Editor’s Note:
Added April 26, 2022
For some time, our recommendation for artists using oils over acrylic has been to work over harder, matte acrylic surfaces and avoid working on softer gels and gloss products. Our intention was to optimize the level of adhesion that would be achieved on a toothier surface as well as avoid the potential for future cracking as the oil paints become more brittle. While we have not seen adhesion problems of oils on any type of acrylic, recent testing has shown the potential for cracking in certain instances and conditions when applying artist oils over all of the many brands of glossy acrylics we have tested. While we have not received notice from artists of this phenomenon, we are able to repeat this specific type of cracking in our Lab.
Please visit https://justpaint.org/revising-our-recommendations-for-using-oils-over-acrylics/ for an overview of our testing, results and updated recommendations for applying oil colors over acrylics.
For oil painters who find themselves eager to paint but reluctant to spend too much time or money on surface preparation, you might try working on paper. Paper can be reasonably priced, easy to prepare and less formal than panel or stretched canvas. If prepared properly and maintained with longevity in mind, paper can be a permanent substrate for sketches, studies and finished oil paintings.
Paper, like other natural fiber substrates such as linen or canvas, needs to be sized or primed before oil painting. Sizing protects the fibers from oil absorption, which can cause premature darkening, embrittlement and eventual degradation of natural fibers. The challenge of sizing paper is keeping it from warping. We have recently tested various ways to size paper, looking for products that both protect from oil absorption and cause the least warping. For this test, we used untaped and unstretched Arches® 140-pound, hard sized watercolor paper and Arches® Oil Paper. Oil Paper is specially formulated for use with oil-based media and requires no preparation before use. Since it is already sized, additional layers of acrylic product, Acrylic Gesso or Oil Ground can be used to reduce tooth or brush drag, but are not required to protect against oil absorption. The acrylic products we tested on Oil Paper caused very minimal to no warping and we saw no signs of oil absorption. Of the product we tested on the 140-pound watercolor paper, Fluid Matte Medium, Acrylic Gesso, Airbrush Transparent Extender and Matte Medium caused the least amount of warping. These products resisted oil penetration with two or three coats.
Image 1: Best results with no oil penetration and minimal warping – Fluid Matte Medium and Acrylic Gesso on Oil Paper.
Image 2: Good results with several coats – Fluid Matte Medium, Acrylic Gesso, Matte Medium and Airbrush Transparent Extender on 140-pound watercolor paper.
Images 3 & 4: Oil Absorption Test on unsized 140# watercolor paper: front side (Left) shows 3 drops of Alkali refined linseed oil, brushed oil, King’s Blue neat and King’s Blue thinned with oil, back side (Right) shows oil penetration. Similar tests performed on Oil Paper, Oil Paper with acrylic product and 140# watercolor paper with two or more coats of acrylic product showed no oil penetration.
We recommend smoothing the paper as much as possible between coats so as to not reinforce the curling with additional layers of acrylic. We found that gently running the paper over a table edge to oppose the warping or pressing the paper left it relatively flat. The final layer of priming should ideally be matte for increased tooth and porosity. We recommend allowing at least three days for acrylic products to fully dry before painting on them with oils.
Image 5: Running paper over the table’s edge to oppose warping
There are pros and cons about working on paper. Some positives are that paper can be shipped flat or gently rolled around a tube and can be stored in a flat portfolio. For exhibition, works on paper can be adhered to panel or matted and framed under glass. The negative for paper is that it is fragile and will expand and contract in response to changes in humidity. As oil paint becomes older and more rigid, this movement, as well as any flexing of the paper, can cause cracking. Paper can also tear and retain the memory of folds or creases. Heavy applications of oils are not recommended for paper without proper reinforcement.
All substrates have their strengths and weaknesses and paper is no exception. In the end, paper is a good choice for those who are looking for an economical substrate that is relatively easy to prepare. Paper is great for landscape painting or studies done outside the studio.
For another look at a previously published Just Paint article about Preparing Canvas for Oil Painting, visit: https://justpaint.org/preparing-a-canvas-for-oil-painting/
I have some oil paintings I have done on shellaced mat board. Do you suggest I frame them under glass or can I varnish them and not use glass.
