How to Prepare Wood Panels – for Painting with Acrylic, Oil and Other Artist Mediums

by | Mar 14, 2017 | Blog | 230 comments

Why Use Wood Panels for Painting

There are many types of surfaces that painters can use for fine art painting. Canvas attached to wood stretcher bars have been used for a long time, and wood panels even longer. Wood is stronger and more durable than the fabric of canvas or linen, and is therefore more archival. Contemporary painting techniques such as pouring paint (i.e. Jackson Pollock) and gluing collage-style are much easier with a sturdy level surface such as wood. (By the way, Pollock did not use wood for his paintings).
Proper preparation of an artist support is essential for producing long-lasting artwork. Raw wood panels need to be sealed prior to priming and painting, to keep moisture from getting to the wood which causes warping and other damage. So once you purchase a wood panel you need to do two important steps before painting: seal to keep out moisture, and then prime to strengthen adhesion between the paint and wood panel.


What’s the difference between hardboard and Masonite

I get asked all the time about the difference between these two terms for wood panels. Click here for a great article that clears up any confusion between the two.


Where to Get Wood Panels

If you are lucky enough to have wood working machinery, you can make wood panels yourself, or hire a carpenter to make them for you. You can also go to any store that sells wood, purchase a sheet of hardboard (they come in sheets 4′ x 8′) and pay them to cut it up for you into custom sizes. The sheets runs about $20 and the charge for cutting will usually be an addional $15 (depends on how many cuts). For a reasonable price, then, you can get a stack of wood panels. Otherwise you can purchase commercially made wood panels from art stores and online artist supply sites. Ampersand makes great panels of good quality. They are the only commercial panel company that I know of that properly seals and primes their panels called Gessobord.  Less expensive versions are available through Dick Blick and other online sites. Commercial panels can come with or without cradled sides (separate wood applied to the panel to add depth to the sides), and with or without coatings (such as gesso or other primers).

I have two issues with commercially made wood panels. I like to work large and in sizes that are not standard. Commercial panels only come in standard sizes, with maximum lengths around 40″ per side. If you want a non-standard size or something larger than 40″ there are not many options. Some commercial companies offer custom panels, but these may take up to six months (no kidding) to get it to you. Commercial panels mostly use hardboard for the painting surface which can get very heavy in large sizes.


Why is it Important to Prepare A Wood Panel

Oil painters must seal wood to stop any acidic oil in the paint from penetrating into the wood support, which can cause wood fibers to rot. While acrylic painters do not have this same issue, sealing is still an important step for using acrylic paint on wood, to eliminate Support Induced Discoloration (SID). SID is a phenomenon that occurs uniquely with acrylic paints. Supports naturally contain impurities that can cause an amber yellow discoloring to any light colored or clear acrylic layer that is applied to the wood unless the support is sealed properly. More about SID on GOLDEN’s website.

Sealing (sometimes called sizing) reduces chances for the wood to warp due to shifts in humidity, and therefore adds an important archival process to your artwork regardless of which painting medium you choose. Sealing also provides an easier surface to apply subsequent paint layers.

Sealers are often confused with primers. A sealer protects the underlying layer or material. It usually needs to be glossy (or non-absorbent) to properly protect the surface by creating a barrier. A primer is a foundation layer that strengthens paint adhesion onto the support. Generally a primer refers to a coating that prepares the surface for the acceptance of paint. Gesso is a primer and not a sealer. Gesso, when applied, has a satin or matte finish, is absorbent in nature, and therefore will not adequately seal the wood unless multiple applications are used – and this still may not seal.

A general rule is to apply at least two coats of sealer directly onto the raw wood to protect the wood. Then over these sealer layers when dry, apply primer to (1) enhance adhesion (2) return tooth to the surface, and (3) whiten the surface for optimizing paint colors applied over it.


Instructions to Prepare Wood Panels

(1) Clean off any dust or debris from all exposed areas of the panel including the cradled sides and panel back, first using a vacuum or air pressure if very dusty, then wiping clean with a microfiber cloth (or other lint free cloth) slightly dampened (with water).

(2) Lay the panel flat on a table, propping it up several inches on all four corners with jars, wood props, etc to allow for wiping away any drips, and ease of application.

(3) Apply a glossy acrylic medium over all exposed wood surfaces. GOLDEN’s GAC100 is made especially for this purpose. It’s special thin formulation of polymer acrylic, applied over the wood, soaks in quickly and minimizes brushstrokes and texture. GOLDEN has recently changed their advice saying that their Acrylic Gloss Medium works better as a seal then their medium called GAC100. I still prefer to use the GAC100 because it is thin and doesn’t create brushstrokes like the Gloss Medium. GOLDEN still says both work fine. You can also opt to use a commercial stain sealer like Kilz found in home improvement stores.

Tip: Let one surface dry fully before flipping over to seal the reverse side. Drying times can vary. When dry to the touch with no tack, it can be flipped over without sticking to the table or other props.

(4) When all exposed wood areas are sealed and fully dry, the wood will feel very coarse. That is because the wood grain gets raised with this first coat of sealer. Lightly sand all surfaces to smooth them using a 220 grit or fine sanding block. There is no need to heavily sand, just an easy swipe with the sandpaper will suffice.

(5) Wipe the surfaces clean with a slightly damp rag after sanding or vaccum, then apply a second coat of sealer. Usually two sealing coats are sufficient, making the wood appear slightly satin or glossy in sheen. Optionally apply more coats if you desire a more saturated seal.

(6) Once you finish applying all sealer coats and it is dry to the touch, I recommend to apply one or two coats of a primer, such as an acrylic gesso, especially to the front surface to regain surface tooth. Priming your panel, regardless of which paint medium you plan to eventually use, will add a second archival process to your artwork, by strengthening adhesion between your first painting layer and the primer. Opt to prime all surfaces, including the back and sides, for a clean white professional look. However, all you really need to do is prime the panel face that will be painted. To summarize you want to seal all exposed areas of wood, but priming can be just applied to the front face.

For acrylic painters, one coat of a better quality gesso, such as GOLDEN’s Gesso, will add adhesion strength between the sealed wood and your first layer of acrylic paint. Lesser quality primers are sufficient for use with oil paint, as oil seeps into the layers differently than acrylic. The lesser quality primer, though, does not have a high pigment content for extra adhesion strength that acrylic paints require.

Once the gesso is dry to the touch it is ready for applications of acrylic paint. To apply oil paint instead, wait 1-3 days or more.

Important: For this blog article I am offering information for fine art paintings that will be stored and/or displayed INDOORS. For information on outdoor projects, such as murals on wood, read this article.  

Additional Information

GOLDEN’s article on preparing panels
Adhesion in Paints and Coatings

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  1. raine

    great information. Thank you!

  2. aarondev

    Acrylic paint is what I use. I work with white hardboard which is available in a painting set website and I bought it from them on amazon.
    I used gac100, which caused the surface to become granulated, which had never happened previously, and then I used gesso.
    When I first started painting, the entire surface began to peel away, and I was able to take off the entire surface of my board. Are you able to assist?

