FAQ

Solvents

1. When should turpentine be used rather than white spirit?

Both Artists’ turpentine and white spirit can be used for diluting oil colour and cleaning brushes.  White spirit does not affect the colour of any pigments. There are however several issues concerning these two solvents.

 i] Handling properties - Turpentine is more viscous than white spirit and is slower to evaporate.  White spirit gives more ‘watery’ mixes, making the colour slightly less controllable and does not stay ‘open’ as long as turps.

 ii] Stability -  a residue of gum in turpentine will prevent an oil film from drying, leaving it tacky indefinitely.  The gum will also cause yellowing. It is therefore imperative that Artists’ turpentine and not that sold as ‘Genuine Turpentine’ for home decorating is used as the gum has been removed from the former by repeated distillation. 

In addition, turpentine will oxidise if left exposed to daylight or air, also resulting in tackiness and yellowing in the painting.  Turps should therefore be stored in well filled and sealed bottles away from daylight.  White spirit has neither a gum residue nor will it deteriorate on storage. 

Iii] Price -  Turpentine is considerably more expensive than white spirit.  

iv] Toxicity; Turpentine is slightly more harmful than white spirit.

In addition to these two solvents, Sansodor from Winsor & Newton is increasingly popular as a low odour solvent, ideal for those who object to the smell of either turpentine or white spirit.  It is petroleum based like white spirit, has none of the disadvantages of turpentine yet keeps the paint ‘open’, if anything, for slightly longer than turpentine.  It is also the least toxic of the three solvents.

Read more about using Solvents.

2. How can the odour from solvents be kept to a minimum?

To reduce the odour of solvent in your house, I would recommend using Winsor & Newton Sansodor, which is low odour.  Many artists paint within their home and here is a list of tips which should help:

• Ensure plenty of fresh air, ventilation and circulation.
• Do not sleep in your studio without first removing painting materials elsewhere and in particular, be sure to dispose of unused solvents and dirty rags in fireproof and solvent-proof containers.
• Store all solvents, tightly capped when not in use.
• Avoid excessive skin contact with solvents.
• Do not pour our more solvent than is necessary for your current painting session, it will only evaporate into the room.
• Avoid prolonged inhalation of solvent vapours.
• Do not use solvent to wash colour from your hands. 

And finally, if you want to avoid using solvents, then you may like to try Artisan Water Mixable Oil Colour which uses water rather than turpentine. 

3. What are the effects of using Turpentine Substitute?

Turpentine Substitute should never be used with oil colour.  It is a cheap DIY solvent, which when used, runs the risk of discolouration and non-drying of the oil colour.  Its only acceptable use for artists is for cleaning brushes.  The number of tacky paint films resulting from old turps or cheap DIY solvents are second only to the number of problems with sinking.

4. What is the nearest equivalent to Turpenoid?

The nearest equivalent to turpenoid the Winsor & Newton range is Distilled Turpentine.  Read more about Distilled Turpentine.

5. What factors need to be considered when selecting a solvent?

Solvents can be assessed in three ways; performance, price and their hazardous nature.

i] Performance -  it is important that any solvent used for painting purposes evaporates totally, leaving no residue.  A residue is likely to discolour the paint and can leave an indefinitely tacky paint film.  Solvents for painting must be artists’ quality to avoid these problems.  Artists’ turpentine evaporates slowly and produces viscous mixtures.  White spirit evaporates more quickly and produces more ‘watery’ mixtures.  Sansodor [low odour solvent] evaporates slowly and produces viscous mixtures.  Although many artists may argue that turpentine makes a more controllable colour, a low quality turpentine will be inferior to white spirit.  Turpentine substitute is a very low quality solvent which is only suitable for cleaning brushes.

ii] Price -  English Distilled Turpentine and Sansodor are equally priced with white spirit in the region of ¼ of that price.

iii] Hazardous nature -  all solvents are potentially harmful by inhalation, ingestion or skin contact.  It is good practice to keep the level of exposed solvent as low as possible, ie. no large open containers, maintain good ventilation and avoid repeated skin contact.  Relative to each other, turpentine is more hazardous than white spirit, which in turn, is more hazardous than Sansodor.

6. How can I tell when my oil painting is fully dry?

Dip a lint-free rag in solvent such as Winsor & Newton Artists' White Spirit, and rub gently on the painting surface.  If colour shows, additional drying time is needed.  If not, your painting is ready to be varnished.

Mediums For Oils

1. "Oiling out" is recommended for dull areas of a completed oil painting, how is this done?

