George O'Hanlon
I find it interesting that anyone today who understands even a fraction about making oil paint would recommend cold-pressed linseed oil for making oil colors. I know it is recommended in some of the artist's manuals, but it seems to me these authors never really understood the reasons why or simply copied what others had told them.
Why do we suppose the Old Masters went through such great lengths to "clean" or process their oils before using it in paint? Simply because they wanted to rid their cold-pressed drying oil of foots and other impurities, which cause problems in the dried paint film, such as yellowing.
Refined oils made by industry today are excellent products, and they do not have the faults of cold-pressed products. For example, I have samples of every type of drying oil (linseed, tung, walnut, sunflower, hempseed, poppy, high linoleic safflower oil, etc.) available in North America (and some from Asia and Europe). I can tell you that there are refined linseed oils almost as pale as walnut oil and yet have the same acid, saponification, and iodine values of cold-pressed linseed oil. So, where is the advantage of using cold-pressed oils? I cannot see any.
Also, when working with refined linseed oils, I have the choice of selecting among a variety of them: vacuum-kettled heat-bodied oils; closed-kettle heat-bodied oils; conjugated oils; boiled oils; non-breaking varnish oils; etc. The consistency of these products from year to year is also phenomenal, which I cannot say for cold-pressed oil.
Of course, I can understand the romantic notion of hand washing cold-pressed oil, bleaching it in the sun and the general tender loving care some artists express for their oil, but when it comes to results, it is hard for me to see the benefits.
George O'Hanlon Technical Director Natural Pigments
Posted: Jan 17, 2007
Ian
Where do you get all those different refined oils? All I see on the website is the Gamblin refined, which specifies "low acidity."
Don't you find the alkali refined stuff handles very differently? (worse, for my purposes)
Also, I would love to know how to do those different heat-bodied processes and I don't know what conjugated or non-breaking means... would love to know! Thanks so much.
Posted: Mar 11, 2007
George O'Hanlon
I am curious as to why you think alkali-refined linseed oil handles worse than cold-pressed linseed oil when ground with pigments.
George O'Hanlon Technical Director Natural Pigments
Posted: Mar 12, 2007
Ian
The alkali refined oils I have used walnut and linseed feel greasy. slippery in an odd way, like the oil might have more cohesion than adhesion. It seems to take longer to dry, too, but this other quality bothers me the most. I often don't use spirits to thin paint if I want it long, but with the alkali-refined stuff, it seems to gather on itself. I am not sure I am describing this well. Does it sound familiar to you?
Posted: Mar 23, 2007
George O'Hanlon
The refined oils may contain less fatty acids, may have a lower saponification value, and generally be more viscous (thicker), and may lead you to believe that they "feel greasy, slippery." I am unsure what you mean by the words "adhesion" and "cohesion" in this context. This is undoubted because you have only been working with what is sold by artists' suppliers. However, coating manufacturers (and, for that matter, artists' materials manufacturers) have a much greater range of drying oil products available to them. I am still working on getting all the new oil products on the website, so that the average artists can experience this range, too. [Note: Natural Pigments now has a wide selection of linseed, walnut, and poppyseed oil products in the online store.]
George O'Hanlon Technical Director Natural Pigments
Posted: Mar 23, 2007
Alex Sunder
George has a great point here. I was using the cold-pressed raw oil one day, searching through the painting materials, I found my old refined linseed oil bottle, and something just struck me... why the raw oil should be better if is so much dark and brownish than the refined oil?
I did a simple test on a small canvas, using only both oils and both oils mixed with different whites. The RAW oil, mixed with the whites, was terribly more YELLOWER than the refined oil. Two months later, I can see through my simple test that the whites painted with the COLD-PRESSED RAW oil got slightly less yellow, STILL yellower than the REFINED oil.
Bleaching in the sun is a waste of time since the oil can turn yellow again when exposed to light for a long time.
So, WHY BOTHER "washing" the raw oil many, many, many times, or bleaching the thing to death, leaving traces of water and other substances, just to achieve a product close to the refined alkali oil? Doesn't make sense at all. I'd rather use my time actually PAINTING, and yet, using a less yellow oil, such as the refined alkali.
