I need help with the Lake of Fire level.  I put the fang together, the treasure chest appeared, and I got the centi-saw.  I cut the first wood piece.  The ball tried to break the three barriers, but Wiki said the ball needs more power.

I sawed down the other two wood pieces.  Then I sawed the wood piece supporting the other ball.  It rolled down, then fell into the lava.  How do I beat this level?  Please help me.  Thanks.