Saturday, August 4, 2012

Melting metal at Chalupy

First of all, this is not my project. It is all John's doing. Second of all, what you will see is not entirely as safe as turning on your kitchen stove. It can be dangerous. In these litigious days be very careful and wear proper safety gear, blah blah. Consider yourself warned. Chalupy Acres disclaims all resposibility, blah blah.

What we are doing is melting Aluminum to (eventually) make castings. Before you do this for yourself, you must read the sources. We acknowledge hereby these sources. The first and most inspirational is the late lamented Dave Gingery's "Build your own Metal Working Shop from Scratch" series, 6 volumes. The first is The Charcoal Foundry, all available from Lindsay Publications. From the same source get Lionel Oliver II's The Flowerpot Crucible Furnace. Very cheap stuff, I may add.

Finally get on the net. Go to Myfordboy's blog; it should appear on the sidebar on this blog. Select his channel on YouTube. There are 30 videos (as of today) on casting; you should watch them all.

OK, on to melting metal. John built the forge. We started out with the idea of a Gingery/Oliver smelter. This runs off grocery store charcoal, the kind you use to barbecue steaks.
The basic forge involves (1) a 5 gallon Kerosene drum, main part of the thing (2) a clay flowerpot. This is imbedded in a concrete lining. The concrete is just Home Depot (or was it Lowe's?) standard stuff. There is a hole cut through all this. A piece of galvanized pipe goes through it all. In forge-speak, this is called a tuyere, the french word for "piping". A hair dryer, long defunct, provides air. With this setup you can melt Aluminum. John soon found that the Dragon Lady is a far preferable substitute. The Dragon Lady has appeared on these pages before. She is a heavy-duty propane torch bought from Harbor Freight for $13 back when. She melts snow, clears out weeds, starts charcoal fires. As it turned out we could have dispensed with the charcoal.
John is very happy. Aided by the Dragon Lady he has melted Aluminum. Lovely stuff, melted Ally. Looks like silver or perhaps like Mercury. The big pipe holds a stainless steel spoon, used to skim off the dross. This is junk, impurities you do not want. Today John will pour Aluminum cupcakes; we are not yet into making real molds.
John added common salt as a flux (makes things flow) and baking soda as a degasser. About a teaspoon each. Very effective and thank you Myfordboy. We are using fireplace tongs to hold the crucible, the container in which you put the metal. This I found long ago at a thrift store for two bucks. It is a plumber's pot originally meant for melting lead. A bit more close to the pouring process we have

At the end of the road we have taken some literally castoff Aluminum-- it was stuff I found by the roadside on a bike ride and went back and salvaged. We produced two cupcakes -- as I have said we are not yet up to casting into molds -- each weighing about 100 grams. Ten cupcakes to a Kilo. The potential is endless. John wants to make the Gingery Lathe. Refer to the sources.

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