Like George's statement, I strongly believe that the procedure the old masters used to apply on the RAW oil was used cause they DIDNT have the refined oil as a regular product around them back in their time. As Doerner said, the old masters didn't paint BETTER cause their materials were actually BETTER than ours, but because they had more KNOWLEDGE about their materials and had a more precise sense of applying and using these materials of their time, better than most painters have nowadays.
Artists should be able to UNDERSTAND and TEST their contemporary materials, and stay tuned to their own time, yet, LEARN from our old masters, but do not assume that just because its a OLD recipe that would be better than the stuff we have today. Check some of the few "fugitive" colours of the old times, they are now corrected by modern, better pigments, and someone who assumes that get the "real", old stuff would be better, will pay the price of seeing their lucious colors fading away with time.
Doing your own material and your own research is a risky business. I would rather consult someone ON THE BUSINESS, like Natural Pigments, doing my own research and cross link the information.
I only use refined linseed oil now, and when i want more subtles blending, or "airy" glow effect, i use stand oil. Pretty basic, pretty simple, pretty secure.Posted : Sep 16, 2007
Kenneth Freed
Like so many others, I had heard of the supposed superiority of cold pressed linseed oil and it's purported use by paint makers, so I used it in many medium formulations. I used it when I wanted a thinner medium than could be obtained by the kettle cooked (stand oils). I also read at one time that the linoxyn levels were higher with cold pressed linseed oil than other oils. Not being a chemist but rather an alchemist, it sounded good. I for one had no real idea that I was getting so much in the way of foots and other impurities.
Since I have now started to make many of my own earth color paints from Natural Pigments I have been using the refined linseed oil also offered by them to make the paint with. I have been very delighted at the quality of paint that can be made. It has a body and viscosity that handles very richly. It does not feel like some of the manufactured paint that I have used. I like the paint to be a little drier particularly for the underpaintings and I realize that I can give it just a little kettle cooked oil if I want a richer and creamier feel in the overpaintings.
Posted : Sep 17, 2007
Saturn
Hallo Mr. O`Hanlon, Mr. Freed and others in this wonderful and informative forum! It is a great delight to read and take part in the Art discussion here. I find Natural Pigments to be the best place for the artists to learn, exchange ideas and buy high quality materials.Having read first all the posted oppinions on this topic here I would like to share some of the most annoying problems that I have come across during the years associated with the use of alkali-refined linseed oils for preparing home-made oil paint meant for immediate use. Together with this I would also like to express some of my observations and personal oppinions on the use of these oils for the said purpose. I prepare my own oil paints using pigments and linseed oils already sixteen years.
According to my own understanding and experience before deciding which is the best oil for paint production one should take first into consideration what kind of oil paint the talk is about. Is it about hand-made own oil paint that is prepared for immediate use (1to 2- 3 days) or it is about oil paint that is meant to be kept in tubes for considerable time period? Another thing to be taken into consideration is will the made paint contain aluminium stearate or other stabilizers or not. I find both of these questions to be of exceptional importance because they both determine the handling, the behaviour during storage and the quality of the paint.
For paint that is meant to be stored in tubes the alkali-refined oil seems to be the only suitable oil because it is of low acidity. If unrefined cold pressed oil is used for this purpose the oil acids will start reacting with the pigments and even with the metals of the tubes(if not isolated) and very soon the paint will show hardening in tubes and other undesirable qualities. For such paint meant to be stored years in tubes the use of a cold pressed unrefined oil would be unthinkable.
For immediate use (up to few days maximum). If the paint will contain aluminium stearate( for consistency improvement), the use of alkali- refined linseed oil is a good grinding oil again. Because combined with the effect of the aluminium stearate it`s famous bad handling qualities disappear(but another ones take place) What I mean by this is that the gelling effect of aluminium stearate kills almost all individual differences between cold pressed unrefined and the alkali-refined oils. That is, in oil paint containing aluminium stearates in the high quantities that most manufactured paints in tubes contain , the choise of the oil is of little importance if the paint is going to be used soon after and is not meant to be stored in tubes. If it is of importance what kind of oil to use (alkali-refined or unrefined oil) such importance would arise from other concerns, not handling.
