Is it safe for me to use expired acrylic paint on canvas? if not is there a DIY on how to rid the mold or whatever is causing the sour smell in the paint? (i really dont want to spend $30 on more gold,silver,and copper paints.)
It is "safe" but as the paint out-gasses it will continue to smell sour.
I used some older paint on a bathroom in a garage once and it continued to stink for months.
Only you can decide if the smell is worse than paying $30 for more paint.