Hi Laura,
You certainly have options based on your preferred aesthetic. It is good to know that shellac is brittle and becomes more brittle and darkens with time. We tested BIN® pigmented shellac on 140 pound watercolor paper for this article and found the results to be much more brittle than the paper sized with acrylic product or PVA. The paper sized with BIN readily cracked when bent. Framing with a backing board could support the matboard and help protect it from damage caused by bending. Framing under glass could help keep dust from the surface and offer some UV protection depending on the glass, but can be heavy and expensive depending on the size of the painting. Varnishing can offer UV protection and unify the sheen of the painting, but won’t protect the matboard from embrittlement. Adhering the Bristol to a rigid support could help mitigate issues associated with embrittlement.
You can find more information on GOLDEN MSA Varnish or spray Archival Varnish in our Varnishing Resource: http://www.goldenpaints.com/technicalinfo/technicalinfo_varnishresources
For more assistance, contact the Materials Application Department at help@goldenpaints.com or by calling 800-959-6543
Best Regards,
Greg Watson
I work with acrylics on paper. I gesso the paper and when dry it curls, so I then put the paper in a dry mount press and when I remove it, it is flat. An an alternate strategy, I simply mount the paper to 4 ply rag board.
Hi Bruce,
Thank you for sharing your successes with using the dry mount press to flatten your paper. We have not done testing with dry mount pressing. Our only reservations might be that gloss or thicker acrylic applications could flatten or distort under the pressure of the press.
Best regards,
Greg Watson
I regularly use 4-ply Strathmore Bristol Plate, primed with Bullseye shellac. There is no warping. What do you think about longevity of this approach?
Hello Joseph,
4 ply Bristol Plate made with 100% cotton fiber should be fine, but shellac is brittle and becomes more brittle and darkens with time. We tested BIN® pigmented shellac on 140 pound watercolor paper for this article and found the results to be much more brittle than the paper sized with acrylic product or PVA. The paper sized with BIN readily cracked when bent. You may consider testing the 4 ply Bristol for embrittlement by coating it with the shellac and then bending it to see if it is more brittle than uncoated Bristol or Bristol coated with Acrylic Gesso. Adhering the Bristol to a rigid support could help mitigate issues associated with embrittlement.
Best Regards,
Greg Watson
I have used 100# Bristol coated on both sides with several coats of commercial (Bullseye) shellac for use with oil paints. I did not see any evidence of the shellac cracking but only had them sitting for a few months at most. I mounted most of the finished pieces on UltraBoard using Goldens Matt Medium. I have only done this with small 6×6″ panels. I do paint with painting knives and use some heavy texturing. The finished paintings appear to be holding up well after several years.
( I left a comment on this same procedure in your section on painting on Bristol, before I saw this section).
Thanks so much for providing this venue!
Hello Pat,
Thank you for your comment – sorry for the delayed response! Bristol paper made with 100% cotton fiber should be a fine paper substrate for oil painting – the thicker the paper the better. In general, shellac is a brittle material and becomes more brittle and darkens with time. We tested BIN® pigmented shellac on 140 pound watercolor paper for this article and found the results to be much more brittle than the paper sized with acrylic product or PVA. The paper sized with BIN readily cracked when bent. You can test the Bristol you use for embrittlement by coating it with the shellac and then bending it to see if it is more brittle than uncoated Bristol or Bristol coated with Acrylic Gesso. Typically it takes quite an aggressive bend to see the results of this kind of testing, but it can provide insights to the nature of different sizing materials and how they might age over time. Keeping your oil paintings on paper flat in a portfolio or adhering them to a rigid support should help mitigate issues associated with embrittlement.
Best wishes,
Greg Watson
Did u also test adhesion of acrylics to arches huile paper? When i apply yr hi flow acrylics it heads up which apparently is bad for long term
Hello Bob,
We have tested High Flow on Arches Oil Paper and haven’t seen any excessive beading or adhesion issues. After the paint dried on those tests, we peeled the paint from the surface and it removed the top layers of paper with it, so we have reason to believe there should be good adhesion between High Flow Acrylics and Oil Paper. We have also contacted Arches and asked if acrylics can be used on the Oil Paper, which they said should be fine. If you have other concerns or questions about adhesion of GOLDEN High Flow Acrylics, feel free to contact us at help@goldenpaints.com or at 800-959-6543.
Best Regards,
Greg
It’s like you were reading my mind the past few weeks! Thanks for the great article, Greg, can’t wait to try this out soon!
