Surface Preparation, Masonite

Surface Preparation of Masonite Panels.

A Brief History (Source: Wikipedia)
Masonite was invented in 1924 and has been used for many applications including doors, roofing, walls, desktops, and electric guitars. It is still sometimes used for house siding and, if kept painted at regular intervals, it will last the life of the house. Its popularity later faded, but it is still used, most notably by hobbyists.

It is formed using the Mason method, using wooden chips, blasting them into long fibers with steam and then forming them into boards. The boards are then pressed and heated to form the finished boards. No glue or other material is added. The long fibers give Masonite a high bending strength, tensile strength, density and stability. Unlike other composite wood panels produced using formaldehyde-based resins to bind fibers, Masonite is made using natural ingredients only, which makes it an environmentally friendly product.

Why Use Masonite
When properly prepared, Masonite provides a very stable, unyielding and tough ground for oil and acrylic painting. I have been using Masonite for the majority of my work from 1997 and only began using stretched canvas since 2007. Masonite panels can take some abuse and not tear like canvas. I have scratched the surface of three paintings over the years and was able to repaint and refinish all of these without much effort.

Raw Masonite does not like water and can be scratched with rough handling when transporting large sheets or working it through a table saw. Masonite comes in 4’ x 8’ sheets, and ¼ and 1/8 inch thick sheets. Most lumber yards will cut the sheets into more manageable sizes for a small fee.

One of the advantages of Masonite is the durable, tough, and unyielding surface it provides. I frequently use a single-edge razor blade held in a small plastic holder to scrape away some of the paint between applications. These holders can be purchased in the paint department of any hardware store for about a buck.

Just work carefully, and don’t put too much pressure on the plastic scraper on either edge, or it may gouge the surface too deeply. This works better than sandpaper and its easier (and safer) to control the pressure of the razor blade if it’s in the plastic holder. Hold the blade at a slight angle and scrape along the flow of the brushstrokes. This works best in areas with a lot of detail and results in a very smooth finish to continue building the layers of color and adding visual texture without a heavy build-up of paint. Sanding small areas between glazes creates some interesting results too.

Masonite Types
There are two types of Masonite that I am aware of. First, the “tempered” Masonite. It comes in 1/8 inch and ¼ inch thick sheets, 4’ x 8’ in size. The ¼ inch Masonite is quite heavy and larger works can be difficult to move around and hang. Tempered Masonite has a criss-cross pattern embossed on the back, and the front has a dark, slightly shiny surface. “Un-tempered” Masonite comes in 1/8 inch and ¼ inch thickness, and has a flat finish to the front surface. The back surface is smooth, and sometimes a little rougher than the front side.

I prefer the 1/8 thick Masonite. Smaller pieces of each thickness can sometimes be found in Home Depot or Lowe’s. I have used tempered Masonite for a few paintings, but either will work well for a painting surface. You can purchase various sizes of primed and mounted Masonite panels from most art supply houses. I haven’t tried these yet, but will soon.

How I Prepare Masonite
I am assuming that you have cut the Masonite into the sizes you need, or have purchased some already gessoed panels from an art supply house. The following steps will produce a lightly textured paint surface with tiny depressions and peaks that are great for thinly painted washes, scumbles or heavier, impasto painting styles. However, it will not have the weave pattern of a traditional canvas. All of this preparation sounds like a lot of work, but care taken here will provide a Masonite panel that is a pleasure to paint on and is the foundation of any successful painting. It is really time well spent. I usually prepare several panels (up to ten) at the same time.

While not really necessary, I lightly sand the unprimed face of the panel (the smoothest side) with 220 grit sandpaper, and vacuum all of the dust off. A coarse grit sandpaper or excessive sanding causes too much damage to the bare surface, and will be difficult to get a satisfactorily smooth surface to paint on. You can skip this sanding step if you want to.

I purchase Luquitex gesso in the one gallon size. This is very thick, so I transfer it to a one quart plastic bottle. Then I thin it with a little water (about 10%) and shake it well. I apply one coat of gesso using a 3 inch wide (Sureline brand) short-nap roller. These can be purchases at Lowe’s, Home Depot or Ace Hardware. They do come with foam rollers too, but I haven’t tried these yet. I prefer the textured finish the short nap roller produces. I let it dry thoroughly, and sand lightly with 120 grit sandpaper on a rubber sanding block. Vacuum the panel thoroughly and apply the first coat of gesso.

The first coat will not cover the raw brown surface completely and it will show through. Not to worry! If you hold the panel up to a strong light source and let the light shine across the gessoed panel at a low angle, it will not be smooth. You will see thousands of tiny peaks and valleys. This is exactly what we want. These valleys hold thin washes and the peaks can be sanded off and re-washed to give some surprisingly nice effects. It’s one of those happy accidents I found through trial and error. Lightly sand the first coat with 120 grit paper, and vacuum the dust off the panel.
Apply the second coat in a different direction with the roller, sandpaper lightly, and then apply a final third coat for best results. I always apply three coats of gesso to a panel, even if it came primed.

