[TheForge] reclaiming copper

[James Binnion]

Bill Amen taught me how to sand cast many years ago in Manitou  
Springs Colorado, he was an amazing character. His books are full of  
good information but very dated.

re humidity copper will absorb both oxygen and hydrogen causing gas  
porosity problems but humidity is not a first order problem.

The problem with wire as you say is that it  has a large surface area  
to volume ratio and will heavily oxidize. Flux alone will not take  
care of this. You need an active degassing procedure , one method is  
the addtion of phosphorous, lithium or other material to remove the  
oxygen from the melt. The degassing is done right before pouring.  
Pure copper is one of the most difficult metals to cast due to its  
afinity for oxygen and hydrogen and its high viscosity.


Jim

On Jun 30, 2006, at 6:27 AM, Grover Richardson wrote:

> 	Get the book by Amen on non-ferrous casting.  He talks a lot about
> copper and melting.
>
>
> Things that I remember:
>
> 1.	Don't melt copper in a high humidity atmosphere if you expect to  
> get
> the best quality.
> 2.	Wire has a large surface area to mass ratio and therefore usually
> oxidizes heavily.  The resulting copper oxide is not desirable and  
> harder to
> deal with (for some reason that I don't remember).
>
> If you wish, I can look for my copy at home and get the isbn.  I  
> think I
> purchased it from Centaur Forge.
>


James Binnion
jbin at well.com