Hello Caitlin,
Thank you for your comment! If you have any questions or concerns as you move forward, do not hesitate to contact the Materials Application Department at help@goldenpaints.com or by calling 800-959-6543
Best Regards,
Greg
Thanks for another very useful article! I’m wondering, if, say, one is planning to ultimately glue the paper to a rigid board (should the painting prove successful) if it would make sense to use GAC 200, rather than the mediums mentioned here, in order to stiffen the paper? Of course I’d have to do tests to ensure sufficient number of coats to block oil penetration etc but just wondering what your opinion is?
Hello Jenny,
We are not sure stiffening the paper would offer any benefit especially if you plan to adhere the paper to a rigid support. In general, we do not recommend using GAC 200 on a flexible support such as paper. Two coats of Fluid Matte Medium or Acrylic Gesso should be fine. They are more flexible than GAC 200 but should match the flexibility of the young oil film painted on top.
Here is a link to a video showing adhering watercolor paper to a panel: https://www.youtube.com/watch?v=ggB1veQmwNU
If you have other questions or concerns, please contact the Materials Application Department at help@goldenpaints.com or by calling 800-959-6543
Best Regards,
Greg
I don’t see why you are reluctant to stretch the paper in the normal way by wetting and taping, you will have to use a drawing board to work on the paper, so you may as well have it securely taped down in the first place.
Hello Laurence,
Thank you for mentioning that. Our intention for this test was to see how the different acrylic products would affect unstretched watercolor paper. That said, your point is a good one. Wetting the paper so that it swells, then taping with a wet adhesive tape or even stapling it to a rigid support while it is still wet can produce a drum tight, flat surface once the paper dries and shrinks back down. We would still recommend several coats of acrylic product to protect the paper from oil penetration. This can be applied to the stretched paper which subsequently will puff up and look distorted, but which should return to a nice, flat surface once the acrylic dries. This stretched and sized / primed paper can then be painted on with oil paints or removed and trimmed for later use. Happy Painting!
Best Regards,
Greg Watson
Great article here Greg.
I was surprised to see you didn’t tape the paper down before priming which is the way I’ve usually seen this practiced, but it makes sense not to if you are going to coat both sides and even out the stress. Can you comment on this?
Cheers, Grant
Hello Grant,
It is great to hear from you. Thank you for your comment! We found that taping the paper down before priming didn’t necessarily stop the paper from buckling. We also wanted to prime all the way to the edge of the paper to get an even tension across the entire surface instead of having a boarder of unprimed paper. For this test, we did not prime the back of the paper. We chose this method simply to see which products caused the least buckling of the surface. We wanted to recommend something that blocked oil penetration, was easy to prepare and cost effective. Priming the back of the paper requires twice as much product and can take twice as much time. That said, we have found that applying acrylic product to the back of the primed watercolor paper can help to even tension and flatten out the paper. The very best case scenario we found, which we did not mention in the article because it was much more involved, was stretching the paper. We did this by soaking the 140# watercolor paper in a bath for up to an hour and then stretched it onto a homasote board when wet. We attached the paper to the board with staples. When the paper dried, it was tight as a drum. It swelled when acrylic product was applied on top, but went back to being very tight when dry. Stretched and primed paper should not swell when oils are applied on top. We hope this is helpful!
Best Wishes,
Greg Watson
Ok very interesting, thanks for the feedback and clarification here Greg.
CIao, G
Just came across this article! Thank you!
I have been painting in oils on Heavy 640 Arches. Some pieces I’ve used a double or triple layer of Luquitex gesso prior to painting in oils.
With the heavy paper I don’t have much of a problem with warping. If there is some I spray water on the back and sandwich flat with weights.
If I need to balance the sheen of the oil I use a Gamvar mix as a finisher. It is then mounted under glass
I’m hoping this process is archival!
Hello JO,
Thank you for your comment! Three layers of Gesso should be sufficient to block oil penetration. We recommend six months to a year before varnish. Other than that, your process sounds fine. Mounting under glass should help protect from dust and dirt.
We wish you well in your studio. Please let us know if you have any other questions or comments. We can be reached by phone at 800-959-6543 or email at help@goldenpaints.com.
Best Regards,
Greg Watson
Hi Greg
Great article thank you! I’m curious about what type of varnish you would recommend? I experimented using regular 300g/m cold press watercolor paper primed with a couple coats of acrylic before I used my oils. Surprisingly no buckling or seepage at all.
Thankyou!
