Can shellac (Bullseye in this case)be used on new wood as a primer before painting with an oil paint? I used shellac as primer before brushing-on an oil-based color paint. I then used a 2nd color (this was a spray paint)for accents. The 2nd color immediately "crackled" - a nice look but not what I wanted. Is shellac a primer? Why the "crackle"?

Crackling paint and Shellac Primer