I am working on a restoration project that requires filling large cracks (2"deep, 1-2" wide and up to 5ft long) in painted cedar beams. The beams will be repainted after filling. I have used Bondo in the past for similar smaller scale situations which has worked well. Given the scope of this project and time constraints I would prefer not to mix and fill with this much Bondo. Does anyone know of a filler that could be used to fill the majority of crack first and then coated with Bondo to finish? I had thought of using expanding foam, but this may react with the Bondo and leave a gap between coats. Any suggestions? Also note this is purely for aesthetic purposes, not structural. Thanks.