For mixing and preparing the sand a small shovel, D, and a sieve, E, will be required.  If desired the sieve may be homemade.  Ordinary wire netting such as is used in screen doors, is about the right mesh, and this, nailed to replace the bottom of a box, makes a very good sieve.

The rammer, F, is made of wood, and is wedge-shaped at one end and flat at the other, as shown.  In foundries each molder generally uses two rammers, but for the small work which will be described one will be sufficient.  An old teaspoon, G, will be found useful in the molding operations and may be hung on the wall or other convenient place when not in use.

The cloth bag, H, which can be made of a knitted stocking, is filled with coal dust; which is used for a parting medium in making the molds.  Take a small lump of soft coal and reduce to powder by pounding.  Screen out all the coarse pieces and put the remainder in the bag.  A slight shake of the bag

[Illustration:  Fig. 2; Homemade Flask]

over the mold will then cause a cloud of coal-dust to fall on it, thus preventing the two layers of sand from sticking, but this operation will be described more fully later on.

The flask, J, Fig. 1, is shown more clearly in Fig. 2.  It is made of wood and is in two halves, the “cope,” or upper half, and the “drag,” or lower part.  A good way to make the flask is to take a box, say 12 in. by 8 in. by 6 in. high, and saw it in half longitudinally, as shown.  If the box is not very strong, the corners should be braced with triangular wooden strips, A A, which should be nailed in, previous to sawing.  The wooden strips BB are used to hold the sand, which would otherwise slide out of the flask when the two halves of the mold are separated.

The dowels, cc, are a very important part of the flask as upon them depends the matching of the two halves of the mold.  A wedge-shaped piece, cc, is nailed to each end of the cope, and the lower pieces, DD, are then nailed on the drag so that they just touch C when the flask is closed.  The two halves of the flask will then occupy exactly the same relative position whenever they are put together.

After the flask is done make two boards as shown at K, Fig. 1, a little larger than the outside of the flask.  A couple of cleats nailed to each board will make it easier to pick up the mold when it is on the floor.

A cast-iron glue-pot makes a very good crucible for melting the metal, which can be either aluminum, white metal, zinc or any other metal having a low melting-point.  This completes the equipment with the exception of one or two simple devices which will now be described.

** Ii — How to Make a Mold [96]

Having finished making the flask and other equipment, as described, everything will be ready for the operation of molding.  It would be well for those who have never had any experience in this line to visit a small brass foundry, where they can watch the molders at work, as it is much easier to learn by observation; but they must not expect to make a good mold at the first trial.  The first attempt usually results in the sand dropping out of the cope when it is being lifted from the drag, either because of insufficient ramming around the edges or because the sand is too dry.