You'll recognize him as Tim Allen's co-star from Home Improvement and Tool Time, but today you'll get to know him long before he landed that role. Today's episode is with the hilarious Richard Karn! David and Richard talk about how it all began and what the Big Idea really is.

Don't forget to go to www.masterspas.com/BigIdea for a chance to win a $15,000 premium spa from Master Spas!