Hello Glynis,
That sounds great! You can use GOLDEN MSA Varnish with UVLS for oil paintings. It does a beautiful job unifying the sheen and providing UV protection. We recommend allowing the painting to cure for 6 months – a year before varnishing. That way, the varnish will be less likely to intermingle with the paint layers and sink in, which can cause variation in the sheen and make varnish removal more challenging in the future.
Here is some info on MSA Varnish: https://www.goldenpaints.com/technicalinfo/technicalinfo_msavar
Feel free to call or email with any other questions at 800-959-6543 or help@goldenpaints.com
Best,
Greg
Interesting article. I’ve done a couple oil paintings on Arches Watercolor paper (unprimed). I work with extremely thin layers of oil paint, so I haven’t had any trouble with the paint penetrating through to the back of the paper. I just use a spray varnish (Grumbacher professional quality non-yellowing oil paint varnish) on it once it’s sufficiently dry. As long as I’m not working with really heavy layers of paint, I’m guessing that priming the paper isn’t really that crucial – correct?
Hello Christine,
Thank you for your comment. When painting on an absorbent surface like watercolor paper, it is likely that some oil is being drawn out of your paint layer into the substrate, no matter how thin the layers are. This small amount of oil may not be significant enough to stain the back side of the paper, but may be enough to degrade the paper at the interface where the oil paint is adhering to the surface. Over the long term, this could weaken that interface and result in the paint layer being poorly bound to the paper. Moving forward, we would recommend a sized paper. If you enjoy the visual effect and feel of painting directly onto the raw paper, then an alternative could be a pre-sized paper intended for oil painting, such as Arches Oil. If, on the other hand, you are interested in sizing the watercolor paper yourself, we recommend 2 coats of clear acrylic medium, like Fluid Matte Medium or GAC 100 or 3 coats of Acrylic Gesso to block oil penetration. For the pieces you have already made without sizing, framing or mounting so to keep the paper flat would be preferable. Feel free to call or email if you would like to discuss these options.
We hope this information is helpful! Best wishes in the studio.
Greg Watson
Materials Application Specialist
help@goldenpaints.com
607-847-6154 / 800-959-6543
Since gesso is chemically similar to acrylic paint would it possible/acceptable to prime paper with a few layers of acrylic house paint?
Hello Maureen,
It depends on your expectations for the longevity of the paintings. While house paints are similar to artist’s acrylics, they tend to use different binders and are not made for maximum flexibility, UV stability and minimal yellowing like professional acrylic artist paints. It should be fine to make studies or sketches using house paint on paper, but if you are making paintings that you hope to last, it is probably best to use a quality acrylic gesso or acrylic medium. Of the house paint options available, higher quality, exterior paints tend to use better acrylic binders and are more UV stable than interior paints. In most cases, cost is directly related to quality. It should be possible for you to test flexibility by applying some house paint onto the paper, letting it thoroughly dry and then bending the paper to see if is stiff and/or breaks.
We hope this helps!
Greg
Hi Greg,
I’ve been working with oil paints on heavy paper, sized with rabbit skin glue (old school). I really like working without acrylic size..
My sense is that there are two options for “finishing” works of oil on paper:
1. frame as is, under glass (no varnish)
2. mount to board and then varnish (??) However, please help me figure out what is the best varnish for oil on paper… What do you recommend?
Hello Kate,
GOLDEN MSA Varnish with UVLS is the product we make that is compatible with oils. It is a solvent-based acrylic varnish with UV protection. It needs to be thinned before use with MSA Solvent, which is full strength mineral spirits, 3 parts varnish to 1 part solvent for a good brushable consistency. MSA Varnish also comes in an aerosol spray called Archival Varnish, ready to spray apply after vigorous shaking. We recommend waiting 6 months before varnish. Other brands also make varnishes forh oils. Check the label for varnishes that are compatible with oils, removable and do not yellow or harden with time.
Hope this helps.
Greg
Thanks for this article, really helpful guys! 🙂 I’m using acrylic matte medium over hanemhule watercolor paper, works wonders.
Hi Sebastian,
You are welcome. That is good to hear the Matte Medium is working well for you!
Thanks for sharing your experience.
Greg
Hello Greg,
I had a question about the reverse process.
Sometimes in the studio, I get going and find myself painting oils on papers that haven’t been pre-gessoed and then at the end of the day, it turns out I like the piece enough to keep it.
However now I run into the problem of its archival nature. Is it possible and or beneficial to gesso the back of the paper after the oil has dried a bit? Would that mitigate issues with rotting of the paper?
Thank you so much,
Raymie.
