There are hut few materials that lend themselves to garden ornaments better than concrete Like stone, it seems to harmonize with the sur roundings and gives a dignified and massive appearance to the whole theme, which is most pleasing to the eye. This ¡s particularly true if good,
bold, graceful outlines are given to the designs of the ornaments used.
As a usual practice, concrete ornaments are cast in plaster or glue molds. If the piece is at all complicated the making of the mold in which it is to be cast is rather an expensive operation, especially so when there are but one or two pieces of the same design to be made.
The author has designed and made several vases shaped as shown in Fig. 34, which have been much admired. The method used in making them is simple and somewhat novel, inasmuch as it embraces a combination of casting and model-
:ng. A description of how these vases are made may be of interest to those readers who are apt at making things and who wish to beautify their lawns or gardens at a minimum expense.
B) closely following the instructions given in the detailed descriptions of the various operations used in the making of the vase illustrated, the
Fig. 35 - Method of Making Outside Moid arid Core
•■i i'^Zajt reader will he able to produce a product equally as good as the one shown.
The iirst thing to do is to make the outer mold, as shown n Fig. 35. This can be made of heavy cardboard or very thin, pliable wood. In the design shown the greatest diameter is 12 inches, therefore the length of the piece of cardboard to he used for mak'ng the outside form must be at least 36 inches long. Make it 38 inches. This k- —«*-■+— I---*-—>
will allow a lap of 2 inches, as shown. The height of the vase is 6y2 inches, therefore the piece should be 38 inches long hy inches high. Form this into a circle and secure the ends by-means of pins or by sewing them together with string. Now cut out a circular piece of cardboard 12 inches in diameter as shown at A, Fig. 35; this is to be secured, by sewing, to the bottom of the outside mold, thus forming a circular box 12. inches in diameter by 6J4 inches high, as shown in the illustration. The next step is to make the k- —«*-■+— I---*-—>
core, or that part of the mold which forms the inside sides of the vase or the hole. By referring to Fig. 36 it will he seen that the core is 6 inches in diameter by 5 inches deep, therefore the piece of cardboard necessary to form the core must be twenty inches long by 5 inches high. This will allow a lap of 2 inches, the same as was given to the outside part of the mold. Form a circle of this piece, as shown at B, and secure the ends in like manner as were those of the outside mold.
Fig. 37—Mold Assembled Read} to Receive Conci '*j
Now with mucilage or glue secure small strips heavy paper to the bottom of the outside of the core, as shown. Then place the core in the bottom of the round box, as indicated in Fig. 35. Locate it over the 6-inch circle, which has previously been drawn on the inside bottom of the box, as shown at A, Fig. 35, and secure it in place by gluing down the small pieces of paper which have already been attached to the outside of the core.