'Oiling out' is the application of an oil medium to a painting which has sunk (become dull), or lost its oil to the layer underneath. The most common causes for this are an over- absorbent, cheap ground or the use of too much solvent and insufficient or no medium. When the colour is dry, Artists’ Painting Medium should be sparingly rubbed into any sunken areas with a clean cloth.

Wipe off any residue and leave to dry for a day or two. If smaller, dull areas remain, repeat the process until the painting has regained an even sheen. Varnishes should not be used for the purpose of recovering the lustre of a dead painting. For a faster drying oiling out medium, use Thickened Linseed Oil diluted with 50% white spirit (mineral spirits).

2. Which medium is best to create an Impasto effect?

Oleopasto will build texture and retain brushmarks.  However, adding medium will inevitably dilute the pigment concentration.  Ten per cent could go unnoticed, fifty per cent will definitely add transparency.  Adding white is another cheaper alternative to colour but results in tints. Winton colours are excellent for impasto work, the 200ml tubes are economical, the colours have excellent intensity and the nuances of Artists’ oils show least in impasto.

3. Can different mediums be used on one canvas?

Using different mediums with different drying rates on the same canvas is acceptable if the paint areas are not overlapping.  Cracking occurs if slow drying layers are underneath fast drying layers. However the canvas will be under more stresses than one with the same sort of paint film the whole way across the canvas.

Liquin

1. How does the "fat over lean" rule apply to the use of Liquin?

Fat over lean is better understood if considered as ‘flexible over less flexible’. When painting in layers, the proportion of medium used in each layer should be increased. The higher proportion of medium makes subsequent layers more flexible and prevents the painting from cracking. This rule has traditionally been kept by adding more and more oil to the solvent used. However, as Liquin is now more commonly used, it is the Liquin content which is increased. There is no need to use oil as well. Following this may appear to be against the “slow drying over fast drying” rule.  However, the increase in flexibility obtained, will be sufficient to handle any movement upon drying of the marginally slower drying lower layers.

For further information read our Hints, Tips & Techniques for Oil.

2. What quantity of Liquin versus solvent should be added to the colour?

Adding Liquin will make colour/a layer fatter. Adding solvent will make colour/a layer leaner.  Therefore only the lower layers should contain solvent and the upper layers should contain increasing amounts of Liquin.  Because Liquin is a medium and not a solvent there is no upper limit to its ratio with oil colour, however it is recommended that at high proportions the layers are applied as finely as possible.

For further information read our Hints, Tips & Techniques for Oil.

3. How do I clean Liquin from my brushes?

Brushes should be rinsed in white spirit, at least every hour, throughout your painting session, to ensure the Liquin dissolves.  Work the solvent well into the end of the brush.  At the end of the day wash your brushes in warm water and soap, or a brush cleaner, until no further colour comes out. Liquin is an oil modified alkyd resin, whose principle property is its quick drying.  Unlike oil colour, which will not dry on the brush during a day’s painting session, Liquin will start to dry in 2 hours.  Once dry, it will not be removable without the use of a paint stripper which, is not always kind to brushes.

4. Which medium will improve the flow of oil colours without making the finished painting glossy?

Liquin makes a lower sheen than linseed oil and will improve flow.  Using some solvent with any medium will also ‘cut’ the gloss effect.

5. How much quicker will oil dry with Liquin?

Liquin will approximately half the drying time of oil colour, dependant on the proportions added.  So depending on the climate, colours used, and film weight the layer will be touch dry in any thing between 1 and 5 days.

For further information read our Hints, Tips & Techniques for Oil.

6. Can Liquin be used as a varnish or final coat?

It is definitely not advisable to use Liquin as final layer to a painting based on the reasons below:

• Unlike modern picture varnishes, when dry Liquin is not soluble in normal paint solvents. Therefore when the picture surface becomes discoloured by ingrained dirt from the atmosphere, it cannot be either completely cleaned or removed and the picture re-varnished.
• Although Liquin has much better resistance to yellowing than linseed oil, it will discolour more than acrylic varnishes.
• Liquin will seal the surface of the painting and prevent the drying of underlying paint layers. This is similar to Artists' Painting Medium. All produce a continuous film which excludes oxygen and delays the drying process - hence the recommendation to wait at least six months before varnishing. It is therefore advisable to use one of the Winsor & Newton specifically formulated varnishes. 

For further information read our Hints, Tips & Techniques for Oil.

7. What is the best equivalent to the discontinued Wingel?

The nearest product current Winsor & Newton range is Liquin Light Gel.   In some cases Win Gel was a little difficult to break down and to mix smoothly with colours.  For this reason it has been ensured that Liquin Light Gel has only a slight structure by comparison and that it is slow to set up.  Obviously it is difficult for us to meet the preferences of all of our artists, given the widely varying techniques and so we do not make these decisions lightly. If a little more structure in mixes is required add a little Liquin Impasto.  This should be done with care though as it is not as transparent as Win Gel or Liquin Light Gel.  