Hi Greg,
I’ve started painting with oil paints on Arches Watercolor blocks primed with two coats of tinted acrylic gesso.
How can I tell when the paintings are completely dry?
Can I then store the paintings (which are removed from the blocks) horizontally on top of each other?
What should be put in between the paintings?
Can they be weighted to keep them flat?
Hello Ann,
If the oils are not sticky or showing signs of color lift when you touch the surface, then they are probably “dry”. The fact is the oil layers will continue to cure for months and even years. This is even true for thinner layers of paint. It is best to give the paint layers some time to be exposed to light and air before stacking them up and storing them in the dark. A couple weeks to a month should be enough time to have all the paint sufficiently dry on the surface before storing. But this can depend on the colors you have used in the painting. If you have impasto areas that show brushstrokes, they should be hard all the way through before stacking the work. You can press your finger nail into the impasto strokes to see that they are hard dry. When you are ready to stack, you can interleaf the work with glassine or silicone release paper. Tucking the paintings into a normal flat file or portfolio is usually fine to protect them from bending or damage. In case you haven’t seen it, here is an article on dark yellowing, which occurs in oil paintings that are stored in the dark: https://justpaint.org/what-is-dark-yellowing/
Hope this helps. If you have any other questions, we are available at help@goldenpaints.com
Greg
Great article!
I see some comments on priming both sides of the paper. I use fabriano 400 gsm paper, but even if it is a thick paper, it is still fragile. I have not primed the backside as I thought that would prevent the paper from breathing. If gessoing both sides is ok, can I also varnish both sides? That would protect the paper much better.
Hello Staale,
Sorry for the delayed response. Priming both sides of the paper is most helpful for evening out the tension between the front and back. In some cases, it can help the paper warp less when both sides are evenly coated. But it is not necessary if your paper is staying flat after you apply your ground. Acrylics are quite porous, so even if you do coat the back the paper it will still breath. The drawback of covering the front and the back comes with stacking, as the acrylic can stick to itself. If both sides are primed and the pieces get stacked, they can get glued together. You can interleaf the papers with silicone release paper or plastic sheeting to prohibit this from happening.
It probably is not necessary to varnish the back. Doing so might limit your options when it comes to adhering the paper to panel or framing the work in the future.
Greg, what do you think about doing an underpainting with watercolor, on an unprimed watercolor paper, and then (once dired) paint over with oils. The gum arabic of the watercolors would be a barrier between the oils and the paper…?
Hello Gonzalo,
Interesting idea. This could certainly work on a paper intended for oil painting. But, from what we tested and found through historical references, the oil soaks through the watercolor and binds the oil layers to the ground or pre-sized substrate. While the watercolor is not activated by the oil paints or solvents, it does not seem to block the oil from penetrating through. Ideally, the paper is sized with acrylic or another product that will block oil penetration. We will run some tests and report back if we find this is not the case.
Thanks – happy painting!
Greg
Hi Greg,
I’ve been experimenting with oils on Kozo paper that has been well-covered on both sides with Acrylic Gloss Medium (almost soaked and dried). The oil paint mixed with Stand Oil and a little OMS, and in one case using only Liquin, appears to adhere well and does not appear to sink in. I have one such painting from 8 years ago that seems to be doing okay still (no cracks so far), but I know that that is not a long enough time for a proper longevity test. Any advice or comment on the durability of this method would be greatly appreciated since I’d hate for the work to fall apart in the future.
Hi Procheta,
Interesting! We have not tested oils on Kozo paper. Keep in mind that as the oils age, they can become a little harder and will likely need a more rigid support. The works may ultimately benefit from being adhered to a panel or stabilized in some sort of mat and frame. Otherwise, it all comes down to the relationship between the oil paints and the Gloss Medium. We have seen excellent adhesion over the years even on glossy acrylics, but is is better to paint over matte acrylic layers. This provides more tooth for a stronger mechanical bond. Perhaps you could use Matte Medium on the paper instead of Gloss Medium, or use a layer of Gloss Medium to get started then apply a coupe layers of Matte Medium over top to prepare for the oil layers. It is difficult to say how long this combination of materials will last, but if your not seeing any issue after 8 years, then that’s a great start!
Best wishes!
Greg
That sounds good. Best wishes Procheta!
Hello
I’ve been reading these posts with interest. I have done a painting in Artisan water soluble oils on paper in a pad designed for use with acrylics. The painting came out well and I would like to frame it. I see the best idea is to adhere the paper to a board before framing. So, do I use hardboard and PVA glue or something else? Thank you for any advice.
