Heavy Textures For Artwork

I frequently use Plaster of Paris as a medium for creating texture or for embedding or coating applied textures. I've covered this topic in the first lens of this series, but a review is called for here, as well.

It's up to you to experiment with the consistency of the plaster. There's a fairly narrow window between being too stiff and too runny, and different consistencies allow for different textures. For making peaks or deep valleys, so to speak, you'll simply need to mix the plaster up thicker.

Once plaster has cured, you can't re-wet and re-work it, so it's kind of a one-shot deal. You just can't treat it like clay, which can be re-worked indefinitely. But take heart: if things don't work out the way you'd envisioned, all is not lost. You can carve and scratch and scape and sand, which are all ways to achieve textures in and of themselves. Or you can sand the cured, dried plaster off completely and start over.

WORKING WITH THE PLASTER:

For mixing plaster, I like to use a large, plastic yogurt container. It's flexible, and once the residual plaster cures, the cup can be "massaged" and all the plaster will break out, making it possible to re-use the cup. Other containers, such as metal coffee cans, would not be conducive to multiple uses unless you wash them out before the plaster cures.

Once your plaster is mixed, you only have somewhere between five and fifteen minutes to work it before it starts to cure. Depends on the mix, the type of plaster, room temperature ... lots of variables. What it boils down to is you need to paint or rub it on quickly and have a plan.

While plaster cures in a matter of minutes, that doesn't mean it's dry. In order for any primer coat of paint to properly adhere to the plaster, the water must evaporate off so that the plaster becomes porous enough for the paint to soak in and "bite."

I generally lay out my plastered paint boxes on newsprint and let them dry overnight. Never place the freshly plastered canvas on a cloth or towel, as they will likely stick, and it will be difficult to get the canvas off and the plaster out.

And just a word from the wise (who've been there, done that): Don't wash uncured plaster down the sink. It will set up in the p-trap and ruin the drain. Instead, scrape out residual plaster and throw it away, or wash your container in a bucket and dump it outside.

If you're just using plaster, you won't necessarily need to use any adhesives, but if you're stickin' things to the canvas to paint on, here are a few tips.

First, here are some products I've used for attaching applied textures to my wooden canvasses:

• white glue (ie. Elmer's)
  
• wood glue
  
• epoxy
  
• contact cement
  
• construction adhesive (ie. Liquid Nails)
  
• silicone RTV ("room temperature vulcanizing")
  
• hot glue

Through trial and error, successes and occasional serious failures (sorry, wife, about that splotch on the carpet), I've learned that some of these products work a lot better than others, and each has its pros and cons.

White glue: a good all-purpose glue. It's water-soluble, so no harsh chemicals are needed for clean-up. White glue is great for applying paper and decent for attaching wooden objects. It does take a while to dry, so objects have to be secured in place until the glue sets up.

Wood glue: a better choice than white glue if attaching pieces of wood (or wooden objects to a wood canvas). It tends to be a lot stronger than white glue but has similar drying characteristics. Also like white glue, wood glue requires just water clean-up. Both wood glue and white glue polymerize during the drying process, so they become insoluble once dry.

Epoxy: super strong and available in different cure lengths, varying from five minutes to 24 hours. Epoxy requires mixing a resin with a hardener, and the proportions must be correct or you end up with a glob of goo that will not cure. What I do like about epoxy is that it's transparent and flows easily into holes and cracks to fill them up. On the other hand, epoxy can be difficult to clean up. About the only thing that will get at it is acetone.

Contact cement: dries quickly and makes a strong bond but is fumey. This is great for attaching pliable materials to the canvas, such as leather or textiles. It allows for flexure and will not crack. But, boy, is it ever stinky and clean-up requires harsh solvents.

Construction adhesive (ie. Liquid Nails): I know a guy who glues large pieces of flagstone to a plywood backing and trusts the strength of construction adhesive to do the job. He hangs these mounted rocks on the wall just as you would a picture. On occasion, I use this product to glue ceramics and other heavier materials to a wooden backing, but, again, this is a very fumey product. Use good ventilation.

Silicone RTV ("room temperature vulcanizing"): I'm going to do a complete, separate lens on some cool things you can do with silicone, so stayed tuned. Watch out for using silicone in a painting, however, because paint will not stick to it. Silicone tends to smell like vinegar while it's curing. Before it is cured, it can be cleaned up with mineral spirits. I've had success attaching glass to other materials--glass to wood, glass to ... whatever--using silicone. It also is good for attaching styrofoam as it does not attack the foam. The stuff you get at the hardware store requires moisture (from the air) in order to cure.

Hot glue: This is just the ticket when you need to stick somethin' dang near instantly, like when I glue rope to a wooden canvas. Hot glue is gooey and sticky when hot, and as soon as it cools down it hardens; however, you do need a hot glue gun in order to apply it. Hot glue is not quite as fumey as other adhesives I've mentioned--I'd say it smells a little like pine, actually--and I'm unfamiliar with any clean-up methods. Hot glue tends to repel paint, as does silicone.