But if the paint is prepared for immediate use and will not be stored in tubes and will not contain aluminium stearates, highly oxidized oils, or mediums/varnishes containing highly acidic resins that congeal the pure oil-pigment paint, then the alkali-refined oil is not the best oil to use because of the fallowing reasons which I have observed during it`s use and which have always created me difficulties in painting
1. When mixed/ground with pure pigments that contain no other additives the alkali-refined oils of low acidity( most oils sold in Art supply stores) separate even in a few hours from the pigments and the perfectly formed thick paste of pigment and oil turns into a thick liquid mass when disturbed. This annoying appearance occurs most noticeable with Titanium and Zink or combinations of them both in white paints. When unrefined cold pressed oils are used this separation takes much longer to occur giving the artist time to complete his work first and never reaches such extreme appearance..
2. After the opaque paint containing alkali-refined oil is put on the canvas it stays perfectly shaped for some hours then it liquefies considerably and causes much of the oil to accumulate on the surface of the paint which dries very slowly, shiny, has greater tendency to wrinkle and yellow . Note that none of this happens when I am using cold pressed unrefined linseed oil especially if the paint contains calcium carbonate. However this varies from pigment to pigment-synthetic black oxide pigment Pbk 11 for example stays in perfect suspension with alkali-refined linseed oil and none of the above mentioned bad effects occur with this paint. Titanium white is the worst of all. Lead white does not liquefy because it chemically bonds with the oil and after once combined the oil does not easily separate.
3. Exactly as consequence of the above-mentioned reasons the alkali-refined oil paint dries forming more skin than the paint prepared with cold pressed unrefined (or only mechanically refined oil) and consequently yellows more. For I know from experience that the main mean to avoid yellowing when using linseed oil is to prevent the oil from excessive migration to the surface of the paint - The alkali-refined oil migrates to the surface of the pure pigment-oil paint more than all other oils and for this reason the paint yellows more./The paint, not the oil/ This is a change that takes part in the paint film which has nothing to do with the yellowing of the oil used, but with it`s migration on the surface of the paint. To prevent this the baroque painters added spike oil to the white paint which caused it to sink in and thus the accumulation of oil on the surface and the subsiquent yellowing was prevented by some degree. And the old masters did not use the alkali-refined oils of today.Had they, their problem to solve would be twice bigger. Of course some of them simply choosed walnut oil.
4 Paints made with alkali-refined oils dry slowly.
5. My tests show that paints made with alkali- refined oils do not yellow less than paints made with cold pressed unrefined oil, neither the oil by itself yellows less than the good quality cold pressed unrefined oils.( I have many test examples) I find them all sufficiently yellowing.
6. By simple tests one can see that although `freed` from mucilage, water and other impurities the alkali- refined linseed oil still yields a lot of mucilage during artist`s cleaning which makes the claims about it`s `purified` nature quite questionable.
7. It is said that the natural smell of the linseed oil is removed during the alkali- refining process. Actually the freshly expressed linseed oils have almost no any smell. It develops only in time. While the smell of the `smell free` alkali-refined linseed oil is quite unpleasant for many people.
These are few of the problems that I have come across while preparing my own linseed oil paint and I am sure that many other practical painters have had them too.
If anyone here has an idea how can these problems associated with the use of alkali-refined oils be avoided without switching to cold pressed unrefined/or refined without chemicals oils, please help with advise. I will greatly appreciate it. I read here about high acidity alkali-refined oils that were meant for industrial use but I cannot comment because i am not familiar with them.
I apologize for the long post and for my imperfect English.
Posted : Jan 14, 2010
George O'Hanlon
Excellent post, Saturn, and I will review it and make comments as I have more time. Thank you.
BTW, there is no need to apologize for your English. If I were able to write in a language other than my native one as you have done here, I would be very proud. I speak Spanish fluently, but I am not sure I could write as well in it.
George O'Hanlon Technical Director Natural Pigments
Posted : Jan 14, 2010
Paul Rhoads
Three cheers for cold-pressed unrefined linseed oil!
