[fixit10101]

reading numerous post on painting, it seems everyone seems to mention sanding with a "da". Pardon my dumbness, but what's a da?

[milo]

Da is short for dual action... ... instead of spinning in a cicle the sand paper wheel has a circle in a circle random action.
Heres more ... ...New DA--Any recommendations?

[kenseth17]

I am guilty myself of always using the term, as I started in the late 80's when they were the norm. If you want to get technical I guess the term should be saying now that they are more common site in most shops then they were back then is random orbital. Many call them palm sanders, because thats the way most of em are. They are much smoother operating for sanding the exterior down, and can actually even straighten small areas of filler with them if you have enough experience. A dual action sander is what you normally see the chain stores selling and have a handle and a counterweight that can be moved to put it into grind mode. They are made by a lot of different manufacturers from good to cheap twenty something harbor freight models. I guess you could say these are better for roughing out work, although they can be used to sand a car, I've sanded many with them. The random orbitals the most popular are probably dynabryde and hutchins and normally cost a little more then a da.