Drying Oils

1. How do the types of linseed oil differ?

Cold Pressed Linseed Oil will dry slightly quicker than Refined Linseed Oil and may have better flow with some colours.  Bleached Linseed Oil is paler than refined for mixing with whites and blues and dries quicker.  Stand Oil is paler and thicker than refined and is the slowest drying linseed oil.  Drying Linseed Oil is the fastest drying linseed oil.

Read more about Drying Oils.

2. How do Poppy and Safflower oil differ from traditional Linseed oil as mediums?

Poppy and safflower are classed as semi drying oils, whilst linseed is a drying oil.  Semi drying oils are paler than linseed but dry more slowly.  Safflower oil is not available as a medium.  Poppy oil is supplied as Drying Poppy Oil, which has added driers to it. This provides a pale medium for use with whites and blues but with a comparable drying rate to linseed to help avoid cracking.

Varnish

1. How can Dammar Varnish be safely removed from an oil painting?

Dammar varnish can be removed using any of our three oil colour solvents, Distilled Turpentine, Artists' White Spirit and Sansodor.  It is recommended to use Distilled Turpentine as this has the strongest solvency. 

Using a lint free cloth dipped in the turps rub the surface of the varnish. Dammar varnish can be slightly more difficult to remove than other varnishes.  The varnish should come off onto the cloth.  If any colour also removes onto the cloth then it is time to stop.  Work your way in patches across the entire surface of the painting.  It is best to keep taking fresh pieces of cloth to aid with lifting the varnish rather than spreading it.

2. Is it possible to paint over a layer of Artists' Retouching Varnish for Oil Colour after a month of drying?

It is possible to paint on top of Retouching Varnish.  It is best to keep subsequent layers of colour as "fat" as possible (thinned with lots of medium) and applied as finely as possible.

A layer of artists' varnish should then be applied after the last application has been allowed to dry for 6 months.

3. Why should an oil painting be varnished?

Varnish is desirable for two key reasons: one, to bring the surface to a uniform gloss level (matt or gloss or somewhere in between), and; two, for protection from dust and other atmospheric contaminants.

4. How should an oil painting be varnished?

Varnishes are used to protect the finished painting. Picture varnishes should be removable so that paintings can be cleaned when they have become dirty.

There are two important things to remember about varnishes:

1. Don't varnish too early, even the thinnest oil painting should be allowed to dry for 6 months. A minimum of one month is required for thin Griffin alkyd paintings.
2. Don't use varnishes as mediums, this would make the painting sensitive to solvent. An attempt to clean it in the future may remove the painting instead.

Here are some simple steps to varnishing success:

1. Use a 1”- 4” flat wide, soft, tightly packed, varnishing brush.  Keep it clean and use it only for varnishing.
2. Place the work to be varnished flat on a table - do not varnish vertically.
3. Apply the varnish in 1-3 thin coats, rather than 1 thick coat. A thick coat will take longer to dry, may dry cloudy, drip or sag during application and has a greater chance of showing brush strokes when dry.
4. Thinned varnish is more susceptible to producing bubbles. Do not be vigorous in your application.
5. Apply in long even strokes to cover the surface top to bottom while moving from one side to the other. While working, inspect the varnish layer at all angles for bubbles. Even them out immediately.
6. Once you leave an area, do not go back over areas that you have done. If you do, you risk dragging partially dry resin into wet, which will dry cloudy over dark colors. If any areas were missed, allow to dry completely and re-varnish.
7. After varnishing, it is recommended that the surface should be shielded from dust with a protective plastic film “tent”.

5.  How can I tell when my oil painting is fully dry?

Dip a lint-free rag in solvent such as Winsor & Newton Artists' White Spirit, and rub gently on the painting surface.  If colour shows, additional drying time is needed.  If not, your painting is ready to be varnished.

6.  How can an artists' varnish be removed from a painting?

If the painting is particularly valuable then it should be taken to a conservator. Otherwise, the best product to use would be our Distilled Turpentine. 

Dip a lint free cloth into the turps and gently rub the surface of the painting.  Start in a corner.  The varnish should come off onto the cloth.
If any colour can be seen on the cloth then you should stop.  Working in small squares, proceed across the entire surface of the painting.  It is best to keep using fresh pieces of cloth as this aids lifting the varnish rather than spreading it.