    • Nancy Reyner

      Hi Aaron,

      I’m sorry to hear of your issue with the white hardboard and your acrylic coatings. I am not familiar with the white hardboard and wonder what they are using to coat it white, and also if the company adds a sealer coating over that. This is important information that will help you figure out what went wrong. If the GAC100 became granulated it could be three things. It could be that it is not compatible with whatever coating is used with the white hardboard. Did you clean the hardboard with denatured alcohol or at least wipe it with a damp rag? This could help because possible in handling and transport the board got dust particles on it that combined with your GAC100 to granulate. The third possibility is that you applied the GAC100 to a cold surface in a cold room. Acrylic can granulate if it is too cold when applied. I like to keep my studio at 60 degrees or more especially in the winter. When you say that the entire surface peeled away I’m not sure if you meant the white of the white hardboard too? If so, then the hardboard is defective. If you meant that it peeled away between the GAC100 and the white board, then that indicates there is some type of incompatible coating over the white hardboard that resists water-based mediums. Hope this helps! I recommend contacting the company that makes the hard board to ask them about their coatings, and also about your issue.

  3. Amy

    I have a very dry raw 4 foot piece of wood from a cut tree at my cottage. I want to make a WELCOME sign but cannot recall the name of or what I need to use BEFORE applying a Primer. Can someone give me a hand and let me know? I’d really appreciate it as I’ve been googling with no luck. Thanks!

    • Nancy Reyner

      I would use Kilz stainsealer primer on the raw wood, and then just paint over it using commercial paint products. If it will be out doors you don’t want to use fine art products.

  4. Clint Davis

    So here is a practice piece I’m in the middle of doing, using two coats of GAC100 like you suggested and I’m very happy with the results!

    • Nancy Reyner

      Thanks for posting your painting Clint! Looks great and I’m glad the sealing process worked for you.

  5. Cindy

    Thank you for addressing this topic! I do have one additional question. If I’m adhering a piece of art done on yupo is this process still just as important?

    • Nancy Reyner

      Hi Cindy,
      Yes this process is important. The wood panel needs to be sealed on all places where it is exposed. If moisture enters the wood panel it can warp. If you are adhering something onto the face, I would still seal it first. This has an advantage for gluing because when you apply glue onto an unsealed surface, the glue can seep into the surface quickly, and cause issues with your gluing process.

  6. Marisa

    Great article! This was very helpful, as I am planning on doing acrylic painting on small wood slices to make pet portrait ornaments. I was wondering if it is important to varnish your painting once it is finished? If so, what do you recommend as a varnish for an acrylic painting on wood?

    • Nancy Reyner

      Hi Marisa,
      Varnishes are a great way to keep your painting looking its best for longer. You don’t have to, however, varnishes will protect paint colors from fading, and they will also help protect the paint from getting scratched while being handled. I like to use Golden’s Polymer Varnish. It comes in different sheens such as matte, semi-gloss, satin and gloss. I usually use gloss because that brings luminosity to the colors and keeps the contrast in the work strong. This varnish is a fine art varnish. This means it has two important qualities that are not found with commercial varnishes. They have UV protection (keeps the colors from fading) and is removable. This removability is important with fine art paintings because if they get dirty or something happens to the surface, they can be easily removed and replaced with a new clean varnish coating.

  7. Christina Fasciana

    Great blog!! Answered so many question I had about using a plywood sheet as a base or canvas. Just wondering can I use the whole 4′ x 8′ sheet for one project without cutting it? Thank you for your creativity and knowledge.

    • Nancy Reyner

      I would think that you definitely can use the whole 4′ x 8′ sheet. You would need to brace it on the back so it doesn’t warp. Even with sealing all areas of the raw wood, you would need to stablilize it when it is that large. Any side that is 40″ or more should be braced on the back. You would also need to finish off the edges for a clean look, unless it will get framed.

  8. Lynne M Connor

    AMAZING ARTICLE. Super helpful and easy to understand, with useful links and GREAT HELPFUL COMMENTS. Thanks so much Nancy!

    • Lynne M Connor

      Lynne again. :). I am not an artist, just a dabbler, but LOVE TRYING. A project I am investigating is painting designs on the tops/ runners of wooden stairs. After researching a bit, I have decided to paint panels, not stairs, since the stairway is in frequent use (too much down time). The panels would be affixed to the stairs (hopefully – ha)
      For such high traffic surfaces, what would you recommend for preparing the panels – and for the panels themselves? My thoughts are below – could you please see if anything looks way off the mark? Thank you!
      1. purchase sheet (hobby store), pieces cut to size.
      2. prep. panels prior (sand/ seal/ prime)
      a. Sealer = GAC 100? Both sides of wood sheet? Number of coats?
      b. Primer = White or Black Acrylic Gesso? Number of coats?
      3. design applied w/ acrylic paints – I have random acrylics – likely student grade. Should I purchase new or will anything work? Some articles recommend brands; Folk Art, Apple Barrel, Golden.
      4. seal post painting. Miniwax – Polycrylic protective Finish? Number of coats?
      Am I insane on embarking on this project and is it doomed to certain failure? Ha. Thank you so much for your time. I really appreciate it!

    • Nancy Reyner

      Hi Lynne,
      For use on stairs I suggest using commercial products that are made for high traffic and frequent use, instead of any fine art products. Looking at your steps, they look good. For step 2 instead of GAC 100 use commercial sealers like Kilz. Follow instructions on the Kilz container. This will work as a sealer. It may work as a primer too. Again, the can label should tell you if you still need to prime over it. If you do use a commercial primer, not fine art products. Seal (and prime if a separate step) all sides of the wood. Even if you are gluing the backs of the panels to the stairs it’s good to seal so the glue doesn’t seep into the wood quickly which means it won’t be present enough to glue. Black or white priming doesn’t matter – it’s up to you as a preference for how you want your colors to show up – bright or darkened. Your paints will last according to the quality of paints you select. Cheap student grade will probably peal off, flake off or fade. They will do this with artworks on the wall and especially under foot on a stairs. Here I would use a good quality acrylic paint like Golden. (So this would be the only place to use fine art products is the paints with high quality pigments and a good quality acrylic binder). Golden is the best in my opinion because they are committed to only use high quality ingredients in all their products. Final seal should be something that is meant to use for wooden stairs. You do not want anything that would be slippery. Go to a high quality furniture or wood working site or store and ask for the best sealer for wood stairs. You would follow directions on that product’s container. You ask if sanity is in question. Hmm….good question. I don’t think it is doomed to failure. My only concern is the danger of causing someone to slip. Also can anyone really see your painting as they are using the stairs? Would it be a good alternative for you to do an painting on panel, then frame it and hang it on the wall opposite the top stair? By the way, there are oil cloths you can paint that create floor mats or floor rugs. These are meant to not slip and are also created for high traffic. I suggest looking up painted oil cloths for floor mats. This isn’t my forte but I’m sure you will find some good information online from those that work this way. Good luck and feel free to post again if you find any good information out to share.

    • Nancy Reyner

      You are most welcome! Glad you liked the article.

    • Maribeth C. Yarnell

      Lynne M Connor, STAIRWAY SOLLUTIONS:
      I painted the RISERS [lift-faces] of several sets of stairs in an old building housing an antique store. My prep was thorough and final sealing was with a polyurethane wood floor sealer. This way, the art was always visible. The community even brought TOURS to see it! [store considered it free advertising, and nominated me for a community award, although they paid for the project!]
      Also, only larger-shoes would have toes banging the risers, so I kept the interesting parts of my designs in the upper 5 inches of 7 inch risers, leaving most of the bottom 2 inches stained wood color and thoroughly top-coated which also kept the overall thickness of the coatings+paint at the same thickness over the full 7 inches – no little elevation-demarcations to promote lifting.
      My art is still working for the building, and they have re-worked the tops of the stairs with polyurethane several times in 7 years … tons of foot traffic.
      Apologize if this is [probably] too late to be of real use for your project, but had to share, just in case….

