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Just saw this listed on Ebay. http://www.ebay.com/itm/Victor-Phonogra ... SwKtVWwO4b How would that work?
I don't know why my text is so spaced out. Tried to edit it but can't fix it.

I think this was used to make reproduction back brackets.
Harvey Kravitz

Phonofreak wrote:I think this was used to make reproduction back brackets.
Harvey Kravitz

Wouldn't it have to be a metal mold? I don't see how you could pour a metal back bracket in a wooden mold.

phonogal wrote:

Phonofreak wrote:I think this was used to make reproduction back brackets.
Harvey Kravitz

Wouldn't it have to be a metal mold? I don't see how you could pour a metal back bracket in a wooden mold.

They are patterns which are always made of wood. One uses them to make a mould out of casting sand, then pours in the molten metal. Cast iron for a Victor bracket one would assume.

https://en.m.wikipedia.org/wiki/Pattern_(casting)

Panatropia wrote: They are patterns which are always made of wood. One uses them to make a mould out of casting sand, then pours in the molten metal. Cast iron for a Victor bracket one would assume.

https://en.m.wikipedia.org/wiki/Pattern_(casting)

Interesting. Thanks for the link.

I saw this process done at Bethlehem Steel. They had a brass foundry, an iron foundry, and a steel foundry. They made many of their own parts for plant machinery. In conjunction with this, they had a pattern shop. Interesting to me was the fact that, because metal typically shrinks as it cools, the pattern has to be slightly larger than the finished item (just how much larger depends on the particular metal being cast), and to allow for this shrinkage the patterns were made with special rulers that were graduated into slightly larger units. IOW, an inch on the ruler was longer than a standard inch, and so on. And there were many rulers with different sizes of inch, depending on which metal was being cast. Fascinating! And now totally gone. I hope some of these skilled professional pattern makers, who are really highly specialized woodworkers, have been able to practice their art elsewhere since the plant closed. Also, today the craft has been supplanted by CAD and automated (i.e., computerized) processes, remarkable in themselves.