Posted : Jan 15, 2010
Kenneth Freed
Originally posted by Saturn:
According to my own understanding and experience before deciding which is the best oil for paint production one should take first into consideration what kind of oil paint the talk is about. Is it about hand-made own oil paint that is prepared for immediate use (1to 2- 3 days) or it is about oil paint that is meant to be kept in tubes for considerable time period? Another thing to be taken into consideration is will the made paint contain aluminium stearate or other stabilizers or not. I find both of these questions to be of exceptional importance because they both determine the handling, the behaviour during storage and the quality of the paint.
Saturn, you certainly have my ear. I love the aspect of talking about such issues in context of the kind of paint that you are attempting to make and particularly the usage. I think all too frequently we generalize about what is superior and what is inferior but we neglect the context in which it is to be applied. Your experience is valued. I look forward to learning more about your experience in many areas.Kenneth Freed
Posted : Jan 15, 2010
Saturn
Thank you , Mr. Freed!
I would be very glad if my knowledge would be helpful for the readers in this wonderful forum.
I myself love to read here and learn from all of you !
Posted : Jan 15, 2010
Saturn
Originally posted by Admin:
Excellent post, Saturn, and I will review it and make comments as I have more time. Thank you.
BTW, there is no need to apologize for your English. If I were able to write in a language other than my native one as you have done here, I would be very proud. I speak Spanish fluently, but I am not sure I could write as well in it. Thank you !
I am looking forward to receiving your suggestions. At my present location the cold pressed unrefined linseed oil costs three times more expensive than the alkali-refined oil and in order to buy it I must go to the next town while the refined linseed oil is cheap and available in every lockal Art material store. Nonetheless I am forced to buy the cold pressed for the reasons that I listed above. I wish I could start loving the refined product again as in the time when I knew nothing about the handling of cold pressed unrefined oil. I am so used to paint with home-prepared oil colours (because of the handling) that I use paints in tubes only when I don`t have particular pigment.Theoretically I find that the highly transparent colours in tubes that I have are very reliable and since I use these transparent paints only in shadows and generally in the dark backgrounds they can be useful. The body of the transparent colours especially with the addition of good viscous medium makes them not bad for my purpose. But for the semi-opaque and opaque colours like whites, yellows, natural yellow ochres,sienas, red ochres, indian reds, bright reds, umbras, blues and blacks I do not like the consistency and the handling of the paints in tubes, so I always make them myself.
And when I have all the pigments necessary for my work I do not want even to hear about paints in tubes.
Posted : Jan 16, 2010
J.A. Borgesse
I use tube paints exclusively, including Rublev's tube colors. Isn't it true that the use of regular cold pressed or alkali refined oil is best used for making paint rather than for use as a general painting medium with tube colors? There seems to be much confusion among painters regarding this issue. In other words wouldn't oil painting mediums using various heat bodied, sun thickened oils etc., regardless of whether they are made with cold pressed or alkali refined oils the prefered choice (especially for tube paints)? I find that regular oils used for grinding paints make less than desirable oil painting mediums when used alone or with slovents.
Posted : May 15, 2010
George O'Hanlon
It depends on what you want to do. Most artists approach the use of painting mediums incorrectly. They usually apporach their use as a necessity in painting rather than something used to achieve a desired objective.
For this reason I prefer to call them 'amendments' rather than 'mediums'. Amendments denote a substance used to alter the properties of the paint, but the word 'medium' can apply both to the paint vehicle and a substance used with paint.
I do not find that 'mediums' are absolutely necessary for painting, especially in every passage throughout a painting.
Painters can use refined heat expeller-pressed or refined cold-pressed linseed oil* to make paste paint more fluid, and this is a good approach if you want paint that is fluid without leveling and flow out. However, if you want paint that levels and flows, than the correct choice is bodied oil.
*All commercial, cold-pressed oils are refined, albeit with mechanical filtration, which is why I make the distinction between hot expeller pressed and cold expeller pressed. Alkali-refined oils are typically hot-expeller pressed and further refined with an alkali and other steps that eliminate almost all impurities. These additional processing steps eliminate most free fatty acids, waxes and mucilage, which substances may be useful when grinding certain pigments, but not for use as an amendment to paste paint.