A few useful hints learned for applying gesso with the roller:

• Always use a short nap roller (I haven’t tried the foam type yet).
• I use a glass palette or plastic segmented food tray (see Tools and Equipment tab for photos) and squirt a good amount of gesso on the palette.
• I slightly dampen a new roller with the spray bottle of water/soap mix before working the paint into the roller.
• I work the paint into the roller thoroughly using a scrap piece of cardstock or Masonite.
• Be sure to use enough gesso on the roller and work it into the roller well. Otherwise, when you push the roller along the panel, it will skip and look like those newly painted lines on a highway where someone drove over it and left a repeating pattern of tire imprints.
• A new roller will leave some little clumps of lint from the roller during the initial coats. These can be picked or wiped off with a fingertip if caught right away, and won’t appear again as you use the roller on future panels.
• Apply the first coat of gesso to the panel, rolling in one direction.
• Don’t press the roller down too hard. If you do, will end up with long ridges of paint at the edges of each pass of the roller. It’s better to use a little more gesso on the roller than trying to stretch the gesso out too thinly.
• Work from one edge of the panel to the other, and overlap the strokes a bit.
• After three or four passes with the roller, run the roller lightly over these passes to eliminate any slight ridges and to even out the peaks.
• On a large panel, avoid going back over the first passes, as the gesso dries quickly and you could pull off some of the not-quite-dry gesso.
• When this coat is done, pick up the remaining gesso up with a palette knife and put it back in the bottle.
• Place the wet roller in a plastic sandwich bag, work all of the air out of it, and squeeze around the roller tube to remove all of the air in the bag. (The roller will stay wet in this for a week or more).
• Let the remaining gesso on the palette dry. Spray it with the water/soap mix, and it will scrape off very easy with the single-edge razor blade.
• Let the panel dry thoroughly (more than one hour) before lightly sanding the panel and applying the next coat.
• Don’t stack or lean the panels face side to backside on another panel for a couple of days or more, or they will stick together.
• Put three coats on the face of the panel.
• I also apply at least two coats of gesso to the back of the panel. This helps prevent warping of the panel when painting wet on wet. Don’t bother sanding the back or fussing too much with it.
• I hit the edges of the panel with an almost dry roller between coats. If the roller is to wet, the gesso will squish over the face and back of the panel.

Scumble
About the word “scumble”: This is the action I use of quickly scrubbing thinned acrylic paint, in a random motion, partly covering the previous layer of paint. You want some of the previous layer to show through each time you lay down a scumble.

The brush action goes every which way in doing this without completely covering the previous layer(s) of paint. It’s done quickly and lightly, and produces a good effect on Masonite panels or canvas. The viewer’s eye will naturally mix the colors in their brain. This method of preparation enhances a scumble, wash or dry brushing and will produce some surprising and pleasing results in your work.

If You Want a Very Smooth Finish on Which to Paint:
I often like to work on a very smooth panel without all of the peaks and valleys the previous method produces. An ultra smooth surface with enough gesso on it works very well with glazes, multiple washes and scumbles. I prefer this type of surface to paint in thinly applied washes. I always sandpaper or scrape successive applications of paint between coats to retain the smooth surface.

Tools
I use the glass pallet, a 7 inch pallet knife, a flexible plastic ruler, a small round tip pallet knife as shown in the photo below.

To get this smooth surface, I use all of the methods above. However, after the second coat of gesso has been applied and thoroughly dries, I sandpaper it a little more smoother using my fingertips and a strip of sandpaper folded three times. I sand in a circular motion all over the panel, checking it frequently by holding it up at an angle to a strong light source (my quartz desk lamp is perfect for this.) This helps me to spot any imperfections or ridges from the roller.

The Process
I lightly mist the surface with the soap/water mix, then quickly wipe almost dry with a paper towel. I apply the third coat of gesso to the panel using the large (7”) palette knife to quickly spread the gesso over the entire panel. I scoop up the gesso and spread it over the panel holding the 7 inch knife at about a 45 degree angle. I work from the middle of the panel to the edges, rotating the panel 90 degrees and working it all to the edges.

Next, I immediately spread this smooth using a thin, flexible ruler that came with a “Day Timer” calendar refill working from mid-panel to the edges. It’s a bit tricky to get the angle and fingertip position just right on the flexible ruler, but once I did, it went quickly and came out much better than the using the large palette knife. I use the small pallet knife to scoop up remaining gesso on the pallet and put it back in the bottle.

The first coat of gesso you spread over the rolled surface with the palette knife and flexible ruler will leave a series of tiny, parallel ridges. When thoroughly dry, sandpaper the ridges, again using your fingertips and sanding in a circular motion. Check the surface with the light source and sand out any small ridges remaining.

I apply a second coat of gesso, spreading it with the large palette knife in a slightly different angle than the first coat and use the flexible ruler to smooth out the surface. When thoroughly dry, sandpaper the ridges, again using your fingertips and sanding in a circular motion. Check the surface with a light source, and sand out any small ridges remaining. By now, the tiny, parallel ridges will be fewer after sanding. I usually end up doing this last step in three coats of gesso on top of the rolled surface. You end up with a velvety smooth surface with enough tooth and fine, almost microscopic pits that work great with thinly applied washes and scumbles.

This is a lot of work, but this effort produces a wonderful surface that is a pleasure to paint on. If you’re taking the time to put the effort into the painting, start with a good preparation of the panel (or canvas) that can only enhance your painting experience and pleasure.

As always, your comments and suggestions are welcome.

Don