Success Guides

Successful BasicConservationA do-it-yourself guide

Helping Heritage OrganisationsProsper

Success Guides

Successful BasicConservationA do-it-yourself guide

Jane Thompson Webb

Front cover picture: Agitating ingrained depositsand stains on a copy of John Bunyan’s ThePilgrim’s Progress, 3rd edition 1679, held at TheJohn Bunyan Museum & Library and for whichthe museum was recently awarded £5,000 fromthe AIM Conservation Grant Scheme, supportedby The Pilgrim Trust.

Helping Heritage OrganisationsProsper

1. Introduction

The term ‘conservation’ can be used inrelation to museums and the naturalenvironment and it can be difficult toknow what is meant by the term.

In museums, there are two approachesto conservation. One is preventiveconservation or collection care, whichtries to manage various factors toprevent or reduce the effects of decay on a daily basis. The other isinterventive conservation, which is theprocess whereby objects are stabilised,cleaned or supported to ensure theirsurvival and to make themunderstandable, without removing theevidence of their past life. This guide isconcerned with interventiveconservation.

Who should do the work on an object?It depends on the task. The naturalchoice is a conservator, preferably onewith professional accreditation throughthe Institute of Conservation (ICON).Unfortunately, many museums havevery little, if any, budget to spare forconservation. This guide aims to leadyou through the conservation that it issafe for you to carry out yourself and tohelp you decide when to use aconservator.

2. Assessing an Object

Before carrying out any work on anobject, or indeed, determining if anywork is required, it is very important toassess the object. This will enable youto get to know the object and establishits condition. You should be able todetermine if the object is dirty ordamaged and if any work has beencarried out previously. This is a straightforward procedure, but it is one that

requires a little time. You may like todevise a tick sheet to help you thinkabout the same criteria to check eachtime. Such an assessment can be usedfor objects entering the collection orfor those going on loan.

At the end of the assessment youshould have established if it isappropriate for you to carry out thework or if a conservator is needed.

• Before beginning the assessment,refer to the object’s previousdocumentation as this should show ifany work was carried out in the pastand what condition the object was inwhen it arrived at the museum.

• Prepare a suitable work space andwork in good light so that you cansee the entire object clearly.

• Think about the handlingrequirements of the object. Can itsupport its own weight or does itneed support from tissue paperscrunchies, plastazote, book cushionsetc? Can you move and lift the objector do you need someone to helpyou? If you have to move the objectto examine it, make sure it is packedproperly so that it does not getdamaged in transport.

• It is recommended that you weargloves when handling the object. Itmay be dirty, contaminated, or havesharp edges so protecting your handsis important. If it is a large, heavyobject wear rigger-type gloves. If it is a smaller object such as a tool,advertising sign or toy, wear thinnergloves. Many museums now usenitrile gloves in preference to cottonas the fit is better and they givebetter tactile abilities. They alsodon’t catch on rough or loosesurfaces. If the object has avulnerable surface e.g. white marble,

3 AIM Success Guides

Successful BasicConservationThis guide is a companion to the Success Guide,Successful Collection Care. Together they provide apractical foundation to understanding ‘preventive’ and‘interventive’ conservation of our collections.

This guide aims tolead you through theconservation that it issafe for you to carryout yourself and tohelp you decide whento use a conservator.

polished metal, gilding, lacquer, inlayetc, wearing gloves will protect theobject from your hands. Finger markscan etch into metal surfaces andstain other materials.

• Look at the object as a whole – is itdirty, broken, corroded, cracked, pestdamaged, deformed? Are partsmissing?

• Look at these areas more closely andbe specific about what the damageis. Avoid using general terms, such as“fine” as it can be difficult toremember exactly what the term wasmeant to mean when the object islooked at again. Use simpleterminology to describe the damagesuch as “handle missing” or “crackedon right side”. This means that thereis no confusion over what you arerecording.

• List all the kinds of damage, even ifthe areas are very small – includehairline cracks and spots ofcorrosion.

• If the object is made from differentmaterials or different parts, try tolook at each material or partseparately. Remember to lookunderneath and inside the object. Atorch can be useful for this.

• Record what you see. Draw a sketchto show where the damage is orannotate photographs. Digital imagesare particularly helpful for this.

• If the object is in excellent conditionthen state this, but specify that thereis no damage at all.

Having assessed the object, you thenneed to decide if there needs to be anyaction. The future use of the object willinform the treatment. If it is going ondisplay you may want it to look its best,whereas if it is staying in store ensuringthat the object is stable may beenough.

