How to Make Log Ends Perfectly Flat & Parallel

I like to make stuff out of logs, and lately I've done a couple of projects where I needed the ends to be perfectly flat and parallel.For most log projects you could probably just use a chainsaw and get the ends close enough. However, when "close enough" isn't good enough, here's the method I use. This requires some scrap plywood and basic tools like a router, drill, level, and clamps.