Thanks again Senrak! I sent an e-mail to Sig about my question too. Within a few hours, I received an informative response. It sounds like I am using the right piece of balsa. I was also told that this piece is so strong that it doesn't matter which way the grain is running. Nevertheless, I took your advice and glued two pieces together. You can still see where the two are joined. Here's what the finished piece looks like...