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07 31st, 2009| 
Let the repaired piece cool down completely and then soak it in water to remove the gummed strips. There will be some spots of adhesive along the join squeezed out when the jour was made and deliberately not wiped away. Rub the spots very carefully with glass paper and break them down before removing them with a scalpel or a razor blade. This cleaning is quite a delicate operation and if done without abrasion may result in lifting little chips of china or
glaze.
If the crack was also c’., Red and Aralditc with colouring was used, tidy the filled chips with fine glass paper, and over-paint or glaze if necessary.
Moulding aped Modelling whole pieces of a pot or a
figure are missing, the gap can be filled by rebuilding the piece with epoxy resin composition filler. But it isn’t quite so simple as that! Perfectly satisfactory pieces for plates, vases, bowls, statuettes etc. can be moulded or modelled and simply stuck into place provided the piece is not going into domestic use, but such mends are not strong
g enough
to withstand hard wear for very long unless they are sup- ported by metal cores or pins. It is easy to mould or model a jug handle without a core, but unlikely that it will last very long if the jug is used. If the new handle has a core it will be very strong indeed. The making of cores and pins is described in a later section, and here I shall talk about moulding and modelling without supports. The techniques involved are almost identical when supports are incorporated. The job requires only a few cheap tools until the moment when you get involved in metal work and drilling for supports. And many people, once they reach this stage, just take the work to an expert restorer rather than buy drills and bits etc.
Before mending a piece such as a bowl or plate or vase, without using a core, scratch or file the broken edges so that the new piece of moulding will lock into the edge as it sets. The danger is that your new pieces may not adhere too well to the smooth and thin edge of a break without some kind of roughness in which to get a grip, as the problems of adhesion are not quite the same as those of sticking two edges, of porcelain or pottery together.
Next, a backing is necessary. This means a surface up against which you can press the filler to remake the piece. If the object is a flat plate, with : flat surface, the same gummed strip as is used for binding can just be stuck on the outside surface of the piece completely covering the broken area. As it dries it stretches tight and makes a good smooth surface up against which to press the filler. This gummed paper cannot be used on a curved surface because it pulls taut and flat across the curve as it dries. Therefore the mould will
wihave to be made with a flexible material which will take a curve. Plasticine does the job well, but it never sets hard and can be pushed out of shape rather easily. Wedge plasticine before use—this is a potter’s term meaning quite simply banging it until it has no air bubbles in it. A mallet or a wooden rolling pin make good bashers for plasticine.
If you use plasticine for the mould and Araldite for the filler you will have to get some cellulose acetate to use as a parting agent as the two react upon each other and must be separated by coating the surface of the plasticine which will come into contact with die filler.
There are other moulding materials. The dental impression compound Paribar is more expensive, but is quite excellent for the work, and is worth the extra money for it can be used again and again, needs no parting agent, and has other uses. Paribar is softened in hot water before use and resets fairly hard but is flexible enough to be extricated from quite deeply cut castings.
Making Moulds. Imagine that you have to replace a curved piece with a fluted surface, from the edge of a bowl. The whole of the edge of the bowl is fluted in the same way so you take an impression of a matching piece of the pattern oil a sound section of the edge. ‘Wet the surface of the bowl and press a slab of plasticine (about half an inch thick) on to a section just a little larger than the missing piece. Carry the plasticine up over the rim of the bowl so that it will be marked but don’t bend it too far round the rim if there is any ridge or it may be difficult to remove the plasticine without bending it. Press the plasticine well and truly until you are satisfied that you have made a perfect impression. Lift it carefully off and place it over the hole on the outside of the bowl in exactly the right place so that the pattern is continuous. Press it lightly so that the broken edges of the china mark the plasticine, then remove the plasticise, and paint the area inside the edge marks with cellulose acetate parting agent, then replace it over the hole. It will stick to the dry china round the edges of the break. Bend over the top sections of plasticine away from the hole, round the rim of the bowl to keep die mould in place. A few strips of Sellotape across it and on to the china will help. Don’t use gummed strip, for this will dry out and flatten the mould. The Scllotapc may give slightly but will help to avoid the disaster of the mould coming off the pot in the middle of die filling operation which follows.
