Jul 31

ABRASIVES
In order to remove rust, tarnish or corrosion from metal  of all kinds, when soap and water, oil paraffin mixture, rust removers, metal polishes, etc. have failed or are unsuitable, abrasives are used. In order to get a mirror finish on metal the correct use of die right abrasive is essential. To all intents and purposes, as they get finer, abrasives become polishes. Damaged woodwork can be cleaned and tidied with abrasives, stains and blooms on varnish can be removed; and used in conjunction with paints and varnishes, abrasives help to get deep glossy finishes.
As a general rule, work is started with coarse abrasives and finished with fine abrasives.
There are many different kinds of abrasives, and each
user tends to prefer certain ones; it is not necessary to have
aof them in your workshop. Abrasives can be bought in
loose powder form, as cloth or paper, or in bar compositions for use with buffing tools.
For the purposes of this book it should be useful to describe briefly some of the abrasives and abrasive polishes available. In the various sections, abrasives are mentioned constantly iii respect of specific uses. When working with them, trial and error is the best guide, provided that trials are not carried out on such a big scale that the error becomes irrevocable. After a while an invaluable experience of abrasives and their uses will be built up. Abrasives such as sand and glasspaper, either in sheets or discs for power tools, are used for stripping down and smoothing wooden surfaces, and iii conjunction with paint removers or by themselves, to remove stubborn old paint and varnish. When using sheet sandpaper, glass-paper or emery paper, it call be folded round blocks of wood, or made into sticks by wrapping round pieces of dowelling etc. Discs for sanders on power tools are made in a multitude of grades and qualities, some very rough indeed. Spaced grit carbide discs are excellent for tough work, where scoring of underlying wood can be removed at a later date. Metal discs with tungsten spaced grit over them are almost indestructible and will remove practically anything, but are liable to do damage as well, and should be used with great care.
Sheets of sand or glasspaper are used on finishing power sanders which do not revolve, but work with a fast backwards and forwards action.
Wet and dry emery paper in various grades, so called because it can be used dry or soaked in water as a lubricant without dissolving into pulp, will help to impart a mirror finish to any object which is being painted or varnished. The object is rubbed down with wet anddry between coats until the surface feels perfectly smooth to the fingertips. The emery is used very wet and the lubricating effect of the water helps the emery to cut smoothly without scratching.
Steel wool in various grades is a very versatile material. In rough grades, in conjunction with strippers, it will help to shift paint and varnish. Used with metal polishes it will remove stubborn stuns on metals, and will help chemical rust removers to shift rust. Steel wool pads impregnated with soap are excellent for cleaning greasy metal or wood surfaces. Mirror finishes on wood call be rubbed down with fine steel wool, before waxing to achieve smooth shining but not over
glossy finishes. The uses of steel wool iY1 C011-
junction with wood finishing materials are many, and experience is invaluable. Grade oo or 000 is used for fine work. If you have a polishing lathe with interchangeable mops and brushes, or even if you set up a power drill to take small mops and bobs, you may wish to try liquid polishing compositions. These are equivalent to the bar compositions mentioned below and are intended to be sprayed on to the work as polishing is taking place. This requires special spray equipment so this method is usually only used commercially.
Emery powder, tripoli powder, rottenstone (a mineral found in Derbyshire and mixed with oil), jeweller’s rouge (powdered iron oxide), pumice powder (powdered volcanic lava), crocus powder, carboruriduni, and whiting are all abrasives commonly used in metal finishing, and can be bought in composition bars, either greasy or non greasy, for use with polishing mops and brushes. They are used moistened on soft rags, or on swabs made up on sticks, or on small brushes (old toothbrushes come in handy here).
Obviously care must be taken not to use too strong an abrasive for your particular job. Do not risk making deep scratches which will need even deeper abrasion to be removed, and as polishing proceeds, use finer and finer abrasives until a deep glowing finish is achieved.
ACIDS
Some acids make effective cleaners. They should always be handled with care; rubber gloves must be worn, and the bottles or containers must be carefully labelled, well stoppered, and kept out of the way of children. If you do spill acid on to yourself or your clothing, wash with plenty of clean water and then with water and bicarbonate of soda which is an alkali which will neutralise the acid. When diluting acid, alivays add acid to the water and not vice versa.
