It is great to see someone making their own castings.
Its a bit tricky to get the method(s) down, but once you do, you can make some great castings.
Those are respectable casting you have made.
I learn a bit more about foundry work with every video I watch.
Brass has always been a nightmare for me to try and cast, with the zinc boiling off, and trying to get to a decent pour temperature before all the zinc burns off.
Someone said try a glass cover with brass.
I hope to make a bronze alloy, and avoid brass altogether.
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Making your own brass may be best way. Charts of mixes may be found online. I buy scrap copper or brass from junkers.
But certainly, put broken clear glass on top of the brass, but before you worry about that, forget yellow brass zinc brass (which causes zinc chills, always drink tomato juice during and after pouring, and never soda pop), I seldom cast yellow brass, do not use that material. That is cheap junk for nic-knacks and plated water outlets.
I use old water valves or machinery brass-bronze, 85% copper, 15% tin for machinery or lead for a red brass.
Best to do your own research for contents. Any more, I just melt red brass scrap from the scrapyard. It has been some time since I worried about numbers. When buying brass from scrappers, I sell the yellow for scrap and melt the red.
I do not mix the bearing or valve brasses, and never mix yellow, it floats on red brass and makes ugly blotches.
When melting red brass, for time sake I cut the pipes and leave the steel in them as it floats like wood when molten. But one must always remove aluminum, it makes glass hard castings, although there is an aluminum bronze.
If your having trouble pouring yellow brass for cold shuts, it is not hot enough, note if you can see the brass in the pot when molten, it is not hot enough. It should be blinding to the naked eye. Like cast iron. I flux yellow brass by dunking potmetal carburetors in the molten brass.
I use welding flux or phosphorus in red brass. It makes it flow. I always keep brasses covered with flux or a lid.
I also use bottom pour crucibles.
I trickle nitrogen through yellow brass too.
Or sometimes I use a bronze that flows like water, just as easy as cast iron. Very liquid, I buy this from Lancaster Supply at Lancaster Pa. I think they sell it to statue makers and call it silicon bronze.
My custombers hate machining it.
Hope this info helps some one.
Also always pour brass like a bell, upside down like. Ledges go up, with no vents on tops or tips. Crap floats up. Vents go out along bottom or centers of part.
I do not know what others do, this just works for me. Of course use lost wax in spinning molds if you can, for intricate parts.
I cast model bits and tags in expensive jewelers sand. Costs about a hundred dollars for a good sized molds worth.
but I would say encouraging