Now fill the inside of the core with dry earth, or, better still, sand. This is done to prevent the
Fig. 37—Mold Assembled Read} to Receive Conci '*j core from collapsing when the concrete is placed in the mold. Before placing the concrete the out side mold should also he bound around with heavy twine, as shown in Fig. 37, to prevent it from bulging. Now msert in the sand or earth, in the center of the core, a wooden plug about inch in diameter, as shown at a ¿n Fig. 37. Taper it as shown, and shellac and oil it well so that it will draw out easily from the concrete. Let it project about 2 inches out from the core. This plug will form the drainage-hole in the bottom of the vase. The mold is now complete, but before filling it with concrete it should be placed on a working-board, which should be at least 18 inches square,' as shown ;.n Fig. 37. The next step is the preparation of the mixture. In this case, owing to the fact that the piece is to be modeled, no stone should be used. The mixture should be composed of 2 parts of good clean sand, not too coarse, and 1 part of Portland cement. Mix the sand and cement together thoroughly while dry until a good uniform color is obtained throughout. Now add enough water to this so as to make it of the consistency of putty or fairly stiff dough. Work it up well so as to procure a uniform consistency through the whole mass. Now place this mixture, in its plastic state, in the mold, ramming or tamping it down lightly as you place it in. Fill the mold flush with its sides, and level it off as shown at A in Fig. 37. Do not disturb the mold, which is now filled with tht mixture, for at least two or three hours. After having set for the above length of time the concrete will be hard enough to allow of the removal of the outer mold, and the sharp corners of the concrete, shown at A in Fig. 38, can be roughly cut off by means of a sharp tool such as the edge of a good strong knife or a mason's trowel. The next thing to do is to make a template, or former, with which to model or shape the vase. This is done as follows: First procure a piece of fairly heavy sheet tin or zinc and draw on it an exact outline of the bottor:, half of the finished vase, as indicated in Fig. 38. Now-cut a piece of i-inch thick wood, as shown, and nail to this the tin template, as indicated. Hold the bottom part of this template firmly to the working-hoard and against the side of the concrete cast, as shown in Fjg- 38, and by gradually working it back and forth around the piece the superfluous cement, which is still a soft state,
will he cut or scraped off of the cast and a good uniform outline will he produced around its entire surface. Now remove the plug a hy means of gently twisting and pulling. Then place another working-hoard on top of the cast, as shown in Fig. 39, at A, and then lift the piece up, at the same time firmly holding the two working-hoards against it, as shown, and reverse the whole into the position indicated hy B in Fig. 39. Remove
the hoard which is now on top, as well as the card board disk which formed the bottom of the mold, and proceed to model the upper part of the cast in the same manner as was expiated for modeling or fornung the bottom of the piece. A detailed drawing of the template to use in modehng the top is shown at A in Fig. 41 It will be noticed that the distance from the bottom to the top of this template is 1 inch shorter than the template used for forming the bottom of the vase. This is to allow for the depth of the ring around the top of the vase, as shown in Fig. 41. The shaded
portion -1 Fig. 39 represents the superfluous cement which i« to be cut away from the top of the cast before starting to use the template to form
Cmssgectmntfirvitgfra-b'. Fig. 42—Mold in which to Cast Handles or Ears attempt to remove it from the working-board for at least eight to twelve hours, for, as yet, it is in a soft state and must be handled carefully.
Cmssgectmntfirvitgfra-b'. Fig. 42—Mold in which to Cast Handles or Ears
First procure a piece of wood and cut it into a triangle, as shown at A m Fig. 42. Make the two sides marked 1 and 2, 7 inches long. Now lay out the outline of the handle on this piece of wood, as shown by the unshaded part a* B, closely following the dimensions given. The dotted lines
on the two ends of the handle show a projection of about J^-i.ich. This length is added to the handle in order to insert it into niches or holes which are later to be cut in the sides of the vase for this purpose. A piece of wood should now be cut out to conform to the outline of the shaded portion shown in Fig. 42 at B This should be made of wood 2 ;nches thick or should be built up of two i-inch boards, as it forms the inner part of the mold for the handles, which are to be 2 nches wide. Securc this piece, by nails, in position on the triangular piece of wood, as shown at C in Fig. 42, and then nail lightly to the outside of the triangle strips of wood as shown, fie sure to have them lap as indicated. The tops of these strips should also he on a level with the top of the solid block a, or a distance of 2 inches from the ■nside bottom of the triangular piece, as shown in the cross-section at D in Fig. 42. Shellac and oil the inside of the mold well to prevent the concrete from sticking.
