A quick progress report on the Nessie project. Like the previous Scotch Yoke mechanism there is a disk with a pin which sits in the yoke. As the wheel is drive round the slider is pushed back and forth.

The two slider tubes, left and right, are fitted so that they are as far to the side of the box as possible allowing room for the rest of the mechanism to fit into place.

The two humps of the Loch Ness monster will be rotated using a rack on the top of the box. My current, rather messy, prototype has the rack fitted to the top and one of the wheels working.

The head and neck will be fastened to the bell cranks front and rear. 

Looking good so far!