If the object is dirty but otherwisestable you may decide that you don’tneed to take any action. If youconclude that the damage is likely toget worse or if the object is difficult tounderstand because of the dirt,distortion, damage etc, then some kindof conservation is probably needed.

How much may depend on what isgoing to happen to the object and thebudget available.

Any conservation should retain thehistory of the object, should notremove any surface finishes or parts unnecessarily and should be removable.

No treatment is fully reversible and it is not always possible to return theobject to the state it was in before thetreatment occurred, e.g. one can’t putthe dirt back! It should, however, bepossible to remove the treatmentwithout causing damage to the object.

Do bear in mind that improving theenvironment, storage or support maybe more beneficial than hands-onconservation.

3. Using a Conservator

After assessing your object it isimportant to decide whether toattempt the work yourself, or to use aconservator. If the work is beyond yourexperience or confidence or will takelonger than the time you have available,then a conservator is necessary.

Conservators usually want to giveobjects the best treatment possibleand although this will undoubtedly givean excellent end result, it may not bewhat you require. Give the conservatora detailed brief of the end result youwant and ask them to break down theirquote into options – this will allow youto select the treatment that you wantand can afford. Don’t be afraid to keeptalking to the conservator – they wouldrather spend time doing that and havea happy client. That way you are morelikely to use them again!

4. Health and Safety

Not all conservation involves usingchemicals, but there are a range ofcommon ones that even non-conservators can be confident of using.The next section details some commontreatments. It will introduce a range of

Collections Successful Basic Conservation 4

No treatment is fullyreversible and it is notalways possible toreturn the object tothe state it was inbefore the treatmentoccurred.

common conservation materialsincluding solvents and chemicals thatfall under the Control of SubstancesHazardous to Health Regulations(COSHH) 2002. All solvents andconservation materials are potentiallyhazardous. A material safety data sheet(MSDS) should be obtained at the timeof purchase. They can be found on theinternet if they are not supplied, e.g.for products that can be purchased insupermarkets and water, by searchingon “MSDS” and the name of thesubstance. The MSDS should be usedto create a COSHH assessment. Theseassessments show you how to use thematerial safely and how you can limitthe risk posed by the material to yourhealth.

There are some basic rules that youshould follow when dealing withsolvents and chemicals, e.g.

• You should wear gloves whenhandling materials and wear asuitable face mask for dust orsolvent.

• Work in a well ventilated area andideally don’t use offices or tea roomsso that colleagues are not exposed tothe fumes.

• Wear an apron or lab coat to protectclothes, tie back hair, remove large ordangling jewellery.

• Ensure that the feet are adequatelyprotected. Open-toed sandals arenot a good combination withconservation.

Keep solvent bottles etc closed andonly have small amounts present onthe work table. Make sure that you useappropriate containers – coffee jarsdon’t have a good seal, glass bottlesand jars designed for oils and pickles orchemical bottles are best - and labelthem clearly. One colourless solventlooks much like another.

Note that any material used in a workcontext needs an MSDS and COSHHassessment. This includes water andeveryday materials such as washing upliquid. This may seem odd, but it is justto ensure that the work environment issafe for everyone.

5. Basic Treatments

If you decide to undertake a treatment,it is important to remember that if youfeel unsure in any way during the

5 AIM Success Guides

Dusting is carried out using a lint-freecloth, ideally micro-fibre. Fold it tomake a pad to fit the palm and cleanusing flat wipes, in the direction ofthe grain if there is one.

process, you should stop. If the objectseems weaker than you thought itwould be, if you find that you aren’tconfident about continuing or if youhave concerns about the treatmentyou have selected, stop and seekadvice. It is better to be safe than sorry.

Cleaning

Cleaning will often produce a dramaticvisual result and may be all the workthat is necessary. It can be brokendown into two main types:

• Dry methods that use dusters,brushes, vacuums and smokesponges. These remove dirt and dust.

• Wet methods that use detergents,water and other solvents. Theseremove dirt that has adhered to thesurface and cannot be removed bydry methods.

• In addition there is polishing, whichcan use wet or dry methods toremove corrosion to develop a shine.

Note that all the cleaning methodsdescribed in this guide are surfacecleaning methods. Immersion methodsshould only be carried out with theguidance of a conservator.

Always test the method you select in asmall, inconspicuous area to ensurethat the object can physically withstandthe cleaning and that the cleaningdoesn’t damage the surface.

Always begin with dry methods.

Dry methods are usually least likely tocause further damage to the objectand can be incorporated into regularhousekeeping programmes.

Dusters should be lint-free so that theydo not leave fibres on the object orcontribute to dust in the space. Thebest duster is the micro-fibre cloth.These have a slight static charge thatattracts and holds the dust.

