Casting and Working Pewter
Since nearly all metals excepting tin and lead have high melting points, it is hard to melt them unless you have a regular furnace.
Something About Pewter.
—But casting metals is a fascinating process and you can do it by melting 25 parts of lead and 75 parts of tin together which forms an alloy called pewter.
This alloy is as old as the hills and for ten or eleven centuries before the golden age of invention—that is to say the beginning of the 19th century—pewter utensils were used in nearly every home in every civilized country.
Then came the invention of cheap processes for making pottery and glass and those good old hard alloys known as britannia metal, which is formed of tin, copper and antimony, and German silver, which is German all right, for it was first made at Hildburghausen, Germany, but it is not silver at all for it is formed of nickel, zinc and copper, went entirely out of use.
But there is a dignity and a beauty about pewter that none of the other common metals have and it may be revived one of these days for efforts are now being made to produce it again in all its former glory.
How to Make Pewter.
—I do not know of any place where you can buy pewter but you can easily make the alloy yourself.
You can get the lead in your home town wherever you live at any plumbing shop but you may not be able to get the tin so easily. You can, however, get it by sending to the Conley Tin Foil Company, 521 West 25th Street, New York, and at the present time they are quoting pig tin in blocks at 75 cents a pound.
When you have the lead and the tin melt the lead in an iron ladle, see [Fig. 39], over the kitchen fire and skim off the dross, that is, the impurities in it that come to the surface, and then put in the tin. After both are melted stir them well and then pour the alloy thus formed, which is pewter, in a pan that is oiled with sweet oil, to keep it from sticking and so make sheets of it of whatever thickness you want.
Fig. 39. iron ladle for melting pewter
About Working Pewter.
—Pewter can be worked like any other malleable metal, only easier because it is softer and more ductile, hence it can be hammered into any shape.
It can be cast as you will presently see and it can be soldered by using a flux of tallow, Gallipoli oil or Venice turpentine and pewterer’s solder, which is made of 1 part of lead, 1 part of tin and 2 parts of bismuth.[32] This solder melts at 203 degrees Fahrenheit, that is at a temperature of 9 degrees less than that at which water boils.
[32] Bismuth is a reddish white metal.
How to Cast Pewter.
—The way in which pewter is usually cast is by making molds of iron and brass and pouring the metal into them. But you can do a very good job of casting pewter by making and using plaster of Paris molds.
In making any kind of castings you need a flask, that is a wooden frame made in halves, as shown in [Fig. 40]; the top half of the flask is called the cope and this must be fitted with pins that set in holes in the bottom of the frame or drag, as it is called.
Fig. 40. how a pewter casting is made
When these pins set in the holes they keep the top and bottom parts of the flask together so that after the mold is made they can be taken apart and the pattern removed and then when they are put together again ready for the metal to be poured they will be exactly even. Make the top and bottom halves of the flask a couple of inches larger all round and a couple of inches deeper than the size of the pattern you are going to cast.
The Patterns Necessary.
—You can saw or turn or carve out of wood anything you want to cast in pewter, provided it is not too intricate, and after sandpapering it nice and smooth all over give it a couple of coats of shellac varnish.[33]
[33] This can be bought already made at paint stores or you can make it by dissolving some yellow shellac in alcohol.
If it is your idea to make table-ware of pewter you can use ordinary china dishes for your patterns, provided they are without handles, but before making a mold with any kind of a pattern in plaster oil it well all over with sweet oil, using a brush for the purpose, so that it will not stick and then you can draw it easily.
Making the Mold.
—Lay the drag, that is the lower half of the flask, on a board or a table; mix dental plaster of Paris with water until it is about as thick as batter and fill the drag with it.
Just before the plaster begins to set, that is, harden, take your pattern, whether it is one you have made or a china dish, oil it and press it down into the plaster until it is nearly even with the top edge of the pattern and let it stay there until the plaster is hard, that is, over night.
Then brush sweet oil over the top of both the pattern and the hard plaster which must come about flush, that is even, with the top of the drag. Now put on the cope and fill it with plaster, smooth it off even with the top edge and let the plaster get hard.
Your next move is to lift the cope from the drag which you can do without trouble and then lift the pattern from the drag, using the point of a knife if it seems inclined to stick.
Drill a ¹⁄₄ inch hole through the plaster in the cope, fit the cope to the drag again and then pour in the pewter. When it is cold take the flask apart, take the casting out gently and don’t spoil it even if you have to break the mold.
Where cups, tankards or other hollow vessels are to be cast make a mold for it just as though it was a solid piece; now pour in the melted pewter and when it has cooled enough to form a solid layer turn the mold upside down and let the melted metal run out which will leave it hollow. If handles are needed cast them separately and solder them on to the body of the vessel. Some finished pewter ware is shown at [C].
Fig. 40c. home made pewter ware
Finishing the Ware.
—Plates and the like can be scraped with a steel scraper and when they are nice and smooth rub them with a rag dipped in oil and whiting, but do not polish them.
If you have a turning lathe of any kind you can put your cups and other round objects in it and turn it up with a bent inside turning tool, a flat tool and a round point tool such as is used for turning brass, ivory, etc., and which you can buy for a quarter apiece,[34] and this will leave the pewter bright and beautiful.
[34] These tools can be bought of Luther M. Wightman, Milk Street, Boston, Mass.