QuestionQUESTION: I would like to make a ring for my wife. The stone to be used has a complex symbolic history that is not all pleasant. As a symbol of the stone's history, I would like to cast a gold ring over an iron mandrel -- leaving the iron showing only through selected windows.
The plan -- dip the mandrel in wax. Scrape away the places that iron should show, then replace the wax with gold via casting.
The thermal coefficients of expansion seem close enough -- can you suggest a flux that might insure that the gold and iron bond?
ANSWER: I am out of town and wanted to reply quickly to your question. I usually use my computer to verify all my info, but only have my phone with me tonight. Off the top of my antique head I don't remember it but I do remember where I learned it. Oppi Untrecht I believe is the author of the book "metal techniques for craftsmen" is a plethora of usefull information, if I am not mistaken the information you seek is in this book....also a good addition to your reference library. Please let me know if this doesn't answer your question when I return home I will try to find the correct flux. I believe boric acid & alcohol may be an appropriate choice. Please let me recommend you look it up in the chapter on mixed metals.
Thanks for your question,
Chris
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QUESTION: Chris,
Thank you for the reference. Since I do not have quick access to the book, please do verify your memory when you return home.
The book is available though our library network, but not immediately. Sadly, it is not available as an e-book.
AnswerWoodie, I have asked around and done extensive research. It probably isn't the best way to try to cast directly onto Ferrous metal. the heat process of removing the wax is one thing that will tend to destroy your finish and the final fit together is also usually very unsatisfactory since gold is so much softer than Steel. I recommend you make them to fit together and then rivet them in place by drilling the steel and riveting the gold in place through the steel with an like karat rivet of gold. this will insure they remain in place securely and do not move also you can finish the pieces separately and they will maintain their finish without heat distortion of casting or soldering. Perhaps a machine shop could use a lathe to insure an accurate fit witch should be much more aesthetically pleasing.
Let me know what you think.
C
