Aluminum-Wood Stretcher Bars
Over the past few years, we have been designing and manufacturing custom hybrid wood-aluminum stretcher bars for some of our customers to meet their specific support requirements. Typically, aluminum stretcher frames offer advantages in the following situations:
- where large canvases need to be stretched on a relatively thin stretcher frame
- where exposure to large variations in heat and moisture levels exist (outdoor, tropical and cold climates)
- where tolerances for movement within the stretcher frame are very small
- where fire code regulations make the use of wood stretchers unacceptable
There is a misconception around the weight of aluminum stretcher frames. Many people assume an aluminum frame will be lighter than an all-wood frame; this is not usually the case. While aluminum is one of the lightest metals available, a frame made entirely out of aluminum will usually be 30% to 50% heavier than one made of wood. Aluminum stretcher bars can be made thinner than equivalent wooden ones but the weight will be greater.
The cost of making aluminum frames is also 40% to 80% higher than all-wood designs, mainly due to the higher cost of materials and machining.
The photos below show some of the wood-aluminum stretcher frames we have made. If you think that aluminum stretcher bars might be a good choice for your project, please call us so we can discuss the details of your artwork and installation.
96” x 120” cotton canvas stretched on wood-aluminum stretcher bars
1-1/2” wood stretcher with a 1” aluminum inner frame and 1” aluminum braces, shown disassembled
Assembled aluminum stretcher frame on 12 oz cotton canvas to be stretched
Assembled and disassembled corner of wood-aluminum stretcher showing design details and expanding corner turnbuckles used to add tension to a stretched canvas.
Centre splice joint (left), shown disassembled (below) and assembled (on right). These splice joints permit large canvases to be folded for easier transportation.
Squaring of corner is done by adjusting the corner turnbuckles
The stretcher frame can be expanded or contracted very precisely by adjusting the position of a threaded nut at the end of each brace.
Above are some examples of custom profiles involving the use of wood and aluminum in the design of stretcher frames.