Originally posted by Emopanther:

You can hide Iron beam inside Core wood and Darkwood :o

After you are in Iron age. I start building my bases in stoneage. Its really annoying that you have such a hard time to Build a framework in that Stage. And btw you cant place the Metal beams reliable into Core wood logs because you need to remove these logs to do that, and removing these logs result in a Collapsing base