Here's the basic layout of the folded horn. I used Auraco pine for the exterior panels as everything else is pine. It's definitely A/C grade as demonstrated by the big knot void. Started curling up the minute I cut it. The rest is baltic birch. The baffle is 1/2" thick for the OD. The driver mounts to 3/4" baltic.

Here's a different view showing the layout lines. All structural members use PL Premium adhesive. Disgusting to work with but very strong and forgiving. Slow dry times. I love the black fingers when you get it on your skin.

Here's the third panel installed, I rotated the picture for saving some space. The short stick at the right is temporary to hold everything in place.

Here's panel 4 it ties #3 to the baffle and closes the back chamber to the driver. The small blocks are keeping it aligned until the adhesive cures.

Here you can see panel 5 installed an the beginning of the path for the horn wrap. It's also a good time to feed the wire into the driver chamber. I used some heat shrink over vinyl tape to fill out the wire hole. Some hot melt on both sides to seal it up. Leaks from the back chamber will severely compromise performance.