Originally Posted by mantrid
I frequent a metal casting forum
Its US based and there are some guys there that Im sure would be near where you live and could do this for less than your foundry quote.
They are a friendly bunch and would probably be willing for you to go around and watch or even take part in the process if you wanted.
It is a slow process to register for this forum so if you dont want to be bothered with it I would be happy to post a request there for you.
Thanks Mantrid, I already joined, I think I've read that site or it's sister, no doubt have it bookmarked long ago.
Thing is, my waxes for these were all made in complex plaster/sand piece waste molds because at the time (pre internet) there were no mold rubbers I felt comfortable using for so fragile and complex a wax with all the undercuts and my resources of finding something back then was limited. Since I never had a hard master model (all were plasticene) I only have the master rubber block molds (made of Polytek 74-40) with their plaster mother shells to use.
The rubber is still in excellent condition even after 22 years, the thing is to cast the waxes today I have to use those to cast all the pieces of each mold in the 50/50 plaster/sand mix I used (breaks apart and disolves in water very easy with the sand added) and then I soaped the plaster/sand pieces when dry and cast the wax when dry.
The thing is, that took so much time and work just to get a wax that I don't want to take a chance having it cast by anyone other than a regular foundry, both Parks and Weston cast the bronzes for me and never had one problem, I suspect some hobbiest with a "backyard" setup would have amuch higher rate or risk of failure, and then I'd have to spend another half a day casting a new wax and chasing it.
I am interested in looking at the site for ideas since casting aluminum and bronze, as well as pewter have always been an interest and I want to do something again.
I cast two of these dog models myself in Brittania metal back around 1992, I used a plaster/sand mold the same as though I was going to cast wax in it, I made a plaster/sand core (though I don't remember how I got the shape, maybe used a wax cast as a sacrifice to do it and poured it full of plaster/sand)
Then I held the core in place with some small brass pins, heated it up in my kitchen oven for most of the day to get it good and dry, set it in a container full of sand and poured the Brittania metal in, as I remember it took about 12# of metal to cast each.
Both came out reasonably well, needing only some minor chasing.