Now secure four pieces of steel wire 1/8 to 3/16 inch in diameter and from 13 inches to 14 inches long, and bend them to the shape shown by the heavy dark lift« ••) the plan drawing at 7?, Fig. 42. Lay these to one side and then start to till the box or mold for the handle with a mixture composed of the same ingredients as was used for the body of the vase. Fill the mold first to a depth of J/2 inch and tamp or press the cement down well, and then lay in, in the position indicated, one of the wires. Now lay in 1 inch more of the mixture, and press or tamp it down, and then place in the other wire, and fill the mold flush with the top as shown at I) in Fig. 42. Trowel it off smooth and let it set for from eight to twelve hours, so that it will harden up well. Then carefully remove the sides of the mold; first removing side 3 and then side 1. After having removed these two sides the cast of the handle can be easily removed without fear of breaking it. Clean the mold out well and shellac and oil the insides of it again. Then replace the sides 3 and 1 and proceed to cast the other handle in the same way. After removing the handles from the mold wet them down occasionally so that they will become good and hard.
The next step is to cut holes into the body of the vase into which to insert and cement the handles. The sand or earth core, as well as the card board lining, should be removed and a line should be drawn across the top and down both sides of the vase at its center, as shown in Fig. 44. This line will show where the handles are to be located. Hold the handle in its proper position against the side of the vase, and with a pencil outline the position and shape of its two ends on the body of the vase. Now with a hammer and chisel gently cut out holes at these points about inch deep, into
If by any chance there should be any holes or marked irregularities in the surface of the vase these can be pointed or filled up with a mixture composed of the same ingredients as used in the body of the vase. A good smooth, fairly light finish can be procured by rubbing the whole sur face down with coarse emery cloth. Then soak the vase in' water and rub over its entire surface a thiii coat of a mixture composed of 1 part of marble dust and 1 part of Portland cement. Let this dry out and then again wet down the vase. The oftener the vase is wet the harder it will be. Remember that water is a most important factor in all concrete work. One can never get a good bond between two surfaces if the parts arc not thoroughly wet down. The dimensions given in Fig. 3 6 are merely suggestive. The same general principle and directions as given above can be used for making a vase of almost any size and shape, as well as for making tables, pedestals, etc
Glue molds, or flexible molds as they are often called, are extensively used in casting concrete ornaments in which the design embodies heavy relief work containing more or less undercut. Owing to the flexible nature of these molds, they can be made in fewer pieccs than a plaster mold could be made, for the same class of work, and at the same time they can be more easily removed from the cast, while the concrete is still in a more or less unhardencd state, with less fear of injuring the more delicate parts of the design.
The only objection to the glue mold is that its life is limited to from five to eight casts at the most, whereas the life of a plaster mold is practically unlimited. In making a glue mold, as i:i all other cast work, the first thing to do is to procure your original or model of the piece which is to be reproduced. First will be explained how to make a simple one-piece form of glue mold, such as is used in casting pieces similar to those illustrated in Figs. 4?, 46 and 47. Take the model of the piece «fcich ;s to be reproduced, and secure it to the working-board, as shown in the cross-sectional drawing, Fig. 48. A daub of shellac on the back of (he model in most cases will hold it in place on the working-board. Now dampen an old newspaper and lay it over the model. I.et it follow the general outlines of the model as closely as you can, as shown by the heavy line in Fig. 48. The next step is to procure some modelers' clay, and with an ordinary rolling pin roll it out into a sheet about "J4 inch thick. The model is now to
be completely covered with this sheet clay, as shown in Fig. 49, thus producing an even thickness of iA inch of clay all over its entire surface. The clay thus placed on the model is next to be entirely covered with a plaster of Paris case of about,V? inch to I inch in thickness, according to the size of the piece.
The method of casting a plaster of Paris case is explained in detail n the chapter on Plaster Molds. Before cast'ng the case, however, do not neglect to oil the surface of the clay well, so as to prevent it from adhering to the inside of the plas-
ter case. After the plaster case has hardened mark its outline on the working board, and then carefully lift the case and remove it from the clay covering, then :n turn remove the clay covering and paper from the model. If any of the paper should have adhered to the model, clean it off, and then shellac and oil the model well, so as to prevent the glue from sticking to it.