Paribar can be used in exactly the same way to make a mould especially where there is a deeply indented pattern in the china. The Paribar goes hard, but it can be softened with swabs of boiling water and removed from die filler section without breaking it when the job is done. No parting agent is needed so that the Paribar can be put directly on to the break and left there.
Filler Composition and Filling. Now to mix up sonic filler (see Fillers and Cements). Araldite two-tube epoxy resin is first mixed together and then titanium dioxide (or other whitener) is added until the mixture has a nice doughy consistency. This mixture is a bit sticky and clings to tools and fingers. Keep a little dish of the powder handy, and another dish of Methylated spirits. Dip your fingers in the powder, and the tools in the Meths from time to time, and you won’t get so stuck up. When dried out this filler looks exactly like biscuit, or unglazed baked china and takes overpainting very well. It also sticks directly to the edges of the break and you should have no trouble in making a perfect join. It isn’t the easiest of jobs to make and handle this filler, but the result is so good that it is worth practicing to get the mixture of the right colour and consistency.
Kaolin mixed with Araldite in the same way makes a very stiff, not quite so sticky, more translucent and buff coloured filler, but it has the disadvantage of not sticking quite so well to the edges of broken china as does the first mixture.
Isopon polyester resin filler is a paste which is mixed with a hardener. It is excellent for filling big holes as it dries quickly, but this means also that you must be able to work quickly. When using Isopon make all inside mould of the break as well, and having filled the mould, put the second inside mould oil to the filler from the inside to get a smooth interior surface, pressing it down well. Isopon requires no parting agents. Although it will stick to itself so that it call be built up in layers, it will not stick to china, so when the moulds arc removed, the new Isopon piece will come away and will have to be stuck in just like an ordinary broken piece. It can be rubbed and filed to finish it off It cannot be used as an adhesive.
Bondapaste is another excellent filler which hardens quickly and does not have to be baked, nor does it require powder additions to make it opaque. It does not dry white, but this is immaterial if you are going to overpaint it any-way. It can be used as an adhesive or cement and when used as a filler it stays in place without further adhesives. It can be filed, carved and abraded within a quarter of an hour of use, so is a very time-saving material, once one is experienced enough to shape it quickly.
The exact consistency of any filler is difficult to describe and can only be discovered by trial and error. If it is too hard it will push the plasticise out of place as you press it into the mould. If it is too runny it will tend to run into the lower part of the mould in whichever place you are holding it, and will not make a piece of even thickness. If the mould is made of Paribar then a stiffer nix of filler can be used.
The mixture is worked into the aperture with a round ended tool. Boxwood potter’s modelling tools are excellent but many things make good modelling tools. Some workers like to prop the pot up as they work, others hold the pot in one hand so that the break with its mould is cupped and held in position while the filler is worked in. Great care must be taken to make sure that the filler goes into all the corners and crevices right up to the edges, with no air bubbles trapped underneath. Smooth the inside surface with the tool and with thumbs and fingers until it is as like the surrounding inside surface as your eye can judge. Setthe pot aside for an hour, if the filler is Araldite, by which time it will have set to a rubbery consistency and can be worked further if necessary. If a quicker setting filler has been used, once it has set hard it can be carved, filed and abraded until it is absolutely perfect, and it is then ready for overpainting.
To speed up the setting of a mend done with Araldite, bake the pot for half an hour at zoo deg. F. If there are any small cracks or pits in the surface fill them with a thin mixture of filler, using a water-colour brush.
Chips. The mending of chips, big and small, which do not go right through a piece, involves work which is halfway between the filling of apertures as described above, and modelling
which is described in the next section.
