It is inevitably nerve-wracking embarking upon an untested idea. Below, you will see the cardboard I practiced on to see if the glue was the correct consistency and then to test the effect of the shellac. An unexpected shower wet the cardboard but this is all right. I discovered that the shellac protects very well and even the column on the left, glued only, is holding up. It's the cardboard that is having trouble.
Having a cat that has philistine tendencies is something to work around.