    • Maribeth C. Yarnell

      LYNNE – P.S. One problem with graphics on the TOPS of steps is that in going DOWN, there can be optical-illusion-istic reactions, causing some folks to misstep … depends on the graphics, of course.

    • Nancy Reyner

      Thank you for your comments! I think these will be very helpful to Lynne.

    • Ecbatana-MC Eagleturtle-Yarnell

      P.S. One problem with graphics on the TOPS of steps is that in going DOWN, there can be optical illusion-istic reactions, causing some folks to misstep … depends on the graphics, of course.

  9. Nancy

    I have an old painting on plywood that was painted in acrylic paint – but not sealed or primed originally.
    1. Can I sand it smooth – but not down to the wood surface and then seal and gesso it? Will that work – then repaint it with acrylic paint?
    2. I have painted on several cradled purchased painting panels and have NOT sealed the back side. Do I need to go back and do that?
    3. I have sealed with matte acrylic medium…does it need to be glossy? and if so how does that work? as my understanding was that the medium is made”matte” with addition of talc or other fine powder.
    I really appreciate your help. Nancy

    • Nancy Reyner

      Hi Nancy,
      1. Yes you can sand it smooth leaving some of the original acrylic paint left on there, then overpaint. You don’t have to seal the face because the remaining acrylic paint will act as a seal. You may need to seal the back and sides, though.
      2. If raw wood is exposed it can still absorb moisture from the air which causes warping. To be extra safe it’s always good to have any raw wood that is exposed, sealed.
      3. Yes a sealer must be gloss to create a good barrier as a sealer. Matte means it is absorbent, so you are actually encouraging the wood to absorb moisture by adding a matte product on it. First seal it with a gloss medium. Then if you don’t want the gloss sheen add another coating of the matte.

  10. Lauren Schade

    I have purchased an artwork that is on a thin wood panel (MDF i believe) and I want to ensure I display it properly and preserve it. It hasn’t been mounted on anything it is just the wood on its own. Should I do something to prevent it from warping and how can I protect it?

    • Nancy Reyner

      Dear Lauren,

      It’s good you are taking care of your art! It looks like a beautiful painting in your photograph. Sealing the back is a good idea to make sure moisture doesn’t enter through the back, which would then cause warping. In the article I make a distinction between a primer and a sealer. A primer is absorbent and allows moisture to penetrate it, while a sealer acts as a barrier and doesn’t allow moisture to get to the wood. Make sure you pick something glossy and that is your best tip it is a sealer. You can use any regular acrylic gloss medium. Avoid specialty mediums such as pouring mediums or gels. I like Golden’s Gloss Medium for sealing.

  11. Wood ship kits

    That’s really nice post. I appreciate your skills. Thanks for sharing.

    • Nancy Reyner

      Thank you for your comment! Glad you liked the post!

  12. Helen Ayres


    I don’t know of this is a language thing. You keep saying hardboard, do you mean *plywood*?

    I always thought wood panels were made from plywood – or Birchwood – I think it’s called in America.

    Hardboard is something quite different made from exploded wood fibre, isn’t it?

    • Nancy Reyner

      Hi Helen,

      I agree art terms can get confusing. Plywood is a specific type of manufactured wood, and so is hardboard, but they are different products. Hardboard used to use the name Masonite, but that is a manufacturer’s brand name for hardboard. Masonite is no longer available as that company has closed, so it’s better to use the term hardboard. I suggest reading the article about hardboard vs masonite by Ampersand linked above and in my blog article. It explains it better than I can.

  13. Jan

    Hi Nancy,

    Great article.

    Can you use any gloss medium to seal or only Golden? I am working with a pine panel and want limit the appearance of brush strokes, so will sand between layers. Also what would you recommend to seal the finished panel?


    • Nancy Reyner

      Hi Jan,

      If you use any gloss medium to seal over imitation gold leaf you risk tarnishing. The copper component in imitation gold leaf will tarnish two ways – direct contact with air, and also with ammonia. Ammonia is in ALL water-based acrylic products (paints, mediums, varnishes). The ammonia dissipates completely from the acrylic once the acrylic is dry to the touch. Ammonia will tarnish imitation gold leaf ONLY when it comes into contact WHILE WET with the leaf for a certain amount of time. If you use solvent based acrylic sealers you will have no problem with tarnishing whatsoever.

      There are some people that cannot work with the toxic solvent based sealers. There is an alternative which will work, but has two downsides – it is tricky to apply correctly, and needs multiple coats to create a strong enough seal. Golden’s GAC200 is the ONLY medium I know of, that when applied – correctly – dries so fast it dries before the ammonia can tarnish it. The tricky part is that this product still has ammonia, so if you apply it too thickly, or add water, you will tarnish the leaf. If you overbrush this fast drying medium it can create a permanent whitish film. If you must use a non-toxic sealer, then this is the only one I can recommend. I suggest experimenting applying it before putting it on something valuable. To seal the finished panel I recommend using an archival varnish. If the leaf is properly sealed (and you haven’t sanded off the sealer with your process) you can safely use a non-toxic varnish such as Golden’s Polymer Varnish Gloss.

      Here is an article I wrote with more information about sealing vs varnishing along with gold leaf that you may find helpful.

      I hope this helps!


  14. Mina

    Hello Nancy,
    Thank you for the great articles!
    I was wondering if gac 100 could be used as both a sealer and a primer on its own, as suggested on the Golden website (“GOLDEN Fluid Matte Medium, Matte Medium or GAC 100 (for acrylics) will all work well as clear “gessoes” to allow the look and texture of the canvas or other support to show through”) ?
    If I were to prime a linen canvas instead, should I still seal the backside with gac 100? And should I sand the canvas between each coat?
    Thank you in advance for your help!
    Kind regards,

    • Nancy Reyner

      Hi Mina,

      A sealer is different than a primer. Much different. Sealers are glossy and non-absorbent and keep one layer separate from the next. Primers are pigment loaded to create a coating that adds adhesion strength, meaning it allows one layer to seep into the previous one for extra sticking power. Basically, there is no such thing as a “clear gesso” even though there are products sold with this name. If it is clear, then it is a medium, not a primer, and it will coat a surface – which makes it a selaer not a primer. I know I’m being a stickler with details here, but I feel it’s helpful to know why you apply a certain product and what benefits it is meant to do. Your biggest tip is that pretty much anything glossy will seal, and anything matte or satin will absorb. A good rule of thumb even though there are exceptions. GAC100 is glossy, it is a medium, so it will seal wood or layers of paint. It is not a primer and won’t help adhesion if that’s what you’re looking for. Applying GAC100 on the front and/or back of linen canvas will seal the canvas. It will allow your paint to sit on top of the surface instead of soaking in. Your paint will stay wet longer and your canvas will be protected from moisture entering from the back – so good thing to do. If you apply it with a smooth brush, using several coats, it is a thin enough product that you probably won’t need to sand it to remove brushstrokes. Again, you can very well seal your canvas and SKIP priming altogether if you don’t want to cover the canvas with white. Using a “clear gesso” is a way, in my opinion, to get people to buy a product that is not needed.

