John K Jordan
I don't think I would use a special light on a sander for scratches. That would require moving the sander around to light the surface from different directions.
I prefer a hand-held light for inspection. I've bought a bunch and my hands-down favorite hand-held light of all times is this
the Fenix model LD22. I think I have seven of them, in the car, shop, house, barn, for travel. I use them every day in the shop. It's the light I carry around the farm at night, plenty bright to light up a field or see to aim a shotgun. The first one I got some years ago still works perfectly.
Why do I like it?
- small diameter, fits nicely in pocket
- four levels, very dim to blindingly bright
- uses two universally available AA batteries
- a sensible on/off switch
- a well designed UI
The soft switch on the end can be pressed lightly for momentary light, clicked to keep on. A second switch changes the brightness. The UI doesn't let you accidentally switch to or force you move through those silly modes I might never use: SOS and flashing. (This aspect of a flashlight is a deal-maker/breaker for me.)
I track the price with CamelCamelCamel and buy when the price drops below $40.
I also use naptha, wiped on with paper towel - great for revealing defects, wiping away sanding dust, AND for showing what the wood will look like with finish.