Useful for:• Removing dust from smooth surfaces

and is a quick and easy way of doingso.

• Cleaning objects on display,particularly the horizontal surfaceswhere dust collects.

Method of use:Fold the duster into a pad about thesize of the palm of the hand. Place theduster onto the surface and clean usinga flat wipe from one side to the other.Do not use a circular motion as thismay lead to circular scratches. Straightscratches are less visible. Keeprefolding the duster so that you arealways using a clean area.

Once dirty, dusters should be washed.They may be hand washed in a milddetergent, such as Stergene or Woolite,or in a washing machine. Thetemperature of the wash is notimportant, nor does it matter whetheror not fabric softener is used. It is bestto avoid biological washing powders orliquids as traces of enzymes can beretained on the duster; these can bedeposited onto objects and may causedamage to occur.

Brushes are used where the dirt ismore ingrained into the surface, if thesurface is rough, made of textile or if ithas a lot of undercuts. It is usually agood idea to use brushes made fromnatural bristle as this generally doesnot scratch. Hog’s hair and pony hairare the types most commonly used. Itis useful to have several brushes ofeach type of bristle and brush type asthey can be used for different materialtypes and different jobs, e.g. brushing aframe or brushing a stone sculpture.

Useful for:• Cleaning objects with moulded or

carved decoration.• Cleaning rough or delicate surfaces.

Method of use:• The ferrules of brushes (the part that

holds the bristles) should be boundwith masking or insulating tape topad them so that they can’t scratchor damage the object.

• Brushes should be labelled with amaterial type (wood, metal, paperetc) and they should only be used forthat type of material. This avoids

Collections Successful Basic Conservation 6

Immersion methodsshould only be carriedout with the guidanceof a conservator.

damaging an object by scratching itwith particles from another materialor depositing dirt onto anotherobject. Bristle type should bematched to the material to becleaned. Hog’s hair is stiffer thanpony hair and is thus more suitablefor robust surfaces.

• Dust from the top of the objectdownwards.

• Use a gentle sweeping or flickingmotion to lift the dirt off and awayfrom the surface. Brushes are usuallyused in conjunction with vacuumcleaners as the brush lifts off the dirt and the vacuum removes it.

• Brush along the grain (if there is one)to lift dirt out of the crevices.

• Brushes should be washed after use.Use a mild, liquid, detergent, such asStergene or Woolite. Massage thedetergent into the bristles and rinseunder a tap. Allow to air dry.

Vacuum cleaners are used to removedust from an object or room. They canbe used in conjunction with brushes oralone with the vacuum cleanerattachments.

Useful for:• Taking dust away• Cleaning objects with moulded or

carved designs in conjunction withbrushes.

• Cleaning textiles.• Cleaning rooms or galleries.

Method of use:• Vacuum cleaners for general cleaning

and object cleaning should be keptsolely for their separate functions.

• Vacuum cleaners used for objectcleaning should have variable suctionand this should be used at its lowestsetting initially until you are certainthat the surface is robust enough towithstand more suction. Vacuumsdesigned for museum use areavailable from conservationsuppliers, but variable suction can beadded to most vacuums by asking avacuum cleaner engineer to fit apotentiometer.

• If used with brushes the vacuumcleaner is used only to catch thedust. The vacuum cleaner should beused without attachments and theend of the tube should be held closeto the brush so that the dust can beswept into it.

• Net, gauze or a piece from old tightsshould be fixed over the end of thetube with a rubber band to preventany pieces of object that may becomedetached from being sucked into the vacuum bag. The net will needcleaning periodically – remove it andeither pick the dust off or carefullyvacuum the net/gauze and thenreplace it. The end of the tube can bepadded with plastazote or polyesterwadding; this is particularly importantif the object could be damaged by

7 AIM Success Guides

Brush labelled with material andpadded ferrule. Brushes help toremove dirt from rough surfaces. Toensure that objects are not damagedby fragments from other objects,label brushes with material typesand only use them for that material.The metal ferrule may scratch theobject. To prevent this, pad it withmasking or insulation tape.

Collections Successful Basic Conservation 8

bumping into the tube. Care shouldbe taken not to place the vacuumbody on the object as this may crushor otherwise damage the object.

• Ideally, textiles should be vacuumedthrough a screen to prevent suckingup loose fibres. The screen can bemade from stiff net or fly-screenmaterial and the edges should bebound with masking tape or tackedto a wooden frame.

• If used with the vacuum cleanerattachments care should be taken toensure that the object can withstandthe force applied through theattachment.