Hydrochloric acid. Also known as spirits of salt. Don’t let it get near stainless steel or other metals, except under control, for it will etch the metals. Nor should it touch nylon or any man-made fibres.
Acetic acid. Is the acid constituent of vinegar.
Oxalic acid. A poisonous acid which has many uses as a stain remover. In five per cent solution it will remove ink stains. Two teaspoonfuls of crystals in two pints of cold water will remove blood stains. In saturated solution it will remove black water marks on wood.
Citric acid. A ten per cent solution is sometimes used for stain removing.
Nitric acid. This is a strong fuming acid and if you get will
any on your skin it burn severely. Any slightest amount spilt should immediately be flushed and flooded with water. Skin should be held under a running cold tap. Very diluted, it is used for cleaning gilt and gilding. It can be used to darken soft soldering.
Oleic. Acid in an oily base.
Muriatic acid. Another name for hydrochloric acid. Accumulator acid. Diluted sulphuric acid used in the making of chlorine gas for bleaching.
ADHESIVES
The problems of getting one thing to stick to another have always loomed large for the restorer, especially when the two objects are not made of the same material. Luckily, new types of adhesive have been invented which will literally stick anything to anything. The strength of the stuck joints is also very important, and modern adhesives are so efficient that stuck joins can actually be stronger than any other kind of jour, and where, in the old days the glueing of joins of all kinds was used in conjunction with other fixing methods, dowelling etc., sticking alone is nowadays often sufficiently strong. Adhesives have become so strong as well as water and heat resistant, that it is really no longer necessary to rivet ceramics, and almost totally invisible stuck joints can be made in china. Adhesives mixed with colouring matters, pigments and powders, are used as Hers, thus becoming dual purpose materials (see under Cements and Fillers). Most modern adhesives have many uses and will stick a very wide variety of substances, but some are better than others for particular kinds of work.
Why things stick together is quite involved and difficult to explain. Theoretically, if you can bring two stir-faces together so that they touch all over their surfaces, they may stick together without adhesives. Two sheets of glass will sometimes adhere in this way and become extremely difficult to part. Even two sheets of shiny paper will stick together. I know a trick with a penny, which consists of drawing a coin sharply down a varnished wall surface, and snapping it on with a thumb. The coin will stay there indefinitely if the wall surface is all right. I suppose most of the air is expelled from under the coin, and the rim makes a perfect seal with the varnished surface, and die outside air pressure keeps die coin in place. There was a pub in Potter Heighain in Norfolk, called the Falgate, where the whole surface of die bar surround was covered in coins put there in this way. In fact my father put up the first one. Much later they were all varnished in to preserve them, but eventually the bars in die pub were enlarged and down came die panelling and the pennies. Yet few people would believe that no adhesive was used to keep the pennies up and many of the coins were there for years.
It seems that the function of an adhesive is to make the respective surfaces so smooth that they adhere. When using normal adhesives, as little as is consistent with covering the whole surface should be used, as too much just keeps the surfaces apart, and does not john them together. The john should then be put under pressure and left undisturbed.
All surfaces which are to be stuck together must first be thoroughly cleaned of old grease and glue, or rust, and the adliesive makers’ instructions should be followed carefully. Glues made from gelatine or old type animal glues, can be removed by soaking with warm water. Resinous cements are dissolved by alcohol, celluloid cements can be removed with amyl acetate or acetone. Dissolver will shift modern epoxy resin glues. Once the surfaces are cleaned they should have a rub with sand or emery paper, to make sure all glue is gone, and to give a key for the cement.
Scotch glue. Scotch glue has always been the traditional glue to use for woodwork, and it is still the best glue for veneer work especially where the veneer has to be smoothed or `hammered’ into place with the rounded end of a ball-peen hammer. Scotch glue can be bought either in cake, pearl or powder form. The glue is put into a proper glue pot with water, and left to soak overnight, which makes it swell up and soften. The glue pot is in fact two pots, one within the other. The outside one holds water, the inside one the glue, just like a double saucepan. The pot is put on to simmer and the glue stirred frequently as it heats. Don’t ever boil glue, just get it hot enough to run off the brush when you hold it over the pot, without forming tears. Scotch glue is used hot and is brushed well into the surfaces. It helps to warm the wood before applying the glue. All joints made with Scotch glue should be well cramped or weighted, so that any surplus is squeezed out, and the surfaces brought as close together as possible. Scotch glue is useless for joints or mends which will be exposed to damp, as it will not hold, and in time will even grow fungus. Santobrite call be added to Scotch glue to prevent the formation of fungus. Heat also melts Scotch glue and releases joints.
