I found a film added in May 2021 by the National Film and Sound Archive about a small foundry located in Sydney, 1984. I wonder how much longer it operated for after this was filmed, it shows some good shots of maintaining a cupola furnace lining and making green sand moulds of iron work for building railings etc.. This sort of local manufacturing is now long gone and I suppose the demand for architectural ironwork to restore older buildings has waned.
Thanks for the link Mark. 1984 was when I built my first furnace. There were still small foundries in Perth; the last one I smelt from the petrobond as I walked past, would have been in about '95, Cheers Charlie
There was a guy on Gumtree at Perth a couple of years ago selling Morgan branded silica fibre blocks of furnace insulation, they were 30cm cubes and would peel off in sheets. I bought a couple of boxes and he seemed to have a lot stashed in a shed.
Here is a foundry in country Victoria with a cupola and is still operating. They did get induction furnaces and use self setting sand and maybe that is why they are still operating today.
That was a good video to watch, got some interesting ideas from what they were doing. You can see how easy resin sand is to use: fill the pattern, give it a light tamping and screed off the excess and few minutes later it's ready to extract from the pattern.
Did you watch this video by that foundry, goes in detail about making the molds for camp ovens using self setting resin. The most interesting part is where he just slops on the mold paint and then spreads is with compressed air.
I had a look at all their videos, it's a pity they don't do more of them. I was wondering what the coating actually is, the compressed air forces it into the sand pores. It looks carbon based at a guess, like bitumen thinned out which would supply carbon once the volatiles are burnt off. It might be a good use for old copier toner (carbon black and styrene binder) if you burnt it off first and stayed upwind.
