I took a 4x4 and cut an angle up hole on one side straight to the middle and then another hole from bottom side straight up so they intersect and then attached a glass jar to the bottom.. I can see them going into the angled hole but they never come out the bottom into jar..
They fly in through the angle up hole and think its a previous bore done by them or another bee. Then inside they can fly around and will fly "down" the light of the clear jar/bottle.
Old man who introduced me to the traps swore a carpenter bee will never "bore" down...if he is right that may explain why yours arent going down into the bottle.
Im a softie for the bees though. They fly into my jar and my kids take them down the road and let them out....
I dont build mine out of a 4x4. I build a "birdhouse" with a (cue donald trump voice) huge chamber.
The up hole is drilled steep enough to allow no light to pass into the "box" so they fly down to the light of the jar.
My wifes parents house has cedar siding so they have to deal with the carpenter bees every year. We have had several of them boring holes in some cedar beams on our front porch. My FIL has a special tool to pump drione powder into the holes. I borrowed it today. Within a couple of minutes bees started coming out of the holes and would fall to the ground and die. I tried one of those common wood and bottle traps, but only caught two of them.
I took a bag of sevin dust, a bored 8 year old and a turkey baster to the shed last weekend. I started out powdering the holes while she stood back and pointed out the holes. It soon progressed into her running around stomping bees as they emerged and half heartedly tried to fly away. We were not sure of the total death toll because it got pretty intense at one point with her slapping one clinging to my back while I was slapping one to death that had fell/flown into one of my cargo pockets. It was a good day for victory!!