George O'Hanlon Technical Director Natural Pigments
Posted : May 15, 2010
J.A. Borgesse
Thank you George. As usual, your advice and knowlege are illuminating. My work could be defined as somewhere between surreal, fantastic realism, symbolism, and visionary art executed with traditional painting techniques. Therefore my use of amendments is largely for unusual effects. Some of these effects stretch amendments to their limits and it is all too easy to make disastrous technical errors in the process--which is why sound advice is required. Therefore, I feel it necessary to learn as much as I can regarding the oils I use, their technical aspects/capacities and their correct application. Interestingly, since using Rublev tube oil paints, I find myself enjoying painting nearly straight from the tube with only a drop or two of NP sun thickened oil (which I love emensly). This is my first experience with pure oil and pigment colors and your's are so beautiful and well made that it seems almost sacreligious to add amendments to them. They handle quite differently from conventional tube colors and among other things are much easier to control. I can see why you advocate the sparse use of amendments; as you say the are not absolutely necessary.
Posted : May 15, 2010
George O'Hanlon
Thank you for the kind words about our paint. It is not accident that they handle nicely, seeing that this is as close to what the old masters would have experienced in their paints and they seemed to do right by them.
George O'Hanlon Technical Director Natural Pigments
Posted : May 15, 2010
J.A. Borgesse
There is a faded sign on a very old factory in New York City that reads "Perfection is no accident". Of all the signs in that city, it is the one that sticks in my mind. Likewise, the quality of your tube paints cannot be accidental but shows deliberate thought, carefull preparation and selection, and painstaking attention to detail. Perhaps it is my imagination, but your tube colors seem much more responsive to the addition of mediums/amendments than do conventional tube colors. Could this be due to the fillers and additives of the conventional colors; that is they seem to fight the mediums and I wind up using nearly twice as much of an given oil or amendment than with the Rubleve tube colors.
]Posted : May 16, 2010
Gnomo
This is an interesting thread. It has been very informative as I too have read all this conflicting info. concerning the use of Cold Pressed Linseed Oil. Like everyone here, I have tried many oils and I can say that in my personal experience, it really does go back to what you are trying to achieve. So, I agree with Saturn in this respect. One small point, though is the language distinction between Cold Pressed and Refined. I used to think that this meant the raw linseed oil, but I agree with George, this is unpleasant, does tend to yellow whites, etc. I think there is a distinction, after filtering through all these old manuscripts, between these oils. I believe that in the MS's, when the term "Cold Press" is used, it meant not heat extracted, but I do not think that this had anything to do with refinement. I believe this meant that after the cold pressing, the oil MUST be refined, and these MS's assume this is standard to the reader. The refinement here is the water washing, and removal of some of the dark yellow through various solid filtering additives as mentioned by others here. What is left is refined, but NOT with heat. It is my opinion that this oil is what is meant when "Cold Pressed Oil" is mentioned. This is a light flowery oil that is very nice to mull most pigments in. Part of this oil would be placed in the sun if you lived in the south, and in the north, they generally kettle cooked it with or without driers, or let it "stand" in the weak northern sun without air to polymerize for quite a few years. I have tried mulling pigments with sun thickened oil, and I have to say, I found this paint to be disagreeable and "ropey". But, for some reason, kettle cooked oils tend to make excellent paint, particularly with difficult pigments like blacks and ochers, which in my experience, are either runny, or seize up if just the aforementioned Cold Pressed(refined) oil is used. As far as Alkali refined, I have not had good luck with this for my applications. I don't know why, but I haven't been satisfied with the results. I have noticed like Saturn that Alkali tends to migrate after awhile. I do temper my paint with my preferred "amendment" of sun thickened oil no matter what it is mulled in, though, and this has generally served well in even sheen and drying times, but this is personal taste.