  15. Heather

    Hi Nancy, Thanks for the great article. Two questions for you. I’m preparing some birch plywood panels for painting and used GAC 100 as a sealer. I have one coat on so far. I plan to gesso the front of the panel. Do I need to sand between the two gessoed layers?

    Question 2 is that I have a painted canvass that I want to mount on another plywood panel. Do I seal the panel first and what is the best adhesive to stick the canvas to the board. Thanks so much!

    • Nancy Reyner

      Hi Heather,
      No you do not need to sand the GAC100 in between coats, regardless of what you will put on top of that coat – another GAC100 or Gesso or paint.You also do not need to sand between gesso layers. Acrylic loves to stick to itself. So that means any acrylic product – paint, medium, sealers, primers – can all be layered one over the other without need to sand to provide extra adhesion.

      Always seal wood panels regardless of what you will be doing next to it. The wood should always be sealed so that moisture does not enter it to possibly warp it. So for your second question, you can mount the painted canvas onto the plywood panel, after the panel is sealed all over. I like to use acrylic Gloss Gels for glueing almost everything. I use Golden’s Soft Gel Gloss for lightweight items to adhere, and move up to Regular Gel Gloss, or even Heavy Gel Gloss for heavier materials. Hope this helps!

  16. Faizan Shiakh

    Hello, the blog was excellent and is worth reading. Thank you for sharing the post. This is a very Impressive Blog everything is explained with details and easy to understand, even the prices are given where many people get stuck because they don’t know how much will things cost them will they go out budget or not, and the instruction is elaborated in such a good way that I read the whole thing and found it very easy to understand.
    Thank You For Sharing It.

    • Nancy Reyner

      Hi Faizan,
      I’m glad you liked the post. Thanks for your comment!


  17. Colleen

    Hi Nancy, I painted some images on an old oar that I sanded but the surface is old. I used acrylic but had to use Deco Color paint markers also. Idid not treat the wood prior. I have Golden varnish matte, should I use this?

    • Nancy Reyner

      Hi Colleen,
      Sounds like a very cool project using old oars. If you sanded the oars prior to painting, then you will have good adhesion between the paint and wood. I don’t think the age of the wood will make a difference. What can cause an issue, is if the oar was painted with an oil-based paint, and then you applied water-based over it. But I don’t think you’ll have a problem, because you sanded it first. There is an issue about needing to seal the wood, and this can take place after you finish painting, as well as prior to painting. Now that the oar is painted, if you varnish it on all exposed areas (so everywhere – painted surfaces and unpainted surfaces like the back and sides). You can use any varnish. However, I highly recommend you first coat the whole oar with a clear glossy medium. Golden recommends using a mixture of 1:1 Soft Gel Gloss and water. They call this an isolation coat. If you apply the matte directly over the painted oar, you may risk a big problem. Matte and satin varnishes contain a white powder. If you apply the varnish over any absorbent (seen as matte) surface, the varnish will sink into the surface leaving the white powder sitting on top. This is not fixable. So first apply the isolation coat. Let it dry. Now apply one coat of a gloss varnish. Let it dry. Then apply the matte if you don’t want it as shiny. When the matte is applied over the gloss it will not create any issues.

  18. Megan Coppola

    Hi Nancy, Thank you so much for this detailed article. I found it while searching how to prevent my wooden canvas’ from cracking/warping. If I’ve already completed an acrylic painting is there a way to seal it afterwards? I understand that it would have been best to put a barrier between the wood and the acrylic – but I’m hoping all isn’t lost! Additionally I have another entire set of wood canvas’ that only have one base layer of acrylic paint on them – do you have a recommendation on how to move forward with these ones? Thank you again!

    • Nancy Reyner

      Hi Megan,
      No worries! You can definitely seal the back and sides of your wood panel if they are still raw. Your acrylic painting on the face will act as a seal and will keep moisture from getting to the wood from the front. The sealing coat between the wood face and your first layer of paint will help to keep any staining. But this happens right away, within minutes, so if your painting is finished and you don’t see any yellowing then all is fine. The yellowing only happens while applying the wet layers. By the way, I am assuming when you write “wood canvas” you are referring to a wood panel – an all wood painting surface? If not just let me know. You also asked about your newly started panels that only have one base layer of acrylic. The staining only happens when you apply thick layers of acrylic, or many layers of thin acrylic. The stain is only visible when you have areas of white or light colors. If you will not be using acrylic thickly, or will not have any light areas (usually we do have light areas) then you don’t need the stain sealer coat. If you want to play it safe, you can easily apply a coat of gloss acrylic over your base layer. Then this will keep any staining from moving into subsequent layers. Hope this helps answer your question.


  19. Sally Jacobson

    Hi Nancy,
    Thank you for all the information. I am using birch cradle boards as the substrate for my mixed media cyanotypes on paper. I will use the Golden GAC Sealer you have suggested. I would like the edges and a tiny bit on the face if panel to be white or possibly another color. Should I just use gesso for this ? Then I must adhere the paper artwork to the panel (another dilemma, dry mount with fusion 4000 or some sort of glue). But then do I varnish? And with what? So many questions! I’d appreciate any guidance you can give.

    • Nancy Reyner

      Hi Sally,
      Birch is a great wood for painting supports. You can use Gesso for your white on the sides and front, where you will eventually adhere your cyanotype. It’s fine to have the Gesso exposed. You can also apply an acrylic color instead of the Gesso, or over the Gesso. Gesso tends to be rather matte, so I usually paint over it with an acrylic paint. The paint’s sheen is usually semi-gloss and easier to clean if needed. When you adhere paper to the panel you can use any acrylic gel. Gels work better than mediums. Gels are thicker, but you can apply them thinly (not diluting them, just applying them thinly) and then they stay wet longer, reducing the risk of wrinkling the paper. Now to the issue of varnishing. If the ink is watersoluble you will need to spray a solvent-based varnish (like Golden’s Archival Gloss Varnish Spray) over the print. If it is not water-soluble (please test this first to make sure) then you can still spray the same varnish I just mentioned, but you also have the option of brush applying a non-toxic varnish such as Golden’s Polymer Varnish. If you plan to frame it behind glass when finished, then you do not have to varnish. I like varnishing because the varnishes I use (and the ones I just mentioned) have a UV protection in them. You can use glass with UV protection but those are expensive, and it’s fairly easy to varnish. Hope this helps answer your questions.

  20. paul b

    Great article!
    Do I varnish or seal my cradle on the back of the board?

    • Nancy Reyner

      Hi Paul,
      Glad you like my article. Sealing and varnishing are different terms for different processes. I know sometimes art words get confusing. A wood board needs to be sealed ALL over – sides of the cradle, back and front. Use any gloss acrylic medium for this. Gloss is non-absorbent, so it will seal and won’t absorb. Matte products are absorbent and will encourage absorption. So sealing is done in the beginning prior to painting to protect the wood from absorbing moisture and possibly warping from that. Varnish is usually applied as a final coat to protect the PAINT. It has UV protection so it keeps the colors from fading. It is removable (fine art varnishes should be removable) so it can be cleaned if needed, as all paint will collect dust into its layers. If there is no varnish applied it will not be able to be cleaned. A painting is cleaned (as in museums) by removing the varnish that may have collected dust and applying new varnish. So you would not need to varnish the cradle sides or panel back. Hope this answers your question!

  21. Juel

    Hi Nancy, thank you for this detailed guide. I unfortunately started prepping my panel with gesso. Should I sand it down and apply the acrylic medium? Or apply it over the gesso as is?

