Saturday, January 26, 2013

Preparing Painting Panels

(transferred from original post - May 2010)


After experimenting with various woods, thicknesses, supports and grounds, and after extensive research online, books and articles. I believe that I've found a relatively fast, reliable method of preparing high quality wooden panels.

Wood

I generally paint on a small scale (16” x 20” maximum) and I've found that building and attaching supports to keep thinner substrates from warping is a step that can be avoided by using thicker high-grade plywood. Although 3/8 inch ply should suffice for sizes under 16 x 20 inches, I prefer to minimize any chances of warping by using ½ inch grade B (or BB) Baltic Birch. There are many types of hardwood ply types and depending on your desired results and application, most will work, but I find the fine grain and overall smooth texture of Baltic Birch ply provides an excellent foundation for a smooth finished panel.
Take care when buying plywood that it is made of one-piece layers stacked horizontal/vertical or so that the grain of each layer runs perpendicular to each succeeding layer. This type of plywood manufacturing is known for it’s exceptional strength and resiliency against warping and bowing.

Materials Needed:
Gesso Types:


There are a lot of artists who will devote hours of painstaking labor into making their materials in the tradition of the old masters or because hand made materials are generally of higher quality (which is why I prepare my own painting surfaces). Store bought panels can have less than desirable finish flaws, warp and even crack. But when it comes to gesso, I feel comfortable in leaving it to the professional manufacturers and I've never had any problems with any over the counter gesso products.


Since the science of painting sometimes brings out the scientist in us, it’s all too easy to get wrapped up in experimenting and making artist’s materials, leaving us with little time to paint. In a perfect world we’d have assistants to grind and mix pigments and prepare panels but these days we have to pick our handmade vs. store-bought battles.


The Process:
  1. Cut plywood to size and sand with 200 grit sand paper. Lightly round off the corners and hard edges that can keep the gesso from bonding all the way around the board. Slight scratches, divots and irregularities will eventually be covered with gesso, but you’ll want to sand away any protrusions.
  2. Before applying gesso wipe off any excess dust with a towel and remove residual oils by gently cleaning all sides of the panel with a clean towel and rubbing alcohol. You are now ready to start applying the gesso.
  3. With a soft square brush, my favorite being a 1” Loew-Cornell 1177 Brown Nylon (also great for varnishing), brush on a thin coat of regular acrylic gesso in a horizontal direction to the face. Work the gesso in to the surface and sides and lightly level out the brush strokes. Let it dry for approximately 2 hours.
  4. Once the top and sides have dried thoroughly enough that you feel comfortable flipping it over, lay down a sheet of wax paper and repeat step 2 on the backside of the panel. Be careful to keep the gesso from running onto the face. Let dry for another 2 hours. This coating that will create a strong bond all the way around the panel and will provide a counter layer that will reduce warping and yield a more aesthetically pleasing finished panel. No additional gesso coats are necessary for the back and sides but you can apply them if desired. Let dry for 4 hours.
  5. Once the face is completely dry. Lightly sand all sides with 200 grit sand paper focusing on sanding down high spots and very slightly rounding the edges.
  6. Wipe away dust with a dry towel and apply gesso perpendicular to the first coat. Sand let dry for about 6 hours and repeat this step always apply perpendicular to the previous layer until you have completed 5 coats.
  7. Sand the final regular gesso coat and apply Golden (brand) Sandable Hard Gesso in the same fashion, sanding between coats until you’ve applied at least 3 coats. The Sandable Hard Gesso is excellent for achieving an ivory finish in about half the sanding time. Let completely dry for at least 8 hours.  (You can achive the same finish with only using regualar Gesso for the final coats and omitting the Sandable Hard Gesso)
  8. After the final coat is dry sand with 200 grit sand paper until you have reach your desired surface texture. Personally I like a perfectly smooth ivory-like finish so that the tooth of the panel doesn't detract from the realism effect. Wipe away dust - you are now ready to paint!!!

2 comments:

  1. (transferred from original post - Jan. 2012)

    I am switching to baltic birch and want you rec. for pieces that are 5 ft x 5 ft. Would 1/2 ” prevent warping? What to do to the back for support hanging?

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    Replies
    1. (transferred from original post - Jan. 2012)

      Hello Christine,

      Because larger sizes are more prone to warping when exposed to moister, temperature and/or humidity changes, I would consider using marine grade ‘Okume Mahogany’ instead of birch. If you plan to make the panels yourself, you’ll need to make sure that they’re properly braced. Check out the John Annesley Company, they sell custom supports and they have some good information about supports and bracing on their website – http://www.johnannesley.com/CradledPanels.html

      As far as hanging your panel, I’d suggest using heavy duty strap hangers “without wire”. Strap hangers are commonly used to hang big/heavy objects like mirrors or oversize pictures and your local picture framer or hardware store should have them. – http://govart.com/hardware_hangers_hvy_A.html

      I Hope this helps! If you have any other questions – please feel free to ask.

      Best,
      Slade

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