Hi Mr. Troels,
I just finished 3wc-10 speakers, so far I'm very happy with them. I am sending you a couple of pictures of the speakers in the process of making them, you can publish them if you like. I used BB plywood 21 mm and painted MDF, making them was challenging. I used the remnants of plywood to make a stand, and I also made front grilles. 
I have been following your work for the last ten years and I wish you many more successful projects. 
Marko, Croatia