Along with adhesives, I sometimes use mechanical fasteners to attach objects to a wooden canvas and here are my favorites:

• drywall screws
  
• wire nails
  
• finish nails
  
• staples
  
• baling (or bind) wire

We already talked about the basics of using plaster. So what do you do with it? Well, take out your appendages--I prefer fingers to toes, but just about any body part will do as long as you don't cure the hair still on your head to the canvas--and have at it.

Pretend that you're back in gradeschool, and the teacher put the finger paints out. Just pour a puddle of freshly-mixed plaster onto your canvas and swish it around to make interesting designs. You will get a feel for how quickly the plaster sets up, so have some sort of plan in mind before you mix and pour.

You can work the plaster clear on up to when it cures, but don't add any more water once you've started working it. That will ruin the cure.

Now set the whole thing aside, let it dry completely and you're ready to begin painting. You can use any type of paint on the plaster surface, keeping in mind that it is very porous, so a good primer, such as artist gesso, would be prudent.


(Just a note: The photo with the wet plaster does not end up as the photo above. The wet plaster you see would have been too thin to produce the prominent texture on the dried canvas I'm holding.)

Okay. So, you're frantically modelling your quickly setting plaster, and you don't like what your fingers are doing for you. So why not grab an implement--from a kitchen drawer perhaps--to take the place of your digits. The first that comes to mind is a good ol' fork. You can scratch some terrific lines into the soft plaster with hard tools like the following:

• fork
  
• spork
  
• saw blade
  
• spring (aka coil)
  
• coarse wire brush
  
• comb
  
• gears and sprockets
  
• cheese grater (just don't tell your wife)
  
• wooden dowel, pencil or handle
  
• meat tenderizer

Just as with the hard tools above, there are endless possibilities to obtain textures with soft "tools" as well. Scratch, squeeze, roll, smear, brush your way to success. Here are some ideas to get you started:

• sponge
  
• soft bristle brush
  
• carpet
  
• textiles
  
• feather
  
• crumpled paper
  
• sheet plastic
  
• bubble wrap
  
• rubber (ie. a piece of tire tread)
  
• boot sole

Along the lines of using a tool to scratch, abrade or smear, it's possible to get a great texture by pressing an object into the fresh plaster and then removing it. Organic materials make for some really nice impressions, but you can of course use inorganic "tools" in the same way. Here are some ideas:

• leaves
  
• sticks
  
• twigs
  
• pine needles
  
• feathers
  
• bones
  
• bark pieces
  
• stones and pebbles
  
• flowers (fresh or dried)
  
• food (ie pasta, vegetables)

There are two ways that I do embedded texturing. The first method is a bit more difficult and requires more tools, and that is to mix the objects (and, in this case, they have to be hard objects) in with the plaster in the pour. After the plaster has completely cured and dried, the plaster covering the objects is removed with sandpaper, scratching tools or a sand blaster. A sand blaster actually works really well.

The second method is to pour the plaster, then place the objects into the wet plaster and allow it to cure and dry.

The advantage of the first method is that you get a good contact with the plaster and good adhesion of the object/s. The voids behind the objects are also completely filled. However, removing plaster is not an easy task unless you do have access to a sand blaster.

The advantage of the second method is that you get a chance to place the objects wherever you'd like, and you don't have to scrape away any residual plaster. On the other hand, you will tend to have voids or air pockets that might be frustrating when you start to paint, and occasionally an object may dislodge, requiring an adhesive to reattach it.

Make sure you are protected against free silica exposure by wearing the proper face mask and covering your skin if using a sand blaster.

Here are examples of hard objects one can embed:

• nuts and bolts
  
• old keys
  
• buttons
  
• marbles
  
• rivets
  
• nails
  
• stones
  
• broken glass
  
• screen
  
• bones
  
• hair accessories or "bobbles"
  
• costume jewelry

This basically means gluing, screwing or attaching objects by some means--mechanical or otherwise--to your backing. Lately, I have been using a hot glue gun to attach rope to my wooden painting boxes.

The sky is the limit on this one as long as the objects are paintable if that's your intent. There is some trial and error involved here, as some objects stick better to certain adhesives than others, and some objects require mechanical attachment.

In the following pictures, I'm hot gluing the rope directly to the wood (luan) and, afterward, using a propane torch to burn off the fuzz. I then primed the wood and the rope assemblage with Gesso, ready for paint.

Here is an example of applied texture (rope) on a small wooden painting box, primed with gesso and painted with acrylic. I then coated the piece with polycrylic.

It's a little hard to see the texture in this work, but it is an example of glued, screwed and painted cardboard, papercrete, and plywood. This piece was approximately 3 feet wide and was part of the 2007 Recycled Art Exhibition here in Flagstaff. To my pleasant surprise, the piece sold before the show even opened to the public.

This is a close-up of one of my 2009 entries into the Recycled Art Exhibition. This piece utilizes applied textures including plywood, scrap metal and thick house paint.