I buy pre-made canvases, and they always come with a little packet of wooden things:
What are they for? How should I use them?
I buy pre-made canvases, and they always come with a little packet of wooden things:
What are they for? How should I use them?
These are called "canvas keys".
The are shimmed into the corners of the canvas to maintain the tautness of the canvas. This generally happens only on machine-assembled frames, or on mass-produced frames that have low-quality inspection standards (for cost).