Here is a good view of the machine:
Side view. Good view of the brick. It balances perfectly as you can see.
Up close view of the bearings. Very simple design. Easy to build.
This is in the process of carving a sweet curly walnut guitar top.
The top finished.
One other useful aspect was to clamp the stylus down to stablize the router at a specific height and use it as a binding cutter. This only works if the binding is on one plane only as the router does not move up and down to accommodate arched tops and backs.