Hello david, If purchasing these melting casting compounds I can help
given you an address: Due to your rather high pond prices towards the
Euro it would be not expensive for you.
In the Netherlands it is available at “Bijou Moderne” in Bleiswijk tel
+31 10 5296600 Fax +31 10 5290088 Mail email@example.com The Dutch
price for Auro purifax is Fl 19.20 incl tax. for 45 gram Normal
melting compound Fl 20,- for 500 gram.
It is also available in Germany at Karl Fischer GmbH Pforzheim tel:
+46 7231 31 0 31 Fax: +46 7231 31 0 300 Mail firstname.lastname@example.org
And : www.fischer-phorzheim.de German price is DM 12.00 excluding tax
(I think 19%) for 40 gram and DM 219 for 1 Kg.
What do you mean, what does Sodium carbonate (Na2CO3) do? If you mean
in melting, I do not now I think it will only burn away, I know it is
sometime used as a soot solver in heat exchangers. This would mean it
will react with carbons and will work as a very light oxidiser. The use
I have for Sodium carbonate is, neutralising the jewellery after
Ammonium Chloride is a I know NH4CL, This does need a lot of oxygen
for burning. The heat will break it up in I think NH3 and HCL again.
This means it will react with copper oxides and will build chlorides.
It should work than as a deoxidiser of the copper in the melt. But may
be this salt it will melt to fast I think I will try it for some
experiments. I know that we can buy this stuff as salmiac stones for
cleaning soft soldering irons tips.