A canvas stretcher is someone who professionally creates stretched canvases, these are also sometimes called boxed canvases.

Canvas stretching services are commonly used by artists who want custom canvas sizes,as well as to save time and get a professional result.

In general, professional artists will not use machine made stretched canvases as they are considered low in quality. 

Canvas Stretcher - Job Description:
Canvas stretching is a skill that anyone can learn to do at home see: How to stretch a canvas.

Basically though you use framing and carpentry skills to construct a custom sized backing frame, or piece together commercially manufactured pre-cut stretcher bars. Stretcher bars come in set lengths that are either timber stretcher bars or aluminum stretcher bars that lock together. The artists canvas is then stretched over this.

There are many types of artists canvas used that have various qualities. The most popular is called Cotton Duck, the highest quality artists canvas is Linen of various weights. You may need to advise a client on the best choice for their type of painting technique, or offer them a cheaper alternative whilst being able to explain the differences in the types of canvas, their quality or longevity.

A canvas stretcher may also be required to 'prime' a canvas, by sealing it with gesso. This is commonly done in a spray booth. A spray gun and air compressor is used to apply coats of gesso to the stretched canvas which results in a very smooth even finish, this gives the surface a 'tooth' to which paint will adhere to easily but will not soak through to the canvas.

A canvas stretcher may also need to know the range of backing frame supports available and how they can or can't be used with some moldings used when framing the canvas. You see, some slender stretcher bars and therefore thin stretched canvases may not be able to be properly mounted in some types of frame moldings. So knowing if the stretched canvas is likely to be framed or not, can sometimes be helpful

To pursue a career as a canvas stretcher it helps to have an interest in fine art, framing and carpentry.

Canvas Stretcher - Employment Start:
Canvas stretchers usually work for an art supply store, a framing supplies store, a framing service, or a specific canvas stretching company. You may be hard to find a canvas stretching job advertised. You could enquire with businesses of this type in your area and perhaps ask for work experience.

the best employment start would be to work with someone else, to gain the knowledge and skills, and then perhaps you could consider starting your own canvas framing service, and sub-contracting work where your local art supplies store receives orders on your behalf and invoices the client too. This way you have access to a steady number of jobs and have less business running responsibilities.

Canvas Stretcher - Training & Education:
The best way to learn, is just to do it, see: How to stretch a canvas and practice.

There are not many courses offered specifically for canvas stretching. Some art colleges do provide students with canvas stretching classes to teach them how to do this, but its normally part of a fine art course.

There are many courses for framing, so perhaps to take a frame making class, to familiarize yourself with the type of carpentry tools used, as the methods uses to make a backing frame is very similar and perhaps the hardest part of canvas stretching. Mention to the teacher before attending the class that you would specifically like to learn how to stretch a canvas, and they may adapt the class to suit you.

If you decide to just get in there and do it, get good tools & materials. Common canvas stretching tools & materials are: Stretcher Bars, Canvas Stretching Pliers, Canvas Wedges, Ball Hammer, Drop Saw, Mitre Box, Staple Gun, Cotton Canvas, Stanley Knife, C-Clamps, D-hooks, Framing Wire, Gesso.

Canvas Stretcher - Further Career choices:
A good canvas stretcher with all round skills may go on to work in conservation framing, re-mounted artwork, they could also work for a printer, stretching prints on canvas, or they could adapt their skills and work as a framer.