I don't remember Walter posting it on Hometalk, but he has a link to a video about making one here:
my house is being over taken by the carpenter bees this year!
They are now coming out twice a year....best defense is a fresh, quality paint job on your trim with the borer bee retardant we started adding last year. We took an off the shelf product and modified it through trial and error...what we have now seems to be working and we put a 5-year warranty on borer bee damage....they damage what we've repainted and we'll fix it for free
You see the little hole they drill in your siding but you'll be amazed at the tunnels they carve inside your trim!
You would be amazed at how many i have played baseball with the past two days. My batting average makes Chipper Jones look like a little leaguer!
It won't do any good....they are destructive little buggers....good for my business though! It really is amazing how they carve out those tunnels