Honestly.. I wait about 10 minutes. I know lots of people in here think it takes more time, but I just don't see why. I use a Canon, so perhaps these inks don't outgas as much, but the big thing with canvas is that it can still outgas from the back. I put on 3 coats, maybe 5-10 minutes apart and after about 30 mins from the last coat, the canvas is pretty much dry. I wouldn't roll it up mind you at this point, I would let it dry overnight, but its perfectly fine to touch and move it at this point and even stretch it. I spray with a mix of matte and gloss timeless.
I seriously don't understand all the issues people have with canvas and spraying. The fact that my ratio of matte to gloss is 4:1 makes spraying easy as the lack of reflections of the surface makes you not have to be as careful when spraying, so if going with full gloss, there certainly are issues there, but other than this, spraying canvas is quite easy. I don't have a fancy gun either, just the Wagnar HVLP.