Re: [Harp-L] What is Wire EDM?

[Rick Dempster <rickdempster33@xxxxxxxxx>]

Whew! Thanks Robert.
RD

On 2 April 2016 at 06:07, Robert Coble <robertpcoble@xxxxxxxxxxx> wrote:

> Rick asks:
>
> "EDM? Whats' EDM? Electronic Dance Music....google google....ah!
> Electronic Discharge Material......? Yes? But what is that anyhow?"
>
> Answer:
>
> Electrical discharge machining (EDM), sometimes colloquially also referred
> to as spark machining, spark eroding, burning,
> die sinking, wire burning or wire erosion, is a manufacturing process
> whereby a desired shape is obtained using electrical
> discharges (sparks).[1] Material is removed from the workpiece by a series
> of rapidly recurring current discharges between
> two electrodes, separated by a dielectric liquid and subject to an
> electric voltage. One of the electrodes is called the
> tool-electrode, or simply the "tool" or "electrode", while the other is
> called the workpiece-electrode, or "workpiece".
> The process depends upon the tool and workpiece not making actual contact.
>
> When the voltage between the two electrodes is increased, the intensity of
> the electric field in the volume between the
> electrodes becomes greater than the strength of the dielectric (at least
> in some point(s)), which breaks, allowing current to
> flow between the two electrodes. This phenomenon is the same as the
> breakdown of a capacitor (condenser) (see also
> breakdown voltage). As a result, material is removed from both electrodes.
> Once the current stops (or is stopped, depending
> on the type of generator), new liquid dielectric is usually conveyed into
> the inter-electrode volume, enabling the solid particles
> (debris) to be carried away and the insulating properties of the
> dielectric to be restored. Adding new liquid dielectric in the
> inter-electrode volume is commonly referred to as "flushing". Also, after
> a current flow, the difference of potential between
> the electrodes is restored to what it was before the breakdown, so that a
> new liquid dielectric breakdown can occur.
>
> Crazy Bob
>
>
>