Do you size Masonite?
 

I've been using Masonite panels for awhile now, especially for quick stuff and the not-so-important. I've always used the smooth side, which I rough up with course sandpaper, and then apply gesso. It usually take two -- sometimes, three -- coats to get it sifficiently isolated from the fiber panel.

I recently decided to try using the rough, dimpled side of the Masonite panel, and was surprised at how much gesso this side of the panel drinks, and continues to drink.

I got to wondering if it would be wise to size the rough side before putting on the gesso. I used to keep some animal glue, but lost it, or threw it out several years ago. Don't want to buy a big batch for a small experiment. I'm not sure I'll want to paint on the rough side, anyway.

I was wondering if something like dilute Elmer's Glue would work as a size for the rough side of Masonite.

Any ideas?

I must admit masonite makes me nervous, but I still use it occasionally as well. I'm surprised that sanding the masonite first doesn't cause you more problems. I had someone help me cut a bunch of little boards from an 4' by 8' tempered sheet from the lumber yard once. The saw blade we used was not fine enough or something, and we ripped up some of the edges. I just sanded those down a little, and they looked fine...until I gessoed them. Then these brown stains leaked up through the gesso everywhere I'd had a rough edge. Multiple coats did not help.

When I gesso, I never sand the masonite. I just use a paint roller or sometimes a really fine sponge to apply gesso. That usually provides plenty of texture for me. I still have to apply two or three coats to really cover up the dark surface.

Jen:

Those pesky brown stains may have come from the tempered masonite. As I understand it, there is UNtempered masonite, and tempered masonite. I read that the difference was that tempered masonite was made with oil and a lot of heat, the reason being that it was for use out of doors. The untempered masonite, the article said, was made without the oil, and was for use indoors where the elements (rain, snow, I suppose) would not affect it.

Later, I learned from my son, a carpenter, that the difference is not oil, but this: tempered masonite is made with extra water and a lot of heat and pressure. Untempered is made with water, also, but no heat or so much pressure.

Now that I've really confused the issue, I can't tell you which is correct, either.

But, if you used tempered, which, supposedly, is made with more water and heat, those stains could be from leaching out some of that stuff that was"made" from the heat and water. Whew! Who knows.

I have never had this brown stain problem with my untempered masonite. However, where I do get leaching is if I use a felt tipped pen to mark the masonite, and if I forget and use it on the side I'm going to paint. When I start the gesso, it continues to leach up through the layers of masonite.

Unless someone can tell me more, I'm going to go back to using the smooth side because it seems to be sealed tighter. The rough side acts like a sponge. Even after three or so coats of gesso, and fairly thick ones, too, it still sucks up the new layers of gesso.

By the way, you can make some interesting textures on your masonite panely bu applying the gesso with various things like a small whisk broom, or a wallpaper paste brush.

I don't post here much (more to read than I can cover) but anyway....

First, I think they don't make Masonite any more--that's a brand name--but there are several companies that make compressed hardboard that is similar to it. Unfortunately, there seems to be a very wide variation in how hard the hardboard actually is.

Next, it's not clear to me if you're using traditional gesso or acrylic primer that's sold under that name. My guess is you're using the acrylic stuff. Real gesso is made with whiting and glue (traditionally rabbit skin glue or today sometimes other kinds) and is often made by mixing various proportions of the powdered ingredients in water. Acrylic "gesso" is dilutable in water, too, of course, and in my experience, the water soaks into the hardboard and will bring up the brown stains you've seen. On the other hand, real gesso hasn't done that for me, probably because of the glue. Some experts recommend that you give the panel a drink of diluted glue solution before applying traditional gesso. I'd guess that's why traditional gesso doesn't bring up the brown stains.

Sanding the smooth side of the hardboard is actually a good idea when priming it because it increases the mechanical bonding of the primer to the wood--I use 120 grit paper. It doesn't require a great deal of sanding, btw--barely enough to rough up the surface. You don't have to do it, but when using traditional gesso, sanding is a good idea. Most who prepare their own gessoed panels sand between coats as well, and may apply as many as six coats (usually at least three).

I don't know if this is helpful or not, so if not, then "never mind."

Oh, and if you don't want to go to the trouble of doing it yourself, you can get some lovely prepared panels from http://www.realgesso.com/

Thanks, Gary! Nobody ever explained the difference between real gesso and the acrylic primer. Of course, I've had a salesman at a supply store strongly recommend Golden's over the cheaper generic brand, but he failed to tell me exactly why it was so much better...and more expensive. Perhaps he didn't really know himself.

And you're right about Masonite. It's simply called hardboard now. I called three lumber yards, none of them carried "Masonite." But at least one customer service guy knew what I needed!

You're very welcome.

Yes I'm afraid that a great many art store employees know more about how to run the cash register than they do about the materials they sell. If you'd like to try traditional gesso, you can order some pretty inexpensively from Studio Products at www.studioproducts.com

Gary:

Sorry . . . I use "gesso" without defining which one. I use the acrylic version since it is easier (IMHO) to deal with. Little or now mixing, etc.

In my recent "trail," I've been using straight out of the tub, thick and gooey, and that infernal hardboard (the rough side) just keeps slurping it down. Not going to do that anymore.

I have used the Acrylic Gesso for some canvases. After sizeing with Animal glue (bone ) 2 times and a light sanding I gessoed 2 times. When I use such a canvas I like to oil it over from the start.

You can use Animal Skin Glue, Acrylic binder or even Linseed Oil with White spirit if you let it dry well before gessoing on Masonite. I never use the rough side.

The Acrylic Gesso is best for canvas because of the flexibility of Acrylic binder. If you prefer traditional Gesso be sure to make it an Oil, Egg and Glue Gesso.

Allan

That is an excellent idea! I find that gesso on any board is quite thirsty. Oiling out before painting is a fantastic solution to that problem.

On another note, I like to use MDF instead of masonite (hardboard). You won't have the problem with those fine fibers on the sides (where the board was cut) soaking up moisture. That problem is much like getting window cleaner under a glass tabletop. It's impossible to eliminate. With MDF, the composite is consistent throughout and fairly stable. It weighs a bit more but is available in 1/4" thickness which isn't too bad.

I know that doesn't exactly fit the original question but it's a thought to consider.

A while ago, I had a long talk with Micheal Harding the English paint maker. He said MDF board was the most stable paint surface available. It really does not need any sizing, just paint on it. I use it for my large pastels. Just give it a light sanding to make the paint adhere better.

No gesso, no nothing. Simple and archival.