RERAMIC STUDIO 
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The tools needed for making the model are the wooden 
board on which the profile is nailed (14) a roll of sheet 
zinc (15), a pair of shears (20), a hammer and box of tacks 
(18-19), a fl a t and half round smooth file, and a small 
wood saw. The outline of the shape to be made is drawn 
on a piece of cardboard and then neatly cut out. The 
cardboard shape is then cut lengthwise in two, the side 
to be used being half of the shape minus half the di- 
ameter of the axle. The cardboard shape is then placed 
on the sheet of zinc and the outline is drawn or scratched 
round the shape on the metal. This is cut with the shears 
and a profile is made such as is shown in sketch 9. (figure 
3). The profile is then finished with the file and sandpaper 
and then nailed to a strip of wood of the length of the bench 
after the wood immediately around the profile has been 
cut away. 
The board with the profile nailed to it is now placed 
on the bench and nailed in such a position that the top 
and base of the profile touch the axle. The bench is now 
ready for the plaster. 
Mixing the Plaster 
Plaster of Paris when mixed with water possesses 
the property of hardening to an absorbent solid. By 
varying the mix and stirring it for a longer and shorter 
period, the degree of hardness and consequently the power 
of absorption is increased or lessened, so that it may ex- 
actly meet the conditions required by the particular pro- 
cess. 
Take a tipped bowl or other wide mouthed vessel of 
ample size, and fill it a little over half full of clean water. 
vShake the plaster through a I inch sieve into the center 
of the vessel. When the cone of plaster thus formed 
reaches the surface of the water very little more plaster 
is needed. Stir vigorously with the hand, and at the same 
time crush the lumps between the lingers, until the whole 
mass appears to thicken perceptibly. 
It is important that the stirring be both vigorous and 
continuous until the plaster eommenes to thicken. 
Forming the Model. 
The plaster is allowed to reach the consistency of a 
thick paste; it is then spread on that part of the axle with- 
in the' profile. Turn the axle slowly while spreading the 
plaster until the shape is clear and sharp. The board 
with the profile may now be taken away and the plaster 
shape left on the axle for one hour, after which time it 
must be lifted out and the shape taken off. 
The two important points to remember in the very 
simple process are that the profile must be nailed firmly 
to the board, and that the wheel must be turned towards the 
top of the profile, thus forcing it to the board and not 
lifting it away and so moving it, as would happen if the 
wheel were turned the other way. The model is noAv 
made and instructions for making the mold will be given 
in the next paper. 
The plaster used should be the best quality obtain- 
able. New York FFF, or dental plaster, may be bought 
for $2.50 barrel of 250 lbs. 
Questions and Answers. 
B. J. M. — I. Where can I buy potters' supplies such 
as clays, glaze and chemicals in small quantities? 
Write to the Department of Ceramics, People's Uni- 
versity, University City, St. Louis, Mo. 
II. I would not advise you to make frit or fire 
pottery in a china kiln. The temperature for firing 
china is about cone 015 and pottery should be fired to 
at least cone 06. While the latter temperature is not high 
for pottery, it is too high for the average china painting 
kiln. 
III. When making frits, I would advise you to get 
the small frit kiln of Caulkins. The frit is fired in a cruci- 
ble until it melts and flows through a hole in the base of 