Quite simply, you make up a mixture of any of the above mentioned fillers into a fairly stiff mixture and press it into the previously cleaned and dried area of the chip and smooth it until it looks right. Don’t get air bubbles under the filling. Wheel chips—large chips on the edge of a piece—should first have a thin layer of adhesive, to help bind the filler in place. The art of filling chips is to get a good blend along the edges and to get the filling neither too proud nor too shallow, and in getting the composition in so that no air bubbles remain behind to raise it in due course. If you suspect that a little air is trapped, prick the filler with a pin and press it down again and fill tip the pin hole.
Allow the filler to dry out over a hot radiator and then, when it is hard, rub it down with glass paper until you are satisfied that the chip, after overpainting, will be indistinguishable. Pick up the piece and squint at it at eye level in all possible planes, and rely on the sensitive tips of your fingers run across the mend to detect any irregularities. If even at this late stage the chip is not properly filled, more composition can be added for it will stick to itself, and the process repeated until you are satisfied.
Modelling. When neither straightforward sticking, nor press moulding can be used to mend an object, try modelling. It is impossible to make a mould for a missing piece which is not a repetition of another part of the object, as described previously. The missing piece just has to be built up from scratch and the result depends on the artistic ability of the restorer. Large modelled sections will have to have metal supports—dowels, or pins, or strips—and the techniques will be described later on. I am still concerned with the techniques which do not include drilling.
When a part of a plate, or a vase, or perhaps a lid knob must be remodelled, take a piece of rather doughy filler composition and roll it either flat for a flat section, or into a ball for a knob, or into a sausage for a handle, in an approximate size and shape for the job. Then press it firmly to the edge of the broken part, and model it with Boxwood tools, fingers and any suitable home made tools that you may fancy. Whenever epoxy resin mixtures are being used, dip the tools in methylated spirit to avoid sticking.
Modelling becomes really interesting when a porcelain object such as a figure or perhaps a vase festooned with flowers and leaves has pieces chipped out or broken off and lost. To remake flowers and leaves is not at all difficult. Any woman who has ever made an apple pie with a decorated crust knows the technique. The pastry, in this case filler composition in a nice doughy mixture, is rolled out to the thickness of the petal or leaf required and then pieces are cut out of it in the flat. A small sharp knife or scalpel can be used as a cutter, shapes having been first marked out with a darning needle or a fine graver. Or, if the leaf or petal pattern is to be repetitive, a cutter can be made out of strip brass or copper foil, beret to make the appropriate shapes. Make a template or pattern out of plywood, using a fretsaw (see Fig. 8). Tack this pattern to your work bench with a central nail and then hammer a copper foil strip round it with a small hammer until it is exactly the same shape. If the template is pinned with a central nail it can be pivoted round as the cutter is being made so that all pieces can be reached.
The cutting of different species of flowers, daisies, roses, apple blossom etc. is hard to describe exactly. It is a matter of careful observation of thepetals which are to be matched, and of measurements with calipers and dividers, if your eye is not good enough. Petals are cut out in flat shapes and bent over slightly at the edges, and rolled into concave shapes etc. Once your petals and leaves arc made they are then fixed to each other and to the main piece, and there is no great difficulty about this unless the anchorage point is very small indeed, especially if you arc using a good adhesive filler composition such as Araldite and titanium dioxide. it is often possible to add an extra leaf, or to put in
small
a smasupport of composition disguised in some way as part of the decoration, which will hold the modelled part in place. Most people have a collection of tools for modelling which they have made specially to get into different corners ; sewing needles, bent knitting needles, scalpels, spatulas, rifflers, spikes and blades of all kinds, even old hacksaw blades, conic in usefid.
When pieces of an object are missing for which no pressed mould can be made, it is still possible to make a mould out of plasticise which approximates pretty closely the missing piece, and to put this on to the whole in such a way that the aperture can be filled with composition in exactly the same way as a pressed mould is filled. Then the new piece must be rubbed and shaped to final perfection after the setting or baking process has been completed; but
this can be a slow job.
