With the new 4 Ah battery, we get almost 30 minutes on a full charge at top speed. First we sand the putty, not the wood. I've used this on wood, but when I need to sand wood for longer than 30 minutes I use a belt sander first and then finish with this sander. The weight can be a little heavy and you can only grab from 2 sides, but that's not a problem. You can take it two ways: with the bag on, which works for most uses, or I sometimes turn it so the vents are out of the way and remove theโฆ