With help from Ben, I've fired up my forge again and smelted some bronze. The Winter is coming in these parts, and the surrounding bush is now sufficiently damp for me to not worry about setting it all on fire. Just to make sure we're now sporting a spark arrestor. This year the forge has a 110mm centrifugal 12V blower that I printed myself on the RepRap:
The blower is in turn powered by a car battery with a dead cell, charged from a 5W solar panel strapped to the awning. I just drilled 4mm holes into the battery terminals and use 4mm banana plugs for everything. As a bonus, I can plug in a LED spotlight which lights up my nocturnal smithing activities.
The flowerpot used as the forge's firebowl has fragmented, but it was far too deep anyway. Time to spend another few bucks at the garden centre and get a more bowl-like flowerpot. But we're back working metal again, and this makes Winters bearable for me!
I hope to cast bronze in plaster moulds made from RepRap'd cores, but for this test we just cast it into a crude charcoal mould.