Caroline
Hello Caroline,
It should be possible to adhere the paper to hardboard, plywood or MDO. Whatever is most readily available and you find convenient for your framing application. We typically recommend a GOLDEN product called Soft Gel for this purpose. Here is a video showing how we recommend adhering paper to panel: https://www.goldenpaints.com/videos/applying-paper-to-boardadhering-watercolor-paper-to-panel-using-golden-soft-gel
If this is the first time you will be trying this, we recommend testing with a blank sheet before using your finished artwork. If you have any follow up questions, feel free to contact us at help@goldenpaints.com.
Best wishes,
Greg
Hi Greg,
What a great article and i think i learned just as much from all your responses in the comments.
I have a question – I have some oil stick painting i did on paper a couple of months ago – on unsized paper. Would it be a help to size with Fluid Matte Medium on the unpainted back of the paper? Would that help mitigate some of the future deleterious effects?
Thank you very much,
DT
Hello DT
thanks for your comment! It is a great question for which we do not a great answer. While it is possible to apply acrylic products to such surfaces, we do not expect it to have any benefit in preserving the paper material that has already absorbed the oil. And while it may have some protective qualities for the fibers that have yet to be influenced by the spread of the oil, it is unknown if sandwiching the effected fibers between the oil paint layers and the acrylic layers will make it easier to maintain the work in the future. It may simply be best to frame the work under glass and let it age as it will. OR if you want this work to be a part of the great experiment, and you do end up applying some Fluid Matte Medium or Gesso on the reverse, just make sure to have a note somewhere stating what was done, so conservation might know how to handle the work if it ever comes into their hands. You might also ask this question on MITRA – https://www.artcons.udel.edu/mitra
this is a forum at university of Delaware moderated by conservators and specialists. We looked for similar questions there but did not find an answer. that site is loaded with information! you may have to register to ask a question.
Sorry we could not give a definitive answer, but hope this helps.
Take care,
Greg
Sometimes in the studio, I get going and find myself painting oils on papers that haven’t been pre-gessoed and then at the end of the day, it turns out I like the piece enough to keep it.
However now I run into the problem of its archival nature. Is it possible and or beneficial to gesso the back of the paper after the oil has dried a bit? Would that mitigate issues with rotting of the paper?
Thanks
Hello HR,
I just answered a very similar question so forgive if I simply copy and paste my answer. I know exactly what you mean, sometimes its just too fun painting on paper. perhaps have some Oil Paper around, so when you get the urge you can use that when you want to work in oils:
thanks for your comment! It is a great question for which we do not a great answer. While it is possible to apply acrylic products to such surfaces, we do not expect it to have any benefit in preserving the paper material that has already absorbed the oil. And while it may have some protective qualities for the fibers that have yet to be influenced by the spread of the oil, it is unknown if sandwiching the effected fibers between the oil paint layers and the acrylic layers will make it easier to maintain the work in the future. It may simply be best to frame the work under glass and let it age as it will. OR if you want this work to be a part of the great experiment, and you do end up applying some Fluid Matte Medium or Gesso on the reverse, just make sure to have a note somewhere stating what was done, so conservation might know how to handle the work if it ever comes into their hands. You might also ask this question on MITRA – https://www.artcons.udel.edu/mitra
this is a forum at university of Delaware moderated by conservators and specialists. We looked for similar questions there but did not find an answer. that site is loaded with information! you may have to register to ask a question.
Sorry we could not give a definitive answer, but hope this helps.
Take care,
Greg
Great article and the comment section is also very informative. My question: is it possible to spray acrylic medium over the paper using an airbrush? Would that seal the paper enough to apply oil?
Hi Bill,
Thanks! It depends how many layers you use. We have found that in most cases it requires about 3 brush coats of acrylic product to block oil penetration. A typical spray application is about 1/3 as thick as a brush application. So that is quite a few passes with the airbrush. Also, we have some new recommendations about painting with oils over acrylics. Please read this article to learn more: https://justpaint.org/revising-our-recommendations-for-using-oils-over-acrylics/
As you will see, we are recommending Acrylic Gesso as the primary acrylic product to prepare substrates for oils. We no longer recommend any glossy or matte mediums as sizing without significant modifications to the oil paints when applied over top.
Let us know if you have any questions at help@goldenpaints.com or give a call at 800-959-6543.
Take care,
Greg