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HOW TO - Stretch a canvas... | Make:
Quick and easy how to on Apartment therapy "Stretching a canvas is easy. You take four planks of wood, make a rectangle and pull the canvas over it. (Or pay framing stores a lot of money to do it for you...). Before you get frustrated starting from scratch get ready made heavy duty stretcher bars (best & cheapest:Utrecht Art Supplies). Their ends fit together so precisely that you don´t need glue or nails. Asembly time for the perfect rectangle: 60 seconds." Link.