Your finished work is only as good as the foundation on which it is created. It wouldn't do to create a masterful work of art or even a simple craft for pleasure or profit if done on a less than sure foundation; one which may allow your creation to lift, peel, separate or be scratched off the surface. In order to prepare a variety of surfaces I use Primocoat multi-surface primer. It is available in both white and black and adheres to wood, metal, glass, tile, canvas and most plastics. Here are some pointers on preparing a surface for painting.
Roclon all purpose cloth is a popular surface for creating banners and floorcloths. It has a fine texture weave that doesn't interfere with detailed painting the way a coarse canvas might. The only drawback is that it does have a linty surface which shows up in the painting. I have found that using Primocoat™ hardens the lint and allows me to sand it away using a fine sanding pad leaving a beautifully prepared surface ready for any type of medium. I wouldn't use Roclon without the base that Primocoat™ provides. Once primed, Roclon is a terrific surface that doesn't curl the way some canvas is apt to do. Because the canvas readily absorbs the primer, a single coat is adequate.
Preparing Glass, Metal, Plastic and Wood
Simply apply two coats of Primocoat™ to the clean, dry surface and let cure overnight. Primocoat™ can be applied to the entire surface or only under the area you wish to paint so that the glass remains transparent or the beauty of the wood grain remains visible. The primer can be lightly sanded if desired after it has cured.
"What makes Primocoat™ different or better?" you might ask. Primocoat™ is a resin based acrylic primer so it bonds with almost all surfaces. I have used it successfully on glazed porcelain, finished and raw wood, masonite, etched and plain glass, metalware, canvas and plastic. It is highly pigmented so that it provides excellent coverage. It is sandable and tintable and can be brushed, rolled or sponged onto the surface. Be sure to test it on a hidden area when priming plastic as there are many types of plastic and I have not tried them all. In the past I used a product called UnderCover™ but now use Primocoat™ exclusively.