Question for users of milling machines

snipped-for-privacy@aolbin.com wrote in news: snipped-for-privacy@mid.individual.net:

As an ex-Jig Borer I would use a Mercer dial indicator in a jointed arm in the spindle and rotate it to touch each side of a slip gauge - adjusting until I got equal readings and then pitch over by hald the slip gauge size. Alternatively I had a block with a should that I could hold onto the edge that had a slot centred over the shoulder. Rotate the dial indicator to get equal readings.

JohnP snipped-for-privacy@nowhere.com wrote in news:XnsAC6D89F91798EJohPnowherecom@81.171.92.222:

I recall a wiggler being put through a test on a neigbouring SIP No7 Hydroptic. It was very good - but they never caught on. .

I'm probably about to expose my lack of knowledge, but how does that help find the edge of an object that you want to machine?

snipped-for-privacy@aolbin.com wrote in news: snipped-for-privacy@mid.individual.net:

Imagine using a dial indicator (finger type) in the spindle to fins the centre of a slot. This is the same principle - but finding the centre of a block or a slip gauge.

Aha! Thanks for the link; light has dawned. Is there any advantage compared to a capacitive edge finder, for example?

Such things were not around when I was a Jig Borer. Renishaw probes were just being seen.

I have always used a Wobbler, but you have to take into account the backlash of your lead screws when further advancing from the now-found edge to your centre of the workpiece.