    • Nancy Reyner

      Hi Juel,

      You can apply the medium directly over the gesso. It will still do the job of sealing the wood to keep out any moisture and to reduce risk of warping. No need to sand down the gesso. After applying the medium you can apply the gesso again, so you get the benefits of the gesso adding adhesion strength between the first paint layer and the surface.


  22. Glenda Hopkins

    Hi Nancy, great clear information- thank you. I’m wanting to explore using boards but was wondering if I can use graphite and ink on these boards?

  23. Felicity Perkins


    I came across your how to blog and love it!
    I’m from the UK and am looking to give this a try
    I just wondered what sort of pen you have used here before applying the primer and resin? Is it an oil based?
    I’m aware some wouldn’t work and would end up running.

    Many thanks

    • Nancy Reyner

      Dear Felicity, I am happy to answer your question, but am not sure what you mean by “pen”? And there is no resin used in my process as described in this article. Please feel free to add more details to your comment post here and I’ll get back to you as soon as I can.

  24. Chloe


    I’ve just completed my first ever acrylic painting on wooden panel and loved it! Following the steps above for preparation.

    I’m just curious as to how you would tidy up the back of the panel to prepare it for hanging?

    There’s a few paint marks on the back and as it’s for a customer I want it to look as tidy as possible 🙂 x

    • Nancy Reyner

      Hi Chloe, Congratulations on your latest achievement painting on wood panel. The backs of my paintings are handled the same way I do the fronts and sides. So while I prepare the panel, and before painting on it, I seal all exposed areas of wood including backs and sides. Then I prime all the same areas with white Gesso. I use two coats so it looks pristine white all over. Then I add my painting on the front. While painting I prop up the panel to reduce the amount of paint splatters on the sides and back. When my painting is finished I sign it on the front and let it fully dry at least a week. Once dry I flip my painting over onto foam to protect it, and touch up the sides and back with more gesso in case paint got splattered on them. I add the hardware and a tag listing the materials used on the back. I will also add my signature on the back too. Then lastly I flip the painting face up, wipe it with a damp rag and varnish it.

  25. Qaiser Shahbaz

    Hi Nancy !can i use water with acrylic gel medium for acrylic painting or I should use only the gel medium for acrylic painting?

    • Nancy Reyner

      Hi Qaiser! This is an excellent question! I have a video about this that will best answer your question. The quick answer to your question is YES of course you can use water and mediums to change your paint accordingly to create different effects. If you don’t use water you will be missing out on ways to make the acrylic act and appear like watercolor. Here is a link to the video I mentioned:

  26. Bo

    Is there a clear sealer for wood if it won’t be completely covered with paint? I will be using acrylics

    • Nancy Reyner

      Hi Bo,

      Sealers are usually clear. It’s the primers that have a high load of pigment to add adhesion strength. Sealers I use such as acrylic gloss medium, and GAC 100 are both clear. If you want to make sure the wood grain is still visible prior to painting with acrylic, then skip the primer (Gesso) as that is usually white and will cover the wood. Products called “Clear Primers” are merely acrylic mediums as I mentioned before.

      Hope this helps!


  27. Daniel


    My ten yer old daughter and I are making Indo boards (smooth plywood)…we want to have small ocean designs, like a graphic turtle that will be painted on them but the rest of the plywood we want to appear natural. They will be finished with clear lacquer (I’m guessing)). What kind of paint would you recommend we use and lacquer? Thank you!

    • Nancy Reyner

      Hi Daniel, Sounds like fun working on a project together with your daughter. Since you will be using the Indo boards, you will want to use commercial grade (instead of fine art grade) paints and sealing products that will protect your board and painting during regular wear and tear with use. I recommend sealing the wood with a good grade polyurethane or lacquer that you can find in Home Depot or commercial paint stores. Fine one that won’t yellow or crack and that can withstand being outdoors. Even if you don’t plan on having it outdoors, that will mean you will be giving it maximum protection. Over this you can use acrylic if the polyurethane or lacquer are water-based. If not, and they are oil-based, then you would use oil paint over it. After painting apply another sealing coat using the same product you used to first seal the wood.

  28. Janna Aycock

    Thank you for this wonderful information. I am actually painting a large piece of plywood with a Christmas scene using acrylic paints. After priming and painting, what do you recommend as a final step as a sealer once the painting is complete?

    • Nancy Reyner

      Dear Janna,
      If the painting will be outdoors you will need a commercial sealer such as polyurethane. If the painting will remain indoors and you want it to last a long time, I suggest you seal it like you would a fine art painting. You would first apply what’s called an isolation coat. This is a mixture of 1:1 an acrylic gloss gel with water. This will make the painting all glossy so that the final top coat of varnish that goes on next, will sit evenly on top. For a final varnish you can use an archival varnish meant for paintings. These have UV protection and are removable for cleaning purposes. Those two qualities are what makes the varnish archival. Most varnishes come with options for sheen as gloss, matte or satin. I suggest Golden’s Polymer Varnish Gloss. This varnish is non-toxic and can be thinned with water. Using gloss brings out the colors more than using a satin or matte. Hope this helps!

    • Eileen

      One have 2 panels make from slats of wood that were commercially painted or printed (airplane image). It’s a thing layer. There are spaces between the slats. I want to paint over this. Does it still need priming? I can feel the texture of the wood.

    • Nancy Reyner

      Hi Eileen,
      I think I understand your question, although not sure what you mean by a “thing” layer. I’ll get it a try based on what you wrote. Sealing is important to keep moisture from being absorbed by raw wood. When moisture gets absorbed the wood may warp. Sealing is recommended on the back and sides as well as the front. You mentioned the front is already painted or printed. So here’s where it gets tricky. You don’t need to seal the front because the paint or print already applied will keep moisture out. If the paint or print is thin and the wood looks matte or still raw, then it does need to be sealed. The tricky part is that you need to use a sealer that is compatible with whatever is used for the paint or print. Since it probably isn’t possible to find out what the paint or ink is, then to be safe you would need to use a solvent-based or oil-based sealer. If you want to paint OVER the images that are pre-painted, then you can use a combination sealer/primer which will be opaque and will seal as well as adequately cover the painted image.

  29. Lydia

    Thank you, Nancy! The differentiation between seal and primer was super helpful!

    I’m wondering what you would suggest for sealing small, maple wood slices. I will be painting them with oils for indoor use. I already have a commercial linseed oil, so would that be a good option or would you recommend something different? I don’t mind if the seal darkens the wood as long as the grain is visible.

    Thank you for your time,

    • Nancy Reyner

      Dear Lydia,

      Best sealers are gloss acrylic. Oil isn’t really a sealer. It will sink into the wood but won’t keep out moisture – which is the main purpose of a sealer. I recommend not using linseed oil as a sealer. It is fine for use with your oil paints, to add to a paint color to make it more transparent. Instead use any acrylic gloss medium or gel, either straight or adding some water to thin it. These should not darken the wood, even though that is not an issue for you. Once sealed with an acrylic gloss medium you can overpaint with your oils.

      Enjoy your project!


  30. Kim Walker

    Thank you Nancy! Over twenty years into my art making adventures and every time I read one of your blogs I learn something new and helpful and find lots of inspiration!

    • Nancy Reyner

      Dear Kim,
      What a lovely note! Thank you so much! I’m very glad you are finding my articles helpful for your work.
      Thank you!