Now take the plaster case and make a good-
sized hole in it at d, as indicated in Fig. 51. I his hole should be at least ^'inch in diameter, as it is to receive the end of the funnel through which the glue is to be poured. Also make a number
of smaller holes, say inch in diameter, at various points throughout the cast, as indicated by the light double lines. These latter holes are
thickness over the entire surface of the model, in order to have it How properly, and also to produce a uniform flexibility throughout the glue mold. The best glue to use in making glue molds is a fine grade of white glue. This can be procured at almost any paint store. If the dealer does not know exactly what you want, ask for the regular grade of glue of which plasterers make glue molds. Almost any good giue, however, will do; it ranges in price from 18 cents to 25 cents per pound. Sheet gelatine can also he used in
it will absorb the water and swell up. Now take a regular double tin; cover the bottom of the inner tin with water, and then place in it the glue prepared as directed above. If a double tin is
not available, two tin pails can be used, as shown in Figs, i ? and 56. One of these should be placed inside of the other as shown, and the bottom of
the inner pail should be kept about 2 inches from the bottom of the outer pail by letting it rest on a block of wood or a piece of brick. When
melting the glue do not have too hot a fire, but let the glue melt slowly until it is of the consistency of thin molasses. When it is of the proper consistency pour it ;nto the funnel, which has previously been secured in place ¡n the plaster
case, as indicated iii Fig. 51. Now as the mold rills up, the glue will run out of the vent holes, which are shown by the heavy dotted lines, thus indicating that the glue "s flowing properly^ As the glue appears at these holes, stop them up with a daub of modeler's clay. Keep on pouring the
glue until it runs out of the highest vent hole and until the funnel remains full. The glue thus poured will take about twelve hours to congeal
or harden, after which time the plaster case or mask, as it is sometimes called, can be lifted oft This is done by first cutting the glue away from the funnel, anil then removing the canvas straps which held the case down on the working hoard and prevented it from rising as the glue was poured. Xow in turn remove the glue mold from the model. This can be easily done, if the model
has been properly oiled, bv simply springing out the sides of the glue cast, and lifting it up from the face of the model.
Before mak'ng a cast in the glue mold, the face of it must be treated so as to make it as near waterproof as one can. A common method of doing this is to paint the surface of the mold with a saturated solution of alum. About three coats of this solution are necessary, letting each coat dry out well before applying the next. A simpler and probahly more effective method is to coat the face of the glue mold with one or two coats of a fine grade of good clear flexible varnish. Before making a cast, always oil the inner face of the mold well with a light oil. To assemble the mold
for a cast, place the mask or case on the working board, as shown in Fig. 60. Then drop in the glue mold, which Will rind its place in the case readily, and then proceed to pour in the cement mixture. The mixture to use for this class of work should be composed of 1 part Portland cement to 2 or 3 parts of sand. Enough water should be added to make it of a creamy consistency or thin enough to pour. Fill the mold with this mixture flush with the top, and then iar the mold up and down two or three times to force
out any air that may have gotten in with the mixture while pouring. If this is not done, air hubbies or voids may appear in the face of the finished cast. Allow this mixture to harden for at least twelve hours after being poured. To remove the cast, turn the case over, and the glue mold will come away from it; then by gently taking hold of the glue mold and bending it up, the cement cast will readily be released.
In making a glue mold for a piece having relief Work on all four sides, or all around its surface, as in circular pieces, such as the table leg, the plaster model of which is shown in Fig. 61, a different method of procedure must be employed than that which has just been explained. The first thing to do is to place the model on the working board, as shown in Fig. 62. Now draw a line along the opposite sides of the model at its widest part, and build up to this line, from the working board, with modelers' clay. Sometimes in order to save clay and time, boards are placed along the sides of the model so as to come almost
to a level with the line drawn on the model, and then the clay is huilt up from these hoards to a line corresponding to the line 011 the model, as
shown in Fig. 62. This line is known as the parting line,".
