This technique works for linen and cotton canvas. Unfortunately, if your canvas is made of a synthetic fabric, you won't be able to do much, at least as far as I know.
However, if the problem stems from a poorly applied or low-quality primer, the problem is likely to recur.
Or a sponge
Or a kettle
Heat the water in the saucepan.
The water should be hot but not boiling.
Soak your cloth in hot water, then wring it out well.
Moisten the inside of the canvas (frame side) with the cloth.
Just dampen it, no need to flood the canvas!
Use the hairdryer to dry the fabric, always on the inside.
Move back and forth, and avoid staying too long in one place to avoid burning the fabric.
The fabric will tighten.
If you find that the canvas is not tight enough, you can repeat the operation.
During the year, I organize various workshops and courses to learn how to make your own paints.
I've collected websites and books dedicated to making paints, stains, inks and other artistic materials.
I'm selling some of my creations.
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