• Begin cleaning with the lowest suction,only increasing if the object is robust.Floors, walls and ceilings can becleaned using the floor tool. Takecare as some floor tools have wheelsand these can mark painted surfaces.

• Upholstery, furniture, curtains androbust textiles can be cleaned usingthe round brush end.

• Be cautious with both of theseattachments as it is all too easy tosuck up all or part of the object –damage may not be obvious.

• The crevice tool can be used to cleanthe gap between floor and skirtingboard and inside ventilation grills.The flat upholstery tool may be used

on robust textiles but do check forloose pile or fibres. Care should betaken to avoid bumping the vacuuminto objects.

• Vacuum cleaners should be washedout periodically, including all thehoses and attachments to ensurethat dirt and insects are nottransferred to other objects or areas.

If the dirt seems to be bound moreclosely to the surface then methodsthat come into closer contact with theobject may be effective.

The following methods can be used onstable surfaces such as stone, plaster,unglazed but not powdery ceramics,tiles, paper and wood including non-powdery polychrome:

Smoke sponges are spongesimpregnated with chemicals that act as a dry detergent, bonding with andremoving dirt. There were originallycreated to remove smoke deposits.These are not the same as ‘magicsponges’ advertised for domesticpurposes, which have to be wetted inorder to use them.

Useful for:Removing dirt that is bound to asurface but where solvents maydamage the surface.

Vacuuming with a net over the endof the tube. Vacuuming is a veryeffective way of removing loose dirt.To ensure that any loose fragmentsof the object are not sucked into thevacuum, cover the end with net.

Method of use:Cut a small piece from the smokesponge. Use it dry and gentlyrub/stroke it over the dirty area. Becareful to support the object so thatcleaning does not tear or wrinkle theobject. Rotate the piece of sponge as itgets dirty and wash after use. They canbe reused several times.

Erasers can be used in the same way assmoke sponge, but should only be usedon hard surfaces or robust paper. Theplastic erasers are the most useful –natural rubber may mark the surface.

Wet Methods

If dry methods do not remove muchdirt or there still seems to be dirtbound to the surface, then wetmethods may be more effective. It isimportant to note that these methodsdo have some dangers attached.Surface coatings may be removed,colours may bleed and corrosion maybe activated.

Test your solvent on a small,inconspicuous area first. Wait for thearea to dry completely and then assessthe surface. If there is any clouding,

discolouration, colour movement,removal of any surface coatings orother negative changes, do notcontinue. Remember, you cannot putback what you take away.

Paper, oil paintings and textiles shouldnever be cleaned using a wet methodunless the work is to be carried out or directed by an experiencedconservator. Plastics should not becleaned with any solvent other thanwater, and should not be wet cleanedat all if the surface is sticky.

Wet methods refer to all techniquesthat wet the surface. Water and othersolvents can be used in combination orsingly and can also be used with orwithout detergent, ideally a non-ionicdetergent. Conservators generally useSynperonic A7 but any mild, non-biological detergent can be used, suchas Stergene or Woolite.

Think carefully about the end resultyou want before you start the cleaning. Cleaning a small part of anobject will often leave an obvious linebetween cleaned and uncleaned – itmay be better not to use wet methodsrather than have something that looksodd.

9 AIM Success Guides

Cleaning with a smoke sponge. Dirtthat cannot be wet cleaned mayrespond to a smoke sponge. Usedlike an eraser, it can be used untildirty and then washed for reuse.

Be careful not to over clean. Over-zealous cleaning may remove theoriginal surface finish and may leave anobject that no longer seems to behistoric. Your visitors want to gain asense of history in the collections onshow, so try not to eliminate thiscompletely.

The following solvents are those mostcommonly used in conservation:

WaterThis is the most widely used solventand solvent testing should always beginwith water. It is a much strongersolvent than is generally appreciatedand will remove or lessen most dirtdeposits. It’s a good idea, wherepossible, to use de-ionised or distilledwater as these will not leave anymineral deposit on the surface of the object.

Useful for:• General washing of objects and

removal of dirt from intricatesurfaces.

• Removing organic adhesives,especially when applied in a cottonwool poultice.

Glass and most glazed ceramics can be placed in a padded bowl andwashed with a cloth or small sponge.Glazed ceramics with gilding, over-painted areas or transfers should be cleaned with a swab, not bywashing.

Acetone This evaporates very quickly and so isuseful for objects that should not bewetted.

Useful for:• Removing oil or grease.• Cleaning break edges before repairs

are made.• Removing slightly greasy dirt.• Removing adhesive residues.

Methylated Spirits (meths)A slightly in-between solvent – it does not wet as much as water butevaporates more slowly than acetone –this means Methylated Spirits canpenetrate the dirt layer and this can be an effective method of removal.

