Re: [CAD_CAM_EDM_DRO] Aluminium as Electrode

Roland,

The biggest problem that I see is that aluminum is a difficult material
to work, with electrically speaking. An insulating aluminum oxide layer
forms instantaneously upon exposure of the bare metal surface. This
self-protecting oxide is why aluminum doesn't seem to rust. It actually
does oxidize, but the oxide layer is very thin, tough and adherent, and
protects from further damage. It is also electrically insulating.

Al is used in electrical wiring, but you have to use antioxidant
compound on the terminals to assure good contact.

Don't know how it would work for EDM. I suppose you could try a test
piece and see if you get anywhere.

Dave

Roland Jollivet wrote:

> Hi All
>
> Just joined and first post;
>
> I'd like to know if anyone has had any experience with using Aluminium as an
> electrode?
>
> The scenario is that I want to build an EDM circular saw to cut tool steel.
> Now normally, a copper or brass disc is used. However, finding suitable
> material, shim like, but FLAT, is a bit difficult. However, Aluminium sheet,
> 0.15mm, is available by the truckload, flat, neatly packed, and cheap.
>
> I understand the virtues of copper, brass, graphite as electrodes, and how
> easily aluminium is eroded as a target, but I'm really battling to find any
> info on Aluminium specifically used as the electrode.
>
> So, the question is, will it work, or will the Aluminium get chewed up so
> fast so as to be not worthwhile?
> (PS, cut feed/speed is not an issue, it can run all day)
>
> Regards
> Roland Jollivet