  31. Mei

    Thank you for an excellent explanation of how to star painting on wood. Do you have any advice on how to varnish an acrylic painting on wood to give it maximum protection? I am planning a piece on wood box that will be handled frequently.

    • Nancy Reyner

      Dear Mei,
      If the piece will be well handled as you said, then I suggest using a commercial grade varnish or sealer. Home Depot, Walmart or other paint suppliers all carry clear gloss sprays that should work well. You can also use a polyurethane. Any type of clear sealer should be fine. You probably do not need to use fine art varnishes as these are archival and are removable for cleaning purposes. These are well suited for fine art paintings that will not be handled.

  32. Dilsah

    Hello Nancy
    Such a nice comprehensive article.
    I want to paint with ink and watercolours on wood.
    Is it the same process ?
    Thanks for your help

    • Nancy Reyner

      Dear Dilsah,
      I’m glad you enjoyed the article. The process I describe is to seal the wood so it doesn’t warp. Warping will happen when moisture enters wood. By sealing the wood with something that is glossy you keep moisture from entering the wood. This can happen with or without painting on top. So sealing is important regardless of whether you will paint on it, leave it as is, or paint using ink, watercolor, acrylic or oil. Priming would be an additional step, after sealing, that would be beneficial to painting with any type of paint. Priming would add adhesion strength between the first layer of paint and the primer. If you are using ink and watercolor you would want to prime to get an absorbent surface, so that the paints will adhere well.

  33. Ellen E Baer

    Thank you for such detailed information. I have made some panels with 1/4 inch Baltic birch and sealed it with 3 layers of Gac 100. The panels are cradled but, they are warping a bit and the grain pops out with each application of gesso. The gesso Michael’s house brand. Do you have any advise that would fix these problems.

    • Nancy Reyner

      Dear Ellen,
      Sealing it with three layers of GAC 100 should keep it from warping unless the wood wasn’t cured before making the panels and still contains moisture. Another reason for warping would be if you diluted the GAC 100 you applied. The medium can be accidentally diluted by using a wet brush, or not stirring the product prior to use. I am assuming you sealed the wood on all exposed surfaces including the back. If not, then this could also be a reason for warping. If the grain is still expanding with applications of Gesso this may indicate that somehow your three coats of GAC 100 are not sufficient, or not applied correctly as per the reasons I mentioned above. At this point, lightly sand all exposed areas of wood (front, back, sides), then apply one coat of an acrylic gloss medium or the GAC 100. Both will work as long as they are not diluted with water. Hope this helps!

  34. Patricia Truitt

    I used run off paint from an acrylic pour to paint my wood. Must I still prime the wood?

    • Patricia Truitt

      I should add that I used the run off several days ago so it is indeed dry. And, I plan to do another acrylic pour. Thank you.

    • Nancy Reyner

      Hi Patricia,
      You can use anything to paint on wood. HOWEVER the most important thing to remember is that wood needs to be SEALED prior to adding anything. Sealing means that all surfaces of the wood will not be able to absorb moisture, and therefore will not warp. If you use any paint or product that is GLOSSY it will act as a sealer – or barrier for moisture entering into the wood. If you use any paint or product that is MATTE, this means it is absorbent, and therefore you are actually increasing its ability to absorb moisture, and therefore may warp the wood.

      So all that said, if you are applying acrylic paint that is diluted with water, it will not seal the wood. If you are adding acrylic paint that has mediums added to it (such as is often added into pouring mixtures) then you could very well be sealing the wood. Are you also sealing the sides and back? If not, these need to be sealed too.

      Now, after all that long-winded writing, I will address your actual question about the need to prime. The reason for my rambling is that many artists confuse the products and functions of sealing with priming – and they are very different. Priming usually uses Gesso – which is matte, and absorbent, and this is important because the main function of priming is to add adhesion strength between surface and the first paint layer applied. Adding a primer (over a sealed wood surface) is not necessary but can add an important element to your layering. Here’s a good test. If your first layer of paint (you are using your run off paint from a pour) is thinly applied, or thin in consistency it will probably adhere well to the sealed wood. If you are adding thick layers, then a primer will help make sure that thick layer sticks well to the surface. The decision to skip an important step like priming really depends on your surface and the quality (consistency, dilution, application, etc) of your first paint layer. Hope this helps!

  35. Cat

    Hey there Nancy!

    I loved this article, thank you so much for writing it!

    I have a question I’m hoping you can answer. I’ve read through your comments and didn’t see this question posted so hopefully this isn’t a repeat 😬

    I am very interested in painting yard decorations on untreated dog eared fence or wood from pallets. I am an acrylics fan so that will be the type of paint I use.

    My question is this; would I still follow the directions above if my project will be outside and exposed to the elements?

    I know you provided a link to follow for outdoor projects but that page seems to be geared towards painting on masonry or the sides of buildings which isn’t really the type of surface I plan to paint on.

    It even has a table that’s supposed to tell the reader what steps to take for each material that is to be painted on but I’m struggling with some of it. I’m sure I’m overthinking it but can you break it down for me please?

    Any advise is greatly appreciated!

    • Nancy Reyner

      Hi Cat,

      Sounds like you have some fun projects in the works. If you are going to paint on raw wood and want it to last outdoors, you will want to use commercial products meant for outdoors not fine artist products. Use sealers and paints made especially for wood outdoors such as those used for porches and fences. The article I referenced on Golden’s site has some good information. You could skip filling in the cracks to create a smooth mural surface if that isn’t important to you. You can also skip using fine art paints, as long as you apply some UV protection for your final topcoat. See if you can find a commercial topcoat (try Home Depot or paint stores like Sherwin Williams). See if anyone working there can find a topcoat product with UV protection to keep your colors from fading outdoors in the sun. Wood is pourous, which means just about any sealer, paint and topcoat will adhere. You want to make sure you get UV protection somewhere in those layers, and also the topcoat is weatherproof, waterproof and as durable as you can find. Hope this helps!

    • Robyn

      Hi nancy,
      Im a new artist.
      I actually think that’s the first time ive ever referred to myself as an artist.
      And i dont think i’ve ever commented on a post in my life. But i see this is a recent post.
      I also have to agree i am grateful for your articles and your artwork is beautiful.
      I originally found you when searching for gold leaf info.
      Ive been asking art retailers, hardware stores, renovationists etc, but i have yet to ask a fine artist. Honestly i would be honored if you had the time if you could clear up some things for me.

      – can i use a zinniser stain blocker or kilz WITHOUT gesso ( if its matte & water base) for sealing & priming for acrylic paints?
      – can gloss modge podge or frank t. ross wellbond universal sealer be used as an effective sealer?
      -can pouring medium be used as a sealer and top coat?
      – can gloss medium & varnish be used as selaer and top coat?
      – what do you recommend to varnish mdf and birch ply?

      I found your article very well laid out.  I am new to wood and teaching myself and still get tripped up. But happy 🙂



    • Nancy Reyner

      Dear Robyn,

      Thank you for your comments. I’m glad you are finding my articles helpful for your work.
      Here are some answers to your questions.
      1. I am not familiar with Zinniser Stain Block, but have used Kilz. Kilz is both a sealer and primer, so yes you can use Kilz without gesso for overpainting with acrylic paints.

      2. I am not familiar with Modge Podge or Frank T Ross. Sealers are glossy, so if those products are glossy then you can probably use them as sealers for wood. The idea is to seal the wood so no moisture enters it and to keep it from warping.

