “jumps”, so this sudden movement of the edge finder or wriggler can be seen visibly & clearly. It is common to also have a centre finder point on the opposite end of the edge finder tool or a centre finder point in a wriggler set. The centre finder is great to locate and pick up centre pop marks or scribed lines.

Renishaw probe systems provide an innovative solution to improve the efficiency of your machine tools.   Touch probes on CNC machining centres and lathes can be used to identify and set-up parts, measure features in-cycle for adaptive machining, and verify finished component dimensions. Save time. Reduce scrap. Stay competitive.

“3D Tasters” are a great edge finder, which allow Z axis travel as well. 3D Tasters offer a huge advantage of the stylus point diameter is already compensated for by advancing to zero out the dial – eliminating potential mistakes on the datum line & - or + stylus diameter.