Durofix. Durofix is a celluloid cement, and is extremely useful as it is transparent, so that it can be built up in layers to form a self-supporting film to repair glass etc. (although acrylic resins have supplanted it for large-scale jobs of this kind). Glass repaired with Durofix won’t stand domestic handling, but for ornamental use it is good enough. One big advantage of Durofix is that it is a one tube adhesive and does not have to be mixed with hardeners.
Et,o-stile. Made in several different types, this is a splendid impact adhesive. Evo-stik Impact Household Adhesive is excellent for joins where the two surfaces may be brought directly together and left without movement until set. Where joins have to be slid together (such as a mortice and tenon joint), this adhesive is not suitable. When using Evo-stik, a coat of the stuff is put oil each surface to be joined, and is left for at least a quarter of an hour. The surfaces are then brought together correctly (no sliding about to get things right), and an immediate bond is made which in time is extremely strong. In fact if you try to break the bond, you may break the wood instead.
Cascattdte is a powder glue which is mixed with water, is good for woodwork, as is
Aerolite which is a powder and a liquid hardener, mixed together in the right proportions for a very strong resin adhesive.
This brings me to the modern epoxy resin two-tube adhesives which are fantastically useful and versatile. There are quite a few makes, and it is not possible to list more than one or two of all the adhesives available in this section, but I think I have mentioned enough to cope with most
jobs.
Plastic Padding. This is a two-tube adhesive and filler, which has a silver metallic colour. It has the advantage of drying very quickly—in ten or fifteen minutes—so that it is useful
will
where speed is helpful. It stick pretty well anything to anything, but its silver colour precludes its use where the join will show, or will not be painted over.
Araldite. In the two-tube pack (A.V. too and H.V. 100), Araldite is suitable for joining any of the materials listed below. All objects to be glued should first be cleaned, the surfaces being thoroughly degreased, then abraded, then degreased again before the adhesive is applied. Also it is important to make sure that surfaces are dry before adhesive is applied, so give them a few minutes in front of a fan heater or on a radiator; or put large objects in an airing cupboard for a while. If there is any paint or old glue on a surface to be joined, it must be removed with a solvent. Dissolver will remove Araldite if it has been used before.
Mix your adhesive on a small piece of glass with a palette knife. Keep some methylated spirit handy for cleaning up, as it will dissolve Araldite while it is still soft. It is important that the contents of the tubes never mix except as and when you want them.
When using two-tube Araldite A.V. ioo and H.V. i oo, warm the two tubes a little before measuring out and mixing the adhesive and it will be thinner, and thus easier to use, but may take a little longer to set.
For china repair Araldite A.Y. 103 and Hardener H.Y. 951 are very suitable because the mixture is thinner; it grips very hard and doesn’t need much pressure to get a good join. Because itis thinner it can be got into small cracks, and it fills all the requirements of unobtrusive adhesion. It is not quite so resistant to water and steam as the two-tube Araldite, so should not be used for repairs to china which is going into domestic use.
All adhesives nixed should be used within an hour as it begins to dry after that time and gets tacky. It is sensible to have a sticking session—collecting together and preparing all the mending jobs you have on hand to do at the same time. It is quite difficult to mix the exact small amount you need for one article and only too ofter, the whole family searches the house for things to mend to use up the adhesive. Left over mixed Araldite will keep in the freezing compartment of your refrigerator for several hours, even overnight, but do not try to keep it there indefinitely or you will end up throwing a useless little hard lump into the dustbin together with the container or sheet of glass to Which it has become firmly stuck.
It is quite simple to measure out the two-tube Araldite exactly because you can squeeze an equal length strip from each tube on to the glass. With the thinner types, measurement is by drops, oreven with two hypodermic syringes— although this would seem to be all expensive way of doing the job. Perhaps it is worth the investment if you are specialising in repairing things with Araldite!