      3. I would definitely not use pouring mediums that are meant for pouring as a sealer. Sealers should be thin so that they penetrate the wood. Pouring mediums are usually too thick to do this effectively. The word “topcoat” is easily misunderstood or used in the wrong way. Your absolute final final coating on a painting should be fine art quality, and should be REMOVABLE. Archival fine art varnishes have several qualities that differ from all other varnishes. They have UV protection to keep colors from fading, and for conservation purposes can be removed so the painting can be cleaned, and then the varnish is replaced. Pouring mediums are not removable and have no UV protection. Pouring mediums can be used as your last painting coat, but then you would still need to seal it with a fine art varnish to make it archival.

      4. Liquitex has a product called “Gloss medium & varnish”. A medium dries permanent, while a fine art varnish, as I just described, is removable. How they can label one product as both is beyond me. That product is a medium, and they are using the word varnish in a mis-leading way. If the product is removable and has UV protection (and these will be listed on the product’s label) then it is probably a fine art archival varnish. If it is not removable and has no UV protection it is just a medium. This can be used as a sealer but not as a final top coat.

      5. I’m not sure what you mean by varnishing mdf and birch ply. Are you asking what you can use to seal it prior to painting, or to varnish it over the painting? To seal prior to painting use any gloss acrylic medium. To varnish it over the painting you would need to use a fine art archival varnish as I mentioned above.

      Hope this helps answer your questions. They are good ones!


  36. Adrian Bangerter

    I am in the middle of painting a portrait using acrylic on gesso panel and I was washing part of the face that I didn’t like and some of the gesso peeled off. What’s the best way to repair it? Thanks

    • Nancy Reyner

      Hi Adrian, It sounds like your gesso did not adhere properly to the panel support. Or, the gesso is properly applied but you are using something too strong to remove the paint. If it’s the first reason – adhering issue – unfortunately there isn’t a way to readhere the gesso or fix it. However, I’d be glad to help make sure it doesn’t happen again. Please let me know which type of panel support you used. If it was pre-gessoed by the manufacturer, then this is not a brand you should use for acrylic. Ampersand is the only company I know of that uses the proper gesso to seal under acrylic, and with good adhesion. If you applied the gesso yourself, then perhaps you need to let it dry longer before overpainting it. Please add more details (type and brand of panel and gesso, what you used to remove the paint, how did it peel – small amount or more?) and I’ll be glad to offer my advice. Sorry about your issue. It must be frustrating as you are in the middle of painting.

    • Eileen

      I meant to say seal, rather than prime in my comment. Also, my husband says you can but a combined sealer/primer. Would that work?

  37. Jenny Arnold

    Dear Nancy

    Thank you for your very detailed and most informative descriptions.

    I want to make placemats; am using MDF wood, the biggest being 12×16 inches. I will probably put cork on the back. I want to do acrylic pours over the fronts.

    Does the same procedure you described also apply to thin 3mm thick MDF boards; namely seal, lightly sand, seal again to both sides and then apply 1 coat of primer eg Golden Gesso (is this the same as Golden GAC100?) to the front?

    If so, could you please suggest a good sealer obtainable in Australia?

    Also, as for a good gloss varnish, would a resin be the best which would give me heat protection for my placemats? For my canvases and vases, I suppose I could use a cheaper varnish which is UV protected. Is spray or paint on easier for beginners please?

    I know these are a lot of questions but you are obviously a wealth of knowledge and I hope you can answer them for me.

    Thank you so much

    • Nancy Reyner

      Dear Jenny, Sounds like a fun project! Yes you would follow the same procedure – sealing twice with a sealer (not a primer). I don’t know what is available in Australia for sealers – but any gloss acrylic will work to seal the raw wood. Please re-read the article to make sure you understand the difference between sealers (glossy – allows next coat to stay on top of this non-absorbent coating) and primers (matte – allows next coat to sink in to an absorbent coated surface). Since it is for placemats and not fine art paintings, I recommend you follow all the steps you mentioned, except once you are finished pouring, and the placemats are all complete, I suggest using a commercial product meant for kitchen counters – like a polyurethane for a final sealing coat over the whole project – paint, cork and MDF. Spray and paint options for varnishes are up to the user. I spray when there is heavy relief texture and/or the piece is small. I brush apply when the piece is large. Both application processes require some practice. There is no easy application (!) Hope this helps.

  38. Daniel P Gontar

    Thanks for the info. It is greatly appreciated.

    • Nancy Reyner

      You are welcome! Glad you like the article.

    • Emily

      Thank you for the informative article! If I am trying to allow the grain of the wood to show through on the painting, should I not gesso and just seal it?

    • Nancy Reyner

      Dear Emily,
      That is correct. Gesso is opaque and will cover the grain. There are products called “Clear Gesso” but that is misleading in my mind. Gessos add adhesion strength and are made with white pigment because these pigment particles add gripping power. Without pigment, it cannot be considered a real gesso. Instead it is merely a clear medium masquerading as a gesso. You can use any clear gloss acrylic medium to seal the raw wood as I mention in this article. Gesso is a secondary step (first step is to seal with a clear coat) meant to add adhesion between the wood and your first coat of paint. You can skip this step if you don’t want to cover the grain. When skipping this step, if you want to apply paint, as a suggestion use a thin layer of paint as your first paint layer instead of something thick like a paste or gel. This will help adhesion between your first paint layer and the wood.

  39. Amethyst

    Hi Nancy!

    Quick question: I bought a regular piece of smooth plywood stained it and applied a clear gesso and it isn’t drying clear. It kind of has a white dusty kind of look. I’ve tried multiple coats and sanding in between and I’m still getting the same thin white layer over the piece where you can also see some of the brush strokes. Is there a way to fix this?

    • Nancy Reyner

      Hi Amethyst,
      I highly recommend against using any type of “clear gesso”. Gesso is a white pigmented product that enhances adhesion. The pigment is an important ingredient for this purpose. A clear gesso means it has no pigment in it. So it is misleading in its name. A clear gesso is actually a semi-gloss or matte acrylic medium. Acrylic is naturally glossy. This means that any matte or satin or semi-gloss acrylic product has a white powder in it to give it some tooth. If you use “clear gesso”, or matte or satin acrylic mediums, you will get a translucent white film over whatever you apply it to. I believe companies that sell this are misleading the customer by repackaging a matte medium as “clear gesso”.

      As I describe in this article, there are two different steps to take when working with wood, each used for a different purpose and each requiring different products. First you seal (with something glossy). This is important to keep the wood from warping. The second step is optional. That second step is to prime with gesso which adds adhesion strength to the next layer applied to it, and also adds a white coat. It sounds like you are trying to seal and prime using one product and one application.

      Next time, use a gloss acrylic medium to seal. Then skip the priming step with gesso, and paint directly onto the glossy coated wood. If you want to add some tooth, lightly sand the glossy surface. You will make it slightly matte doing this, but there is no white powder added to this process, and therefore if you applied gloss over it again, the matte effect will disappear.

      Unfortunately the only way to fix what you have now, is to sand off all the way back to the wood and start over. Remember anytime you use a matte or satin product (which includes clear gesso) you will get a non-removable white film.

      Hope this helps!


  40. Julia

    Hi Would you recommend using “Gamblin’s Gamvar or Golden’s MSA Varnish (for brush applying) or their Archival Varnish (spray application)” on a fine art piece from 1944. Its a relief painting/sculpture … it has a couple of linear cracks. I’d like to protect the colors and protection from insect damage.

