|
Post by piousheretic on May 21, 2011 22:37:06 GMT
I recently learned some very interesting information regarding what might be called "quality control" in casting. I've added an attachment below with a wealth of information, but as a general overview: Apparently different metals oxidize at different temps and only a very small percentage of the dross that forms on the top of your pot or ladle is from the lead. It is, rather, the other metals in the alloy such as the tin, bismuth, antimony, etc. What this means is that when you skim the dross off of the top of the pot you are actually changing the alloy mix, generally taking out the metals that make the alloy pour easier, contract less in the mold, and fill in the details – all of the good stuff in other words. I would guess that this is, at least in part, what is responsible for the alloy getting “crumbly” the more you re-melt it. The majority of this dross can be fluxed back into the mix. The article in the link suggests various fluxes, including paraffin wax or sawdust. I tried using sawdust flux today and it seemed to work like magic. Here is the article: www.lasc.us/FryxellFluxing.htm
|
|