There is also another point I would like to bring up along the lines of what one is trying to visually achieve. For example, in the 1600's, there were several "colors" that were employed that were 2- 3 coat optical effects like deep crimson velvet (madder glazes), certain green foliage (verdigris) that required "amendments" to achieve this. These glazing colors were tempered with a single drop of resin to help give them a bit of body and handle better over an already dried 1-2 coat setup of underpainted layers. However, it appears that these were isolated areas of a painting(like cut-out shapes or giornata), and sometimes there are a few different ones within one work. Modern science has revealed this. These artists knew how to use just what they needed for a certain effect. I think modern painters are trying to find a "medium" that is like a panacea. We generally use this in all aspects of our paintings indiscriminately, which does give us less controlled results. I think we as modern painters are "searching" more, rather than executing, which is in my opinion the real missing "medium".
Posted : May 27, 2010
Paul Rhoads
Gnomo, I think this is a good point. Quite apart from artistic intentions, each pigment has its own characteristics, and, untimately, needs to be dealt with on its own terms. I use a pretty limited palette consisting mostly of earth colors, which share certain charateristics, but even there each is different, and needs to be attended to invidivually.
A profound problem with comercial tube colors is the strange lust of the manufactures to make a consistant product: different colors, one goo.
I particularly appreciate NP pigments because some are not fine-ground. I'm not sure about the reason for this (it's a choice you make, right George?. For example, the Sartorius red and the Glauconite (2 colors I use a lot) are pretty grainy, and I love that - both in itself, and the contrast with the finer ground pigments.
Posted : May 27, 2010
George O'Hanlon
Cold-pressing is a distinction about the method used to press the vegetable oil from the seed cake, and does not mean that it is raw. The seed cake is pressed at normal temperature, whereas the cake may be heated to increase the yield of oil with hot expeller pressing.
All commercially-available vegetable oils are refined in some way. The minimal refinement is usually done with fuller's earth or diatomaceous earth through a filter press, but industrial oils may also be treated with acids or alkalies, chilled and slightly heated to remove impurities.George O'Hanlon Technical Director Natural Pigments
Posted : May 27, 2010
George O'Hanlon
Originally posted by Paul Rhoads:
I particularly appreciate NP pigments because some are not fine-ground. I'm not sure about the reason for this (it's a choice you make, right George?. For example, the Sartorius red and the Glauconite (2 colors I use a lot) are pretty grainy, and I love that - both in itself, and the contrast with the finer ground pigments.
We grind pigments to their finest possible size using stone edge runner or ceramic ball mills. It is possible to grind them further using specialized mills in a process known as 'micronizing'. The former mills result in pigments with heterogeneous particle sizes and shapes, which we prefer to 'micronized' pigments, which are readily available from other suppliers. We have demonstrated that the heterogeneous particle size and shape of pigments result in different paint rheology, something that the old masters experienced with their pigments.
George O'Hanlon Technical Director Natural Pigments
Posted : May 27, 2010
Paul Rhoads
Well, I can only say that, having worked with pigments from the small group of secretive suppliers since the 1970s, NP is the best thing that has happened to the art materials market in my lifetime.
Posted : May 27, 2010
Darren Rousar
Originally posted by Admin:
We have demonstrated that the heterogeneous particle size and shape of pigments result in different paint rheology, something that the old masters experienced with their pigments.
If the painters of today experienced this aspect to its fullest, many of the paint mass producers would likely go out of business. Of course very few painters have the training to appreciate non-goo.
To be more polite, at least the world is big enough for George to succeed at doing what he does. It would be a great shame to lose this resource.
Posted : May 27, 2010
Gnomo
Indeed.
Being recommended to NP has been a nice surprise. I wish the co. all the best. The paint ground by a stone to the finest it naturally goes produces a paint that definitely dances off the brush. The transparencies glow and stay put.
The process of grinding the pigment under less pressure makes all the difference. It's like running with ankle weights on, and then having them suddenly taken off.
Pigments that are too finely ground tend to seize up from my experience, as I suppose they make something very sturdy, not something liquid like something that flows and tumbles.
One question I have is:
Because the oil paint is mulled without stabilizers, does it need a bit more time than paint with a stabilizer after it dries to the touch, to shrink and relax(move back and forth), or can the layers be layered the same way time-wise as paint made with a stabilizer?