Conservation labs generally useIndustrial Methylated Spirits, whichdoes not contain bitrex or the purpledye and is a purer form of MethylatedSpirits. You will need to apply for aspirit licence from HM Customs andExcise to be able to buy it. For thisreason, purple meths is sometimeused. It does the same job, althoughthe purple dye may stain absorbentsurfaces – test first.

Useful for:• Removing greasy dirt.• General dirt removal.

White Spirit This solvent does not affect as manysurface finishes as acetone and meths,but it does have a very pungent smell.It should not be assumed that this is a“safe” solvent; use caution and test asfor the other solvents.

Useful for:• Degreasing.• Removing dirt and dust.

Spit (active ingredient salivary amylase,an enzyme)Human spit is widely available and is avery cheap solvent.

Useful for:• Removing dirt and dust. This is a

useful solvent to try if nothing elseseems to be working.

Method of use:Wet methods are usually carried out byapplying the solvent to the object usinga swab. This can be a purchased cottonbud or a hand rolled swab. Hand rollingallows you to make exactly the sizeswab required and is cheaper thanbuying cotton buds.

• Swabs should be rolled across thesurface.

• Swabs should be disposed of as soonas they are dirty – do not put a usedswab back into the solvent.

• If detergent is used, the objectshould be rinsed by going over thearea with a swab of plain solvent toremove the detergent.

• Swabs, and any other material usedwith solvent, should be disposed ofin a container that allows the solvent

Collections Successful Basic Conservation 10

Conservation labsgenerally useIndustrial MethylatedSpirits, which does notcontain bitrex or thepurple dye and is apurer form ofMethylated Spirits.

to evaporate slowly. This can be aswab jar – made from a jam jar witha hole pierced into the lid – or anempty drink can. Push the swab intothe hole and pull out against an edgeof the hole. This pulls the swab off.Cotton buds must be thrown awaywhole. Once the solvent hasevaporated completely the swabsmay be placed in a bin.

Polishing – Metals

This can be very damaging to objects –all polishing removes a micron-thinlayer of the surface and over time thiscan lead to significant damage, such as wearing away inscriptions. Buffingwith a lint free cloth or a silver cloth is very effective at removing smallareas of tarnish or dullness. Gentlecleaning with a very soft toothbrushand/or a swab with soapy water (hotwater can be more effective) willusually remove medium tarnishdeposits. Do remember to dry thesurface thoroughly as moisture left on the surface may encouragecorrosion.

Preventing tarnishing/dulling is themost effective method. Avoid handling

polished metal without gloves – fingermarks are very damaging. Tarnishinhibitors are very effective atpreventing tarnishing, although thecase or storage container needs to be well sealed for the inhibitor to bemost effective. They need replacingperiodically; the time interval dependson the level of pollutants in theatmosphere and how well sealed thecase/container is. Silver can be storedin bags made from inhibiting fabric.These are very effective over manyyears. (See web links)

Apply polish as infrequently as possibleand only when the dry methods givenabove are not effective. Polishes shouldbe used extremely sparingly, withmore attention applied to the removalof the polish than the application. Theshininess can then be maintained bygently buffing the object with a silver(suitable for non-silver bright work andcopper, but keep one just for use onsilver) or copper cloth. This also has theadvantage that the tarnish deposits willbe quite minimal and thus will notrequire much effort to remove themwhen the time comes to use polishagain.

11 AIM Success Guides

Swab cleaning showing swab jar andcleaned strip. Cleaning using a swab(home-made cotton bud) – see thecleaned strip on the object. The jarallows for safe and easy disposal ofthe used swab.

Method of use:On steel, copper or brass use SolvolAutosol/Autoglym, Prelim or similarpaste polishes. Use a tiny amount on a lint free cloth or swab. Rub gently,allowing the paste to work – there isusually a moment when you will feelthe dirt begin to move. Buff off with alint free cloth or clean swab and makesure that all the polish is removed or awhite residue may be left that can bedifficult to remove. Work on a smallarea at a time and only use polishes onsmooth surfaces as rough areas tend tohold the polish.

Silver should be cleaned with silverpolishes in the same way. Alternatively,a polish can be made using calciumcarbonate, most easily available in theform of unscented talcum powder(although precipitated calciumcarbonate, from chemical suppliers is a smaller particle size and thus is lessabrasive), mixed into a paste withWhite Spirit, acetone or IMS. This canthen be applied on a swab and gentlyrubbed into the tarnish. Wait until it isdry and then brush it off with a smallbrush or use a small amount of solventto remove it. This is a relatively non-abrasive polish and is thus safer to usethan some commercial products. Theother advantage is that any residue canbe brushed off.

