mounting a painted canvas

Hi,

I have a painting I did (16X20) that I want to frame, but the stretcher bars stick out behind the frame I want to use. Normally I wouldn't mind but because of the wall it is going on it can be seen from the side and I don't want it hanging out that far from the wall. I thought of pulling the staples and mounting it to a thinner sheet of masonite but I'm not sure what to mount it with. Someone said I could use spray adhesive (something like Krylon makes) but I wasn't sure if that was safe.

Any ideas on mounting a finished painting on Masonite?

Thanks

I'd be hesitant to un-stretch a canvas only because I have never done it. I have painted the side of a canvas either black or a color that would blend in with the frame so it is not so visible when sticking out 1/2" beyond the frame.

The other think I have done is add strips of wood that match the frame along the sides that are visible, making the frame appear to be deeper while concealing the canvas.