At this stage in our presentations in the shop everyone has glazed eyes and is already somewhat confused by all the paint options so I give them a photocopy of a club sandwich of sorts we invented when doing the very first demo in my shop (probably to be a bit clearer about the whole thing ourselves!). Here it is…
Basically in this section we will concentrate on the three at the bottom. The first one has no impact on your painting proper, it’s just there because without it there would be no second one! Then we enter supports, not the subject of this page but still, these will have a definitive influence on what you need to do next. Most surfaces that you will choose to paint on will need some some of prep… Which is why you should you care about size and gesso. A well prepared surface will give you enough absorption to allow your paint to adhere to your material and, also, by playing with your gesso you can get your surface ready for the kind of work you have in mind… read on… lots of fun options ahead (and we’re not even talking mixed media!)
Fabric supports such as canvas -whether linen, cotton, polycotton, polyester- are probably the most common and there is a fair chance you will, at some stage, buy a stretched canvas or canvas on the roll, that is already primed with gesso…. most probably it will have been triple primed with acrylic gesso (its proper name is not gesso at all by the way but “Acrylic Dispersion Ground” but don’t worry nobody knows or names it like that). If you are happy with the feel of it and know it’s a good quality one you can go ahead and skip this whole section, jump on your paints and go for it! If you are unsure of your primed canvas quality and/or wanted to add one last layer of gesso for good measure while meditating on what you will paint there, do so, it won’t do any harm and, if nothing else, it will save you some paint as poorly primed canvases seem to simply drink the stuff (another reason for buying at least OK quality).
Many artists painting in oils still size then prime raw canvas themselves and rather enjoy that procedure. Years ago it was standard practice at art school to stretch and prepare your canvases and so quite a few still want to do it the traditional way, applying the recipes probably learnt there or taking the short cut to a ready made oil primer on top of their rabbit skin or other hide glue. This is not the way to ground your support for your acrylic paints and, although still sold, it seems that actually animal glues+oil primers are in fact not such a good idea at all… even if you paint in oils… go here for a read if you have an interest.
So, whichever of the following gessos you choose, if you paint in acrylics or any other waterborne paint, prep your support with an acrylic size + acrylic primer (most are). There’s hardly any sense in painting the other side of your canvas is there? Sizing a raw canvas -or any other fabric for that matter- will create a first layer/barrier and is best done by applying one/two coats of Golden’s GAC 100 or a polymer medium such as Matte Medium or Fluid Matte Medium. GAC 200 is also an option if you want more rigidity but must be applied when the temperature is at least 70°F / 21°C. But sizing is not enough. Yes it does what it is meant to do, ie making sure all fibers and threads are sort of pushed back and under control and won’t stick out in your painting later but sizing alone does not provide you with a true ground to paint on. So you now need to put a coat of gesso, then another, then another with light sanding in between each coat (even more coats if you want a less flexible fabric.)
The most common gesso is white from the Titanium white pigment in it but you can use a transparent gesso (or fluid mat medium) if you wanted to keep some of your surface visible. You see more and more raw linen stretched canvas primed in transparent gesso and artists can achieve some lovely effects on these. You can also use a sandable hard gesso in order to smooth it down afterwards or add more tooth by using a gritty primer like Colourfix or any pastel primer. You can use an absorbent ground to increase the natural absorbency of the canvas making it more like paper… great for washes and watercolour effects. You could also use ready-made coloured gesso as a sort of under-under coat or add some colour to your gesso (some artists just paint their pre-primed canvas… white!)
Wooden supports such as painting panels actually do not differ much from sizing + priming raw canvas. You want to first make sure you create a barrier between your gesso/paint and your wood to prevent the terrrrible SID (surface induced discoloration). When your paints dry, they retract and to hold on to the surface they actually pump up that surface… in the case of wood that process can also bring up some of the wood tannin, a problem especially for your lighter colours. GAC 100 does the trick, others will use PVA glue… I leave that one up to you. After it’s dried you can layer your coats of white, transparent or colour gesso onto your wooden support.
Paper/cardboard is of course something you might wish to draw on but also add paint to. There are some ready made “acrylic” or “canvas” paper on which you can jump, also all manners of “mixed-media” paper which will take a fair bit of paint before protesting (ie buckling). All these come in rather smallish sizes so if you want to go bigger (or cheaper perhaps) start with a good quality heavy paper 150+gsm and… on with the gesso. One, two, three coats… a bit of sanding between them, and hey presto your paper is much less absorbent, less flexible and much happier with paint on it. (To prevent bowing of your paper -acrylic paint is after all full of water- you might wish to also size/gesso the back.) You can increase the tooth to help adhesion of pastels, charcoal, pencils by using a gritty primer like Colourfix or any pastel primer. We are still talking fairly lean paint layers here as the weight of impasto paint would probably not be held by paper. AND we are still talking paper here so you will have to frame your artwork at the end in order to protect… the other side! But you know what? It allows you to play at lesser expense… if the result is worth it you frame, if not, in the bin or the folder it goes. Paper is cheaper but more than anything, if you ask me, it is a much much nicer surface than canvas… my taste tis all.
After that you enter the world of “other surfaces”: walls, dibond, plastic, glass, porcelaine, leather, bone, stone… you name it, I think I’ve been asked if and how you can paint on it. Answers will differ too much from situation to situation to go into detail here. It also all depends if it’s for fun or if you intend selling that piece later and thus have conservation in mind. If you are keen for that, scout the Just Paint website and you might find your answers or send an email to the technical support team at Golden they are simply Amazing!
A little addendum about Digital grounds… These are available to prepare your paper (or virtually anything you can get through your printer) to receive the ink-jet inks and better preserve your print from fading. A print you might never even paint on, it might be your finished piece… or you might collage/fuse it into a piece. So although it has the same name and use as “ground” it might not quite sit in the same place in the art sandwich.