Polishing – Plastics and Wood

Plastics and wood can also be polished.This removes dirt and adds a shine tothe surface. Excessive polishing canlead to a build up of polish that may bedisfiguring, attract and hold dirt on thesurface and may damage the surface.Consequently all polishing should beundertaken with caution and asinfrequently as possible.

Buffing with a soft cloth should be thefirst method tried, but do not attemptthis if the surface is flaky or otherwiseunstable. If the wood seems very drythen polish is useful, but if the wood isnot handled, meaning that the polish isnot worn off, then regular polishingisn’t necessary and should be avoided.

Beeswax polish can be used, but this can become tacky at roomtemperature, meaning that dust sticks to the surface. Renaissance(microcrystalline) wax is a syntheticwax and is hard at room temperaturebut it can be difficult to remove. Applyvery sparingly with a soft cloth andthen buff. Don’t use spray siliconepolishes as these build up a layer ofsilicone which can be disfiguring and is difficult to remove.

Plastics can be polished to restorecolour using abrasive polishes, but as in metals, this does remove a thinlayer of the surface and this is oftennot appropriate for collection objects.Wax polishes can be applied to somematerials but is only suitable for a small range of plastics. If you do notknow what the plastic is, seek advicefrom a specialist. Guidance can befound in “Plastics. Collecting andConserving”.

Corrosion

Much corrosion is stable and actuallyforms a protective coating on thesurface, preserving the metal beneath.As a general rule, a dull colourcombined with a very adherent,coherent surface means that thecorrosion is inactive and stable. It isgenerally preferable to leave thiscoating well alone. This is a counterintuitive response and many peoplefind it uncomfortable. It is helpful toremind oneself of the basic approachthat our duty is to keep the objectstable for as long as possible and thatchanges to objects can often add to its valuable ‘story’. If removal isdeemed necessary, then very fine wire wool (0000 grade) can be used in combination with Autosol or similar polishes or a mineral oil such as 3 in 1. Only try this method on hardmetals such as steel, iron or brass;softer metals may be irreparablydamaged. Corrosion that has a bright,vibrant colour and is powdery (it may also be present in small spotsrather than covering a large area) is

Collections Successful Basic Conservation 12

Much corrosion isstable and actuallyforms a protectivecoating on the surface,preserving the metalbeneath. As a generalrule, a dull colourcombined with a veryadherent, coherentsurface means thatthe corrosion isinactive and stable.

usually active and action should betaken to prevent further corrosion. Thisoften means moving the object to anarea of lower relative humidity orremoving a source of acid, such asdeteriorating plastic. By treating thesource of the corrosion, it is muchmore likely that the object will surviveas corrosion is much less likely to re-occur.

6. Repair

Repair work needs to be very carefullyconsidered and always approachedwith caution. Before attempting arepair, it is important to consider whythe repair is deemed necessary – is itactually necessary to make a repair oris it possible to understand the objectby some other method, such as areconstruction image?

What Should You Use?

In the past, all manner of materialswere used to repair objects, oftenthose that would allow the object toextend its useful life. These methodswere often intrusive and disfiguringand many actually caused furtherdamage to the object, e.g. rivets usedto repair ceramics required holes to bedrilled into the object; corrosion of therivets can lead the ceramic to breakagain. The decay of these old repairsoften results in discoloured areas,which can be very disfiguring.

Materials used in conservation today tomake repairs should be:

• Removable, so that they can easilybe removed from the object withoutdamaging it.

• Non-yellowing, so that they do notbecome disfiguring as they age.

• Weaker than the object, so that if theobject undergoes stress, theadhesive should fail (break) beforethe object does so that the adhesivedoes not cause the object to becomedamaged further.

The adhesives used commonly inconservation are:

Lascaux. This is quite a wet, acrylicadhesive, water based and soluble inwater. It is useful for repairing woodand organic materials, although it canmake textiles very stiff and should beavoided for these materials. If this isunobtainable, you could try usingcommercial Wood Glue but try to findone that is water based rather thansolvent based as the solvents can causethe adhesive to discolour.

HMG This is an adhesive based oncellulose nitrate, solvent based andsoluble in acetone and IMS. It isavailable ready mixed in tubes fromconservation suppliers. It is useful forporous ceramics, wood, plaster andsome synthetics.

Paraloid B72 An acrylic co-polymeravailable as resin or ready mixed. Theresin is soluble in acetone and can bemixed in many different ratios ofsolvent to resin to give a thin adhesivethat can be painted onto cracks or athick adhesive that can be used to jointwo pieces together. It is useful forceramics, wood, plaster, small joints instone and some synthetics.