After having built up the clay around the model as shown, a damp newspaper should be placed over it, and in turn this should be covered with a ¿4-inch layer of clay, as previously explained and as shown in Fig. 63. A plaster case should then be cast over this clay in a similar manner, as explained before and as shown in Fig. 64. After
this case has hardened, the clay and boards, which were used for forming the parting line, should be removed and the whole piece, including the plaster case, the clay covering over the model, and the model itself, should be turned over on the working board into the position shown in Pig. 65. Now the upper part or half of the model, which is still exposed, is to be treated in like manner. Before casting the upper plaster cast, however, :t would be well to shellac and oil the exposed edges of the lower plaster case, so as to prevent the upper half of the case sticking to it. After having cast the upper plaster case on the model, it will appear as shown in Fig. 66.
The whole should then be set up on end, and a
plaster base or bottom should he cast on it. The inner sides of this bottom piece should be tapered and should extend up around the outer sides of the case for at least from 2 to 3 inches, as shown in Fig. 67. The method used for casting a plaster base or bottom of this kind for a mold is clearly-explained in the chapter on "Plaster Molds." After having cast this bottom piece, the whole should be disassembled, and the plaster case, which was cast around the model, should be taken off, and the clay and paper in turn should be removed from the model. The model should
then be thoroughly cleaned up and oiled. The plaster case should then be assembled around it. as shown in Fig. 67, and firmly held together by means of hooks or bands. The glue should then
be poured into the cavity between the plaster case and the mold, as shown in the illustration. After having poured the glue, let the whole stand, without disturbing it ir any way, for at least twelve hours, in which time the glue will have hardened sufficiently to allow of the tivo halves of the plaster case to be removed. These should come away readily from the glue if they have been well oiled before the glue was poured. On the outer part of the glue mold there will appear a line or a slightly elevated ridge of glue. This will indicate the location of the joining of the two halves of the plaster case. The glue mold must be cut along these lines, so as to form two halves of it This cutting can be readily accomplished by using a good, strong, sharp knife. Do not hack :t or roughen the edges of the glue any more than can be helped. The glue mold when cut in halves should appear as shown in Fig. 68. In the illustration one of the halves of the glue mold is shown in place in the plaster case, and the other is shown resting on the other half of the case. By the way it bends under its own weight, one can readily see how flexible it is. After having been cut in half, the inner surfaces of the glue mold should be treated with a saturated solution of alum, or it should be varnished, as previously explained. If the mold is to be varnished, it should be allowed to dry out for twenty-four hours after has been removed from the mode! before, the first coat is applied. It should then be well oiled before a cast is made in it. In assembling the mold for a cast, the two halves of the glue mold should be placed in their respective plaster cases. These in turn should then he
brought together and placed in the bottom part of the mold, then they should be tirmly secured together by means of hands or hooks,' as was done when casting the glue mold and as illustrated in Fig. 67.
The pouring of the cement mixture, the removing of the mold, and the curing of the finished cast is done in a sirmlar manner as when casting
In any other form of mold. In Fig. 69 is illustrated a table, the legs of which are of concrete casts made in the glue mold iust described. The same principles of procedure as explained above are used in making glue molds for round or square vases. The only additional part required for vase work is the core. These can be made of
plaster as described in a previous chapter, or they can be made of glue with an inner core of wood, as illustrated in Fig. 71. In this case the outer part of the inner wood core should be well oiled, so that it can be withdrawn from the glue shell. The glue shell of the core, which will then remain In place in the cast, can then, due to its flexible nature, be collapsed and withdrawn from the inner part of the cast. When casting vases, always cast them with the bottom up, as explained in Chapters III and IV.
When one is through with a glue mold, it need not be thrown away, for the giue in it is still good to use. It should be cut up into small pieces and allowed to dry out. It can then be melted over aga'n and used for making other glue molds. A rack containing pieces of old glue molds cut up, ready for use, is shown in Fig. 5 5, iust above the glue pots and stove.
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