There are problems when it comes to modelling difficult things like faces; it rather depends upon how clever you are, but there is yet one more way, which involves modelling. It is a much more complex and tricky job, but it can save such a lot of time and trouble in the long run, -aid once again may enable you to get away with it without resorting to pinning and dowelling.
Make a model, in plasticine, of the missing part. Actually this is easy if you have a talent for modelling, terribly difficult if you haven’t. Say for instance that half a leg and a foot are missing from a figurine. Using calipers and dividers, measure the other leg and foot exactly, so that at any rate lie won’t have a size six left boot and a size ten right boot. Then model a plasticine leg to the right diniensions and in the kind of position in which it looks as if it ought to be, and keep trying your model in the space until it satisfies you. Plasticine doesn’t harden so take as long as you like over making the model.
Having made your plasticine model, a mould must be made from it and a cast or pressing taken from the mould. The finished cast can simply be stuck into position (or dowelled or pinned if necessary).
Take a sheet of glass, and a large lump of plasticise. Roll the plasticise out into a very thick strip and lay it on edge on the glass (see Fig. 9) in a square or a circle plenty big enough to hold the model, horizontally. Then fix the model, horizontally, halfway up one side of the container that you have just made. A peg carefully inserted into the end of the model and pushed out through the container side should hold it into position. Then prepare some plaster of Paris. Into another container which can be handled easily and has a pouring lip, put enough water to half fill the mould container, and sift plaster of Paris powder into it until the mixture is the consistency of thick cream, stirring with the hand to break up lumps. Then pour the plaster of Paris mixture into the mould until it is halfway up the model. Leave the whole thing to set. Then cut two wide grooves or shallow holes out of the plaster.
sure that it is really well drenched and that no tiny part has escaped swabbing. This acts as a parting agent between the two halves of the plaster mould. Make another mix of plaster as before and pour this nito the mould until the model is well covered. When this has set, remove the plasticine case and case the two sections of the casting apart. Take out the original plasticine model and you should have a perfect mould in two halves. This mould will have two locking pieces where you cut the grooves or shallow holes so that when the two halves are put together again they will locate exactly, and at the end where the model was attached to the side wall of the plasticine container, there will be a hole.
Now you have a mould which can be used to make a casting or pressing of your original model. Smear a film of silicone grease all over the pattern sections of the mould to prevent the filler sticking to the plaster of Paris, and then make up enough filler composition to fill the two halves of the mould. This filler should be soft enough to flow freely into the mould sections. When the two sections are filled, bring them together and bind them tightly with wire. Ram the composition well home, through the hole. Leave the mould, with the hole at the top, for two hours to set, and then, if you are using epoxy resin, bake it for half an hour at 2oo deg F.
Undo the wire binding and take off the plaster. If you have not used a parting agent, the plaster can be cut out and broken away and the last of it scrubbed off the model. Stick or dowel the finished model to the whole, having
made sure that the edges fit perfectly by filing and abrading. bradin,
Any discrepancy in fit which is too big to be put right by filing, can be filled with some filler composition.
Moulds can also be made from pieces of porcelain similar to the piece you are trying to replace, and then pressings made from these can be carved, filed, abraded, and built up to fit exactly.
Instead of plaster of Paris, rubberised solution such as Qualitex can be poured around your model. The advantage of using this material is that the mould is flexible and will come off difficult undercut models without damaging them. Rubberised solutions, therefore, are best for making moulds from models which must not be damaged in any way. The technique is much the same as that described above. A plasticine container is built up round half the part to be copied, and the solution is poured in.
The process is repeated on the other half and you then have the complete mould in two sections. Details vary with each job.
Faces on statuettes are very alike, and differ only iun detail of hair and headdress. There is no reason why, if you collect figures, you should not make a series of moulds or masks from any statuettes that come your way, and so build up a stock of faces iii reserve for the day when they may be needed.
