Laser torpedo level makes the task easier.
Wrong nav lights.
Checking your magneto timing is part of every yearly condition inspection, but beyond that it is something you should be able to do whenever...
In an ongoing attempt to update his shop and make it more energy efficient, Jim Weir puts together a winning compressor-generator combo to run the lights and whatever else needs juice.
Basic mold making.
When you land your airplane at a fly-in, you want it to look its best while staying safely and securely parked. Making your own coordinated tiedowns, chocks and more is one way to do that.
Loose jam nuts.