( assuming we are painting with thinner layers, not impasto)
Posted : May 27, 2010
George O'Hanlon
Originally posted by gnomo:
Because the oil paint is mulled without stabilizers, does it need a bit more time than paint with a stabilizer after it dries to the touch, to shrink and relax (move back and forth), or can the layers be layered the same way time-wise as paint made with a stabilizer? (assuming we are painting with thinner layers, not impasto)
If I understood your question correctly, the answer is no; hand ground paint without stabilizers does not require more time to harden sufficiently for overpainting. In fact, paint additives, such as stearates, increase the oil absorption rate of pigments, so that more oil is required to make the same viscosity of paste, hence increasing the drying time.
George O'Hanlon Technical Director Natural Pigments
Posted : May 28, 2010
John Kennedy
As for my few bits of knowledge on cold press unrefined linseed oil in painting, I use a linseed oil from Sweden which is harvested high up in the mountains and only in the late fall. This has something to do with the actual purity of the raw linseed, from my reading about the product and its history.
Once I recieve this product the first thing I do is to filter it through muslin cloth three times and then return it to a cleaned bottle. I do this to take out as many inpurities as possible, but it is still in its raw state.
Next, I mix my pigments with this oil with a palette knife and then mull the pigment slowly adding the oil until I get the consistancy I am looking for and then I let it set for about 4 to 6 hours. Depending on the pigment used the standing pigment may bleed some oils out. If this happens I remull the pigment again but for a longer period of time and sometimes add a little sprinkle of the pigment to help pick up on the additional oil. This usually works and there is no more bleeding of the oil out of the pigment.
Whites, I have mulled for as long as an hour for the proper binding of the oil to take place with the pigment. Most colors I mull for 15 to 20 minutes. These are all ready for immediate use and if any is left that I want to keep I put in 1 oz. jars and they are useally good for a week or so if you pour a little oil over them.
To reuse from the jar, pour off the excess oil, remull and if to oily sprinkle a bit of the color while mulling and then start painting once it is the consistency you are looking for.
Mind you this is not for any kind of long term storage. Also, you can add what ever you want while painting, depending on what ever effect you are trying to create, to the paint while on your palette.
If you want a more matt look to the paint add a bit of beeswax to remove some of the gloss. It is best to run a sample test with the beeswax so you can see the results prior to adding to your painting. Write down your mixes and quantities for future runs, this take out the guess work.
http://members.soundclick.com/John+Kennedy
http://jrkcompendium.embarqspace.com
Posted : Aug 4, 2010
B Arnold
Hello, Firstly, I take your point about the redundancy of cleaning poorer-quality C-P oils when more suitable ones are now readily available to us. This is very encouraging... But please indulge me briefly! I ask as I am in possession of a relatively large quantity of cold-pressed linseed oil, and having studied in Florence with Daniel Graves (undoubtedly a Romantic of the type you describe) who is an advocate of washing/cleaning our oils (though I should point out he wasn't necessarily recommending C-P linseed oil) I had intended to follow his advice & try cleaning the C-P linseed oil I have, to see how it's properties change. I have read in Tad Spurgeon's book, The Living Craft, that Salt, Sand & Water refining is in his opinion a fine way to do this. Now on your advice I won't be buying any more cold-pressed linseed oil, but my (long-winded) question is this: can this SRO process produce a good painting oil, or will this be a waste of time? Many thanks.
Posted : Sep 17, 2015
Posted By : George O'Hanlon
When you absolutely know how refined and cold-pressed oils are processed then you understand that the washing process is a waste of time. However, having said that when you carefully consider what individuals like Tad Spurgeon and others are producing who advise wasing and exposing oils to sunlight, then you also understand that this process results in oil with different properties, because they are partially oxidizing the oils by exposing to both air and light. You can accomplsih similar things by exposing refined oils to sunlight, too.
George O'Hanlon Technical Director Natural Pigments
Posted : Sep 17, 2015
B Arnold
Message received, George! Thank you for your prompt reply, and sound advice. I shall try to sell my cold-pressed oil and buy better stuff instead!
