From the woodworking site posted a couple of days ago, Matthias Wandel made one out of wood: http://woodgears.ca/marbleadd/index.html http://woodgears.ca/marbl

From the woodworking site posted a couple of days ago, Matthias Wandel made one out of wood: http://woodgears.ca/marbleadd/index.html http://woodgears.ca/marbleadd/index.html