News & Updates:

Like the website?
Recommend Us To a Friend

MAKING PLASTER MOLDS OF TRACKS

1. Carefully clear any foreign matter away from the print in the ground. Then encircle the print with a strip of cardboard and clip or tape the ends of the cardboard wall together.

2. Pour freshly prepared plaster of Paris into the area surrounded by the cardboard walls. It may be difficult to judge the amount you will need, but you will learn with experience.

3. When the plaster has hardened, you can take out the whole piece and clean it off. What you then have is a negative of the print, raised or "in relief."

If you want your cast to be indented, as the track was in the ground, you have one more step; making a positive mold. Brush the surface of the negative mold with soapy water, oil or vaseline.

4. Once again take a strip of cardboard and make a wall around the negative mold. Then pour liquid plaster into the greased mold. Smooth the surface of the mixture with a small piece of board and be sure there are no bubbles remaining. When you have poured in enough plaster to cover the negative mold, let it harden a bit. Then make a loop from a piece of string and embed the ends of the string in the side of the plaster, so that the loop remains on the surface. A few knots at the ends of the string will make it more secure in the plaster. Pour a little more plaster into the mold.

5. When the mixture has hardened, remove the cardboard walls and separate the negative mold from the positive, prying the two casts apart with a table knife. This will be easy if the negative was well greased. Clean the positive well and give it a coat of shellac to help preserve it. If you wish to label the side of the cast, do this before shellacking. Then you can hang the mold by the loop of string.

Related terms include summer activities and camping family california.