Oil or acrylic on canvas that has been properly varnished by the artist should be stretched onto wooden bars and without glass as oils can take up to 40 years to dry and therefore need to breathe. We use specially profiled bars that have a ridge to reduce the area of canvas in contact with the bars.
For customers who require canvas blocks (i.e. no rim to frame the edge of the bars.) the canvas is stretched neatly with hospital corners and stapled to the rear of the frame, completed with tape, D-rings and cord ready to hang. We can also complete the sides by painting them to a neutral colour.
Painted boards of acrylic or oil are normally framed without glass and backed with a second securing board, which strengthens and stiffens the existing board to keep it rigid for years to come.