Having mixed the adhesive, spread an even thin coat on each surface of the object, using a match or a rust free nail or a glass rod, and fit the two firmly together. Use gum strip to bind together a join while it dries (see section on Chita). Araldite takes twelve hours to set at room temperature, and three days to harden to maximum strength, but drying can be speeded up by heating, even by baking in a cool oven.
Drying time at 149 deg. C. (3oo deg. F.) 3o rains.
121 deg. C. (zso deg. F.)    i hour
79 deg. C. (175 deg. F.)    3 hours
Do not dry at over Soo deg. F. as at that heat the two-tube Araldite resin darkens.
To join the following materials (all must be degreased before and after abrasion):
Brass: Abrade with emery
Ceramics and Porcelain: Abrade with carborundum and water slurry Copper: Abrade with emery
Glass: Abrade with carborundum
Gold: Abrade with fine emery or crocus paper
Lead, Tin and Solder: Abrade with fine emery
Leather: Degrease with great care. Abrade with glass paper Silver: Abrade with fine emery
Steel and Iron: Abrade with emery
Stone: Abrade with a wire brush
Wood: Abrade with glasspaper
Pastes. Special pastes such as Gripfix, and photographic mounting pastes are most useful for paper work as they do not cause cockling or staining. Some photographic mountains have first to be painted on with a soft brush, and then, when the paste has dried for some minutes, the picture or paper is ironed on to its mount with a warm iron over greaseproof paper.
Paste for paper and leather similar to paperhanger’s paste, proprietary brands of which can be bought, are made up as follows: Recipe i.    lb. plain flour
oz. powdered alum
Mix with water to a cream, and then add a pint of cold water and heat in an enamel saucepan stirring all the time.
When using this paste for leather add a little thin Scotch glue. Keep this paste away from metal before use or it may pick up discolouring stains.
Recipe z. i teaspoonful plain flour z teaspoonfuls cornflour J teaspoonful alum
3 oz. water
Mix all ingredients together well so that there arc no lumps, bring to the boil in an enamel saucepan, stirring all the time, and boil for a minute or two till thick.
Copydex is an extremely useful white, rubber-based adhesive for all fabrics.
H.M.G. This heat and waterproof adhesive is good for some jobs because it is clear and quick drying, but it is not over strong. It can be handled for up to an hour, and goes totally hard in twenty-four hours. It does not slip, and is dissolved by acetone.
AMMONIA
Ammonia is a gaseous compound of nitrogen and hydrogen. It has the property in liquid form of turning grease into a soluble soap and so removing it. Used as a ten per cent solution in water it gets rid of dirt and grease, and some kinds of silver tarnish. It also makes glass and porcelain sparkle. It should never be used on bronze, and can lift varnish on wood. It is in fact, in a strong solution, quite a good varnish stripper (see Stripping).
Scrubbs Cloudy Ammonia is a ten per cent solution.
Ammonia solution is used for cleaning Ormolu (see Ormolu) and in a very dilute form, marble. A few drops added to beeswax and turpentine (see Beeswax) makes effective furniture polish.
ANTLERS
Antlers and horns, mounted on shaped boards—relics of our big-ganic—hunting grandfathers—are quite common junk objects. If it so happens that you do wish to restore such an object, clean the horns as suggested under Ivory and Bone. Fill any holes or chips with epoxy resin suitably coloured with kaolin powder and a little yellow ochre or brown dry powder pigment to match. Stick broken pieces back in place with Araldite, and put a wire core or pin in hollow broken horns, packed round with filler as described in the section on China Mending. The clean horns or antlers should be coated with a light wax polish to improve their looks. The backboard may need mending or completely stripping off, and repolishing.
Antlers which come complete with the deer’s head are more difficult to cope with if the head is in bad condition. A good brushing with Fullers Earth should clean the hair, but the repair of rotted or torn leather sections may be very tricky and take careful needlework. It may be necessary to re-stuff parts of the head. A good mothproofing is always advisable, so spray well with an aerosol niodiproofer, and an insecticide as well, if necessary.

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