The bond created by HMG and Paraloidis not a strong one. It will hold objectstogether, but the bond may not beenough to support the object –additional support may be required.The bond will not be strong enough ifthe object is to be used, perhaps aspart of a handling collection, and soadvice should be sought from aconservator on alternatives.

Treat adhesives like solvents and testfirst to ensure that there is nodiscolouration etc.

These adhesives are suitable for most3D objects. It is strongly recommendedthat you do not make repairs usingadhesives on paper, textiles or oilpaintings without seeking advice froma conservator. These items may beirreparably damaged by inappropriateadhesives.

13 AIM Success Guides

In the past, all mannerof materials were usedto repair objects,often those thatwould allow theobject to extend itsuseful life.

General method for making a repair:

• Carefully test fit the broken pieces,ensuring that the edges are notground together – this could causefurther damage.

• Will the object require support whilstthe adhesive sets? If so, haveplastazote, tissue scrunchies or a trayfilled with sand ready. Covering thesand with cling film will prevent theobject from being scratched.

• Cut several small lengths of maskingtape and stick these to the edge ofthe bench close to where you areworking.

• Ensure that the joint edges areclean – clean and degrease with aswab of acetone.

• If the material to be repaired isporous or absorbent, paint a dilutedlayer of adhesive onto the surfacewith a small brush and let this dry.This helps to seal the break edges sothat the adhesive is able to make abond rather than be sucked into theobject.

• Paint a very small amount ofadhesive onto one surface and jointhe two pieces of the break together(making a joint).

• Test the edge of the joint with theend of your thumbnail. If you can feela slight ridge, the joint is not properlyaligned – carefully manipulate thepieces, testing with the thumbnailuntil there is no ridge. Note that itmay not be possible to get acompletely smooth joint if the objecthas sprung. The act of making anobject often creates tension withinthe object, especially in glass andceramics. When the object breaks,the tension is released and thisallows the pieces to expand slightlyor spring. Consequently, the piecesmay never fit back together perfectly.Aim for the best fit you can get.

• Pushing the two pieces together, takeone of the pieces of masking tape.Stick it to part of the object abovethe break quite firmly. Pull the tapetightly over the joint and press itdown on part of the object below thejoint. Repeat with other pieces of

tape until the joint is held securely.• Support the object until the adhesive

is set.• Once the adhesive has set, but is not

hard, carefully remove the tape andremove any adhesive that hasdribbled out of the joint. It isgenerally easiest to do this usingsolvent on swabs – acetone willremove most adhesive residues,although water may be better forPVA. Remember to clean both sidesof the object.

• Let the adhesive set completely anddocument what has been done onthe object record.

Old Repairs

It is tempting to remove old repairs andreplace them with something lessdisfiguring and more conservationfriendly. Taking apart an old repair canbe a difficult operation and one thatmay result in further damage to theobject. Ceramic repairs involving rivetsare especially difficult to remove. Oldrepairs may be disfiguring, but it isgenerally safer for the object to leavethe repair alone. If the object is neededfor display and the repair is particularlydistracting, consult a conservator.

Stitched Repairs

Small repairs, such as restitching apress-stud to a garment, can be carriedout using matching polyester threadand reusing the existing stitch holes orsewing between the threads of thefabric. Larger repairs should be carriedout by, or under the guidance of, aconservator.

Professional conservators are highlytrained people and it is always worthgetting their advice and paying for theirwork. But the considered application of the approaches outlined here,underpinned by a good understandingof your collection and its needs, shouldgive all museums the confidence toundertake basic conservation: savingyou money and making your collectionmore sustainable!

Collections Successful Basic Conservation 14

Small repairs, such asrestitching a press-stud to a garment, canbe carried out usingmatching polyesterthread and reusing theexisting stitch holes orsewing between thethreads of the fabric.

Further Reading and Suppliers

Barclay, R., Bergeron, A. and Dignard, C.2002 Mount-making for MuseumObjects Canada: CanadianConservation Institute

Horie, C.V. 1987 Materials forConservation London: Butterworths

Rogers, L. ed. 1997 Ours for Keeps: Aresource pack for raising awareness ofconservation and collections care.London: MGC.

Quye, A. and Williamson, C. 1999Plastics Collecting and ConservingEdinburgh: NMS Publishing

2011 The National Trust Manual ofHousekeeping London: National Trust

Other Reading

Museums & Galleries Commission‘Standards in the Care of’:Archaeological Collections, 1992Biological Collections, 1993Geological Collections, 1993Larger and Working Objects, 1994Musical Instruments, 1995Touring Exhibitions, 1995Photographic Collections, 1996

All available through the Collections Trust web sitewww.collectionstrust.org.uk

Find them under the Collections Linktab and then Useful Guidance.