8.  How should an Artisan Painting be varnished?

Varnishes provide a transparent coating which protects your finished painting from general dirt. Picture varnishes are removable, enabling the painting to be cleaned in the future. Varnishes should not be used as mediums for adding to the colour. Artisan paintings should not be varnished until thoroughly dry (at least 6 months). There are three Artisan varnishes available – Gloss, Matt and Satin depending upon the desired finish.

The painting will benefit from being de-greased before varnishing. This can be done with either Artisan Thinner or Artists' White Spirit (mineral spirits). Simply wipe over the surface of the picture sparingly and leave to dry overnight.

Apply the varnish using a large dry varnishing brush, immerse the brush in the chosen varnish and apply in long steady strokes across the painting surface.

To ensure the desired result, test before use. Matt and Satin should be shaken or stirred well before use and should not be used on absorbent or damaged surfaces.

9.  How can Artisan varnish be removed?

Artisan Varnish can be readily removed when dirty. To remove Artisan Gloss, Matt or Satin Varnish, apply the Varnish Remover generously onto a lint free cloth and gently rub into the varnish film. If slight pigment is visible on the cloth this is an indication that the removal has been successful. Use plenty of clean cloth to ensure varnish is being removed from the surface. Avoid undue abrasion.

10. Why should an Acrylic painting be varnished?

As the acrylic film approaches its final dry state, the last few evaporating water molecules leave micro-pores in the film. These pores cause the film to feel tacky, even when fully dry. The micro-pores remain open indefinitely, meaning that the porous acrylic film can freely accumulate dust, grime, and smoke from the atmosphere.  While that grime may not seem to be much over a week or a month, it adds up over the course of years.  The best way to protect the painted acrylic film is to varnish. Winsor and Newton produce a range of acrylic varnishes.

11. How should Winsor & Newton acrylic varnishes be applied?

Thinly painted acrylic films may be vanished after 24 hours of drying time, but up to a week of drying time should be allowed for heavy or impasto layers before varnishing. In addition, varnishes may be intermixed for a variety of finishes.

Here are some simple steps to varnishing success:

1. Use a 1”- 4” flat wide, soft, tightly packed, varnishing brush (such as the Winsor & Newton Monarch glazing/varnishing brush).  Keep it clean and use it only for varnishing.
2. Place the work to be varnished flat on a table - do not varnish vertically.
3. Apply the varnish in 1-3 thin coats, rather than 1 thick coat. A thick coat will take longer to dry, may dry cloudy, drip or sag during application and has a greater chance of showing brush strokes when dry.
4. Thinned varnish is more susceptible to producing bubbles. Do not be vigorous in your application.
5. Apply in long even strokes to cover the surface top to bottom while moving from one side to the other. While working, inspect the varnish layer at all angles for bubbles. Even them out immediately.
6. Once you leave an area, do not go back over areas that you have done. If you do, you risk dragging partially dry resin into wet, which will dry cloudy over dark colors. If any areas were missed, allow to dry completely and re-varnish.
7. After varnishing, we recommend that the surface should be shielded from dust with a protective plastic film “tent”. 

12. How can Winsor & Newton acrylic varnishes be removed from a painting?

Acrylic Varnish can be readily removed when dirty. To remove Winsor & Newton acrylic varnishes, apply the Galeria Varnish Remover generously onto a lint free cloth and gently rub into the varnish film. If slight pigment is visible on the cloth this is an indication that the removal has been successful. Use plenty of clean cloth to ensure varnish is being removed from the surface. Avoid undue abrasion.

13. What is the best way of using Winsor & Newton aerosol varnishes?

Here are some recommendations on how to use Winsor & Newton aerosol varnishes and avoid clogging of the nozzle:

1. Try not to store aerosols below 15'C (59'F) - if they have been stored around this temperature - do not use them until they come up to ambient again - all aerosols contain a mix of product and propellant - at lower temperatures the products wants to "drop out of solution" and so could either block the nozzle, or worse, come out of the nozzle as "blobs of product" which then fall on the work itself.
2. Always shake the container vigorously before use to ensure the contents are homogenous.
3. Always hold the container upside and spray for a couple of seconds - this will send a spray of propellant only out of the nozzle and clear it
4. Always do this at the end of use as well to clear the nozzle of material build up.
5. Be careful if using the container extensively over a short period of time as the contents temperature will drop with a potential for the product to "drop out of solution" - this applies to all aerosols but is only likely to be noticed during extensive use.
6. Always spray with the can almost vertical and allow the contents to "cascade onto the work".
7. Mount the work onto "waste material" and spray side to side beyond the extremities of the work to ensure full coverage.

14. How quickly does Japan Goldsize dry?

Japan Gold Size is very fast drying and therefore will be dry within a few hours at average temperature and humidity.