    • Nancy Reyner

      Dear Julia,
      Since the piece is from 1944, it probably uses oil paint. It is probably very dry at this point, if it hasn’t been restored since then, so adding a varnish would be a good idea for protection, avoiding any future cracking and reducing any color fading. Since it has relief texture, a spray varnish would be the best. Brush applications would work if the texture is slight. If the texture is raised quite a bit, then brush applying may create puddles in the crevices. Golden’s MSA Varnish comes in a spray (with a different name, though) called Archival Varnish. I recommend using only gloss, so the Archival Varnish Gloss will work very well. Matte varnishes contain a white powder that may not work well over the old painting. Another consideration is the back of the painting. Check it out to see if the canvas is OK. If not, you may want to apply an acrylic gloss medium over the canvas back to keep any moisture entering the painting through the back.

  41. Alex

    Hi Nancy

    Thank you so much for this detailed run-down! It is so helpful.

    I see you’ve got a lot of comments, I’d be here all day if I were to comb through each page – so apologies if my question has been asked before.
    I’m new to painting on wood panels and am very excited to go out and buy all the supplies I’ll need before I can get started.
    Forward thinking, is there a varnish or medium I should use or that you can recommend (specific to painting on wood panels) to finish & seal in my painting?

    Thanks and look forward to hearing back.


    • Alex

      Just to clarify, I’ll be painting on wood panels (birch) for fine art purposes that will be on display inside – not for furniture or outdoor use etc.

    • Nancy Reyner

      Hi Alex,
      I’m glad you are finding this article useful for your artwork. Once you prepare your panel following the instructions in this article, you can then paint on the wood. When you are finished painting you would need to apply a final topcoat of varnish. Fine art varnishes are different than hobby or commercial varnishes. Fine art varnishes have two important qualities. (1) They are REMOVABLE for cleaning purposes, and (2) they have UV protection so paint colors don’t fade. Golden has lots of great articles on their site. For starters here’s a good one:

      You haven’t told me what type of paint you will be using, and this makes a difference in the varnish product you will choose. If you are painting with acrylic, then you will need to do two steps over your finished painting. You need to apply what’s called an “isolation coat”. For this I recommend 1:1 Golden’s Soft Gel Gloss with filtered water. Over this you can then apply your varnish. I recommend Golden’s Polymer Varnish, which comes in a variety of sheens – gloss, matte and satin. Varnishing is tricky and I do recommend reading the articles prior to purchasing anything.

      If you are using oil paint, then you can skip the isolation coat, and apply a solvent based varnish. I like Gamblin’s Gamvar or Golden’s MSA Varnish (for brush applying) or their Archival Varnish (spray application).


  42. Tom

    Hi Nancy,

    I went out and got Golden’s GAC100 Acrylic Primer and Extender and did exactly like you said in your wood preparation instructions. I often extend drying periods between steps because I’m overly cautious and in no hurry. 1st coat went fine. Dried well. Sanding, cleaning, and all the usual steps went fine. Second coat seemed to go fine. The only doubt I have right now is that after about 5 days, the surface does not seem “kitchen counter” or “glass surface” dry. There seems to be a slight tackiness or rubbery feel to it when I press slightly with my the palm of my hand, or handle the panel with my hands. It’s very subtle but it’s there. I applied rather thin, normal coats, nothing too thick. In my 30+ years, my surfaces have always been bone dry before applying the gesso. This one seems to have a slight tackiness about it. Like I said, it very subtle, but I can feel it. Could this be normal for GAC100? Could this be because of the actual nature of the GAC100 product. The Golden website indicates that the GAC100 is “Useful for thinning or ‘extending’ colors as well as increasing ‘flexibility’.” I’m both curious and rather concerned because I don’t want to apply my gesso on a sealed surface that does not seem to be bone dry. I know it’s probably going to be difficult for you to make an assessment without being able to touch the panel surface in person, but maybe you can give me an answer from afar.

    Thanks for your time,


    • Nancy Reyner

      Hi Tom,
      That’s a very interesting question. I too have found the surface to be a bit tacky at times. It sounds like you did everything right, and after 5 days it should be bone dry as you said. In my experience I have found it varied in touch when dry. I do not think it is an issue that it has a slight tack, and applying gesso over it at this point should be fine. There are always variables with every process, so this means we will get variation in our results. Acrylic is so stable though that again I do not think it is an issue of concern. Acrylic will still continue to dry even if overpainted with other acrylic layers. The variables I found are: (1) Humidity and warm temperatures slow the drying and may keep the layer tacky for longer (2) The wood itself may have elements in it (either naturally occuring or in the processing of it) that react with the acrylic to keep it tacky longer (3) Different types of wood have different densities, and therefore some of the medium may sit on the top surface instead of sinking into the wood, causing the slight tackiness you feel (4) Make sure you mix the GAC100 well before applying. If it separates in the bottle and you only use the top part this could be an issue.

      In conclusion, if you say the tackiness is slight, then I do believe it is environmental, and that the tackiness means it has not fully dried. Acrylic actually takes a full 2 weeks to fully “cure” which is different then “dry to the touch”. Within this 2 week period it is fine to continue layering over acrylic layers. Once your painted wood is finished, before wrapping it or storing it, you want to wait a full 2 weeks for all the layers to fully “cure”. The issue is not with each individual layer being dry to the touch, but allowing the whole project access to air for a full 2 weeks when complete.

      Hope this helps!


    • Tom

      Hi Nancy,

      Some of the points you mentioned crossed my mind when I was questioning the whole thing. First of all, the GAC100 came in 8 fl. oz containers and were easy to rotate in my hand for easy mixing so the possibility of the contents being separated in the container was virtually impossible after mixing. Second, I thought I may have applied too thick a second coat, but I know I applied as thin a coat as possible. I think the answer is environmental. Montreal has been going through combinations of heat waves, up and down periods of humidity, etc. exactly the same time that I applied the sealer on my birch panels. Yesterday and today, with the humidity and heat subsiding, the surface seems a little dryer and harder than before. I know that the nature of acrylics when applied over certain thicknesses can be a little tacky/rubbery as it dries, so I assumed the GAC100, which is acrylic based, could present these dilemmas. I’m encouraged by the results in the last two days and I think you hit it on the nail when you said it could be environmental. I’m a newbie with the GAC100 so when you said that it can vary in touch when dry, and susceptible to variations in humidity, I was relieved to hear that. Like I said in my previous post, I’m patient and never in a hurry, usually preparing panels months before actually applying my first brush stroke, so I’ll let it cure for a while and go from there. Thank you for enlightening me on the subject.

      All the best,


  43. Michelle Roberts

    Hello Nancy, I want to paint on large wooden slabs an oil painting of my kids homes and then seal it and turn it into an end table. How would I go about it from the preparing the wood and to the sealing of it at the end?

    • Nancy Reyner

      Hi Michelle,
      Follow my instructions in this article for preparation of the wood. If you want to use it functionally as a table, I suggest your final top coat to be a commercial high grade product such as polyurethane. You want the top coat product to be durable, non-toxic once dry, and waterproof. Using a fine-art product for varnishing like I suggested would not work.

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Professional fine artist Nancy Reyner created this blog about art, painting and creativity from her career of over 30 years. She lives in Santa Fe, New Mexico. Subscribe below for free tips on art and painting.

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