Today I received my latest Goodwill auction win. It's a ball head mount. I plan on making a plexiglass piece to fit in one of my train cars so the mount can be used to put a camera on for 'on board' videos.
I needed to clean up my attempts to cut the plexiglass so this is my version of a router table.

It worked out well as I was able to file the plexiglass to fit in the train car. Classic slip fit with no discernible movement once it's in place.
I still need to drill/countersink the hole for the attachment, but it's time for football now so that'll have to wait.