Cotton duck canvas is much less expensive than linen and has become the most popular support for oil and acrylic painting, especially for students. A properly prepared cotton canvas has longevity similar to linen, and it's more flexible and easier to stretch properly. However, cotton duck is considered too flexible for very large paintings.
Linen canvas with an oil primer is the classic standard for oil paintings. Though more expensive and harder to stretch properly, linen canvas offers the smoothest and stiffest painting surface and has proven longevity. Strong and durable, linen holds up to a heavy painting hand and doesn't become slack as easily as cotton canvas. For many artists, linen canvas is worth the investment.
There are three standard methods: side stapling, back stapling, and spline finishing.
Side Stapling is the least expensive technique for securing the canvas to the stretcher bar because it uses less canvas. Finished pieces are generally framed to hide the staples.
Back stapling is a more expensive finishing technique and requires more canvas, but it provides more selvage for future restretching. Some artists paint on the side as well as the face, creating works that don't require framing.
Spline finishing is the most expensive finishing technique. Though some artists feel that it's not as easy to restretch a splined canvas as it is a back-stapled canvas, many artists choose splined canvas because it has a neater appearance than other finishes, and because it's popular with their customers. Splined canvas hangs tight to the wall.
Depending on the canvas, you may opt to hang your work without a frame. If you do choose to frame your canvas painting, canvas frames and open back frames are commonly used for stretched canvas or panels. These frames are meant to hang on the wall and don't have any glass or glazing material covering the work. Another option is a floating frame for canvas, which creates the illusion that your artwork is "floating" within the frame.
When stretching your own large canvas, you may choose to add cross braces to your frame for extra stability. For the correct fit, order the cross brace in the same size as the stretcher bar to which it is parallel. The actual measurement of the cross brace will be shorter, but it will be sized to fit inside the assembled frame.