Re: Digitizer probe progress

I realise my example digitize wasn't a good one as it was a metalic
object and could have been digitized in just the same way as you
describe. I should have gone for a plastic object really.

Cheers,

Graham

p.s. Next one is going to have to be ultrasonic.




--- In CAD_CAM_EDM_DRO@yahoogroups.com, "tomp_tag" <tomp_tag@i...>
wrote:

> Yes, it detects where the tool is. it (should) slowly crash into

the work.

> so slowly and so carefully that it doesnt hurt anything or move

anything.

> In CNC EDM, we use detect voltage drop to determine when the tool
> (plus) touches the work (-). When the voltage difference dissapears,
> we know we 'touched, and record this data.
> For what? well we can touch the top to determine the surface

height.

> We can touch a bunch of tool to some surface to find tool length
> differences. We can touch two sides to find a middle, or 4 to find
> a center.
> Some mills do this with a 'skip cycle'. So if you can insulate the

work

> or the tool ( either one ) a 12 volt dc source at maybe 50 to 100

mA

> can be used as the sense voltage, and it's absense can be detected

to

> trigger a position capture in the CNC.
> tomp