Incidentally, the principles of making casts, moulds, pressings etc. are generally similar for work in all kinds of materials, and many restorers of objects other than china, such as old guns and pistols, make their own metal castings. It is a skill which has so many applications, not only for restoration but for creation. Modem materials make exciting castings and pressings, and it is an art well worth studying for its own sake.
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BAMBOO FURNITURE
Bamboo furniture (hall stands, tables etc.) is rather rickety, and repairing it is rather a matter of careful gglucing and dowelling. When a piece of bamboo has been badly broken it will probably be a splintery split rather than a clean break. A wooden rod or dowel inserted through the Huddle of the bamboo will strengthen it so that you can tidy up the break and stick the splinters down again (see Fig. 4). The hollow bamboo is blocked at each ring and a hole will have to be bored right through so that the dowel can pass along. If you don’t possess a long enough bit, a red-hot iron or steel rod will burn a hole through, but be careful not to set die whole thing alight.
If the splintering is so bad that a lot of it has to be removal, tile piece can be built up again with Araldite suitably coloured, either yellow ochre or mottled brown. A good cleansing furniture polish will bring up the bamboo to a good shine, but epoxy resins don’t polish well.
want a permanent waterproof finish, clean off the bamboo thoroughly with a solvent to remove any old wax or polish; then wash and dry it and paint or spray the bamboo with polyurethane varnish or glaze such as konscal Hardglase or Translac.
BAROMETERS
If a barometer needs to be repaired, it is best to take it to an instrument repairer, but the cases themselves were often beautifully made, and quite worth using for some other purpose. The case of an aneroid barometer with the works removed might make a good frame for a small mirror, or, filled in with a suitable piece of wood, a base for any kind Of object, such as a ship model.
BASKET WORK, CANEWORK, WICKERWORK, RUSHWORK
All kinds of furniture incorporating these materials turn up in junk shops. They arc often in quite reasonable condition except for the grime of years ingrained in all the cracks and crevices, and for discolouration and fading.
Deal with the stuff in the garden on a warm sunny day by washing it very thoroughly with soap and warn water on cotton wool or a soft rag. Then dry it well and leave it in the sun for several hours, and the sunlight will bleach the basket work. Wickerwork chairs won’t hurt by being lightly scrubbed with cold salt water and will bleach quite a bit in the sun. Very dilute domestic bleach will whiten these materials without damage.
Stick together any pieces which have become unravelled with Evo-stik, and the following day, polish the chair with a silicone furniture polish or cream. To make a semipermanent protective skin apply a thin solution of acrylic resin such as Technovit, or a clear polyurethane glaze. These coatings will prevent dirt from getting at the wicker again, and will bind any pieces which tend to split or flake apart. The surface will be glossy, but because it is broken won’t have the over-bright mirror effect that these glazes give to plain wood.
To preserve wickerwork without glazing it, apply a paint of white beeswax dissolved in benzene (see Beeswax).
BATTERSEA ENAMELS
Genuine Battersea boxes, snuff boxes, trinket boxes etc. are rare, and are made of copper surfaced with opaque glass decorated by hand painting or by transfer painting. Any kind of small decorated box which turns up in a junk shop is liable to be labelled Battersea, and probably isn’t. As to cleaning and repairing such items, a wipe with a squeezed-out soap swab, a thorough drying, and then a rub over with Renaissance wax should do the trick. Don’t use solvents in case non-synthetic glues have been used.
BEADWORK
Beadwork was once quite a popular art, and 19th-century young ladies seemed to have spent a lot of time at it, making purses, book covers, tea cosies and even ambitious things like screens. A wash in warm soapy water is about the best way to clean it, but dry it immediately and carefully in case there are any metallic beads which might rust. Repairs are a matter of good needlework. Some of the beads won’t pass a needle; in this case use nylon thread which can be pushed through. To stiffen the tip of the piece of thread, dip it in a little melted candle grease and roll it between your fingers.
