Some questions about making wire

Jewelry Discussion
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I have been following (and a member) of this community since I began taking jewellery and goldsmithing classes in 2019. I was looking for information about the following but couldn’t find it, though I’m sure it must be here.

  1. The first is about calculating the ratio of grams between fine gold and silver. I have a Hans Meevis ingot mould which I used the other day for the first time and it was wonderful. I had watched Andrew Berry’s video. He said the measures on the mould are for increments of grams in silver and that to cast a gold ingot would require calculating the difference? How would I do that and is it necessary?

  2. My next question was about drawing down wire. I have drawn down a fine silver ingot to 20ga in my Durston mill. I need 22ga and could get it to that in the mill but I want round wire and much longer. Should I stop now and use a draw plate; or if I continue with the mill to 22ga will a draw plate stretch and round without thinning? (I think the answer is “no, it will also thin,” but want to check).

  3. My last question is about a term used in posts I read–“flashing” when drawing down wire. I tried looking it up but without success. What does this mean.

Thank you for all the wonderful posts. I learn so much here.

Shelley

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Go to the url below to find a weight comparison chart of different metals. Roll to maybe 18 gauge and then draw to 22. Flashing happens when you close the rollers too much and take too big a bite with the V grooves. Metal squeezes out into the open space between the rolls forming a thin irregular line of metal. You either start over or grind/sand it off. This is why you take little bites and anneal often. Good luck…Rob

https://www.kitco.com/jewelry/weightcomparison.html

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hi Shelly,
regarding your question #1, have a look at the below link discussing Specific Gravity.

https://www.gemologyproject.com/wiki/index.php?title=Specific_Gravity

and this specifc gravity by metal type link

http://www.hauserandmiller.com/reference/melting.html

and perhaps search this forum for Specific Gravity

Julie

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hi, I just thought this was a good example to illustrate the concept…

https://www.gemologyproject.com/wiki/index.php?title=Specific_Gravity

"Consider two balls of equal weight but of different specific gravity, for instance a 10 gram gold ball and a 10 gram silver ball. The gold ball has a sg of 19.3, while silver has a sg of 10.5.
Because gold has a sg that is almost twice as much as silver, you can imagine that the 10 gram gold ball will be smaller than the 10 gram silver ball. In other words, the gold ball will have a smaller volume than the silver ball.

When you hang both balls in water (immersed), then the silver ball will displace much more water than the golden ball due to its higher volume."

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Thank you, Julie. I’m not sure what I’m supposed to be looking at in the links you provided. They seem complicated to what I wanted to know–which means I didn’t ask the question properly. What I understood from how to use the mould, which allows one to measure out the size of ingot one wants in length and width, was that the measure marks are for fine silver ingots. I should probably just ask Hans Meevis who designed the mould. I appreciate your help.

Shelley

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Thank you, Rob, that’s what I thought flashing meant. Thank you also for gauge to roll to before using draw plate.

Shelley

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This is such a clear answer to my question. Thank you so much. I understand now. Appreciate it.

Shelley