Online Conservation Resources

Conservation Online (CoOL):http://palimpsest.stanford.edu/Good links, general and specialisedinformation. Designed for conservationprofessionals.

ReCollections:http://amol.org.au/recollectionsVery useful site with good qualitygeneral advice on collections care.

Preserving my Heritage:www.preservation.gc.caAs above, useful site for generalcollections care advice from one of theworld’s leading organisations in thisarea.

Institute of Conservation (ICON):www.icon.org.uk. The UK body forconservation.

Conservation Register:www.conservationregister.com.An online directory of conservatorspractising in the UK; all the practiceshave achieved ICON’s professionalstandard of Accredited Conservator-Restorer, ACR.

Information about tarnish inhibitingmaterials for storage can be found at:http://bmagblog.org/2013/10/21/how-to-protect-your-silver/

Conservation Suppliers

The following companies supplymaterials for conservation, includingacid free tissue, gloves, storage boxes,smoke sponges, dust bunnies andmuseum vacs.

Preservation Equipment LtdVinces Road, Diss, Norfolk IP22 4HQ01379 647 400www.preservationequipment.come-mail info@preservationequipment.com

Conservation by Design LtdTimecare Works, 5 Singer Way, WoburnRoad Industrial Estate, Kempston,Bedford MK42 7AW01234 853 555www.conservation-by-design.co.uke-mail info@conservation-by-design.co.uk

15 AIM Success Guides

Collections Successful Basic Conservation 16

Conservation Resources (UK) Ltd15 Blacklands Way, Abingdon, Oxon,OX14 1DY01235 553166www.conservation-resources.co.uke-mail sales@conservation-resources.co.ukSupply Paraloid, HMG and Lascaux.

There are many other companies, butthese three carry a good range ofgeneral materials.

Edward W Mason Brush Manufacturers14 Brownfields, Welwyn Garden City,Herts, AL7 1AN01707 331 911e-mail masonsbrushes@btconnect.com

Excellent quality brushes at a very goodprice and often cheaper thancomparable cosmetic brushes.

Nilfisk-Advance LimitedUnit 24 Hillside Business Park,Kempson Way, Bury St Edmunds, IP31 7EA01284 763 163www.nilfisk-advance.com

Nilfisk UZ964 vacuum and bags. Thisvacuum is worn like a bum bag and hasproved very easy to use in all museumcontexts.

Satay sticks are available fromsupermarkets and kitchen shops.

Cotton wool (all-cotton is the mostabsorbent) from chemists andsupermarkets.

Microfibre cloths are available fromLakeland, John Lewis and somesupermarkets and the conservationsuppliers.

Autoglym and Autosol are availablefrom car supply shops, e.g. Halfords,hardware shops and somesupermarkets.

Silverglit, silver cloths and coppercloths are available from hardwareshops and supermarkets. An internetsearch will bring up many suppliers.

Nitrile gloves are available fromPreservation Equipment but are oftencheaper from scientific/medicalsuppliers. Check your local YellowPages or try Scientific and Chemicalwww.scichem.com

Jars for solvents, as above.

White Spirit and Methylated Spiritfrom DIY stores.

Acetone from chemists.

White Spirit, Industrial MethylatedSpirit and Acetone from scientificsuppliers, see gloves.

Acid free tissue is also available (and isusually cheaper) from local packagingsuppliers and is also available from theconservation suppliers. Make sure youget unbuffered and unglazed tissue.

Plastazote is also cheaper from themanufacturer than from theconservation suppliers. Check for local manufacturers or try

Ramplas Ltd84 Birmingham Road, Dudley, West Midlands, DY1 4RJt: 01384 453160f: 0121 535 7108e: info@ramplas.comhttp://www.ramplas.com

Jane Thompson Webb studiedArchaeological Conservation atCardiff University and becamea freelance object conservator,moving into collection care in2001. In 2004 she established,and continues to deliver, theRAW collection care trainingprogramme to museums andheritage organisations acrossthe West Midlands region,including sessions on basicconservation. It is her favouritepart of the job.

17 AIM Success Guides

aim-museums.co.uk

AIM Association of Independent Museums3 Chestnut Grove, Ludlow, Shropshire SY8 1TJRegistered in England No. 1350939 | Charity No. 1082215

Copyright © 2014 Jane Thompson WebbAIM Editor – Diana Zeuner