Here is some excellent examples of using ABS filament and applying acetone vapor to smooth. In this example, I printed several baskets and a pot for my wife and daughter.
I was going to throw away this first basket as I had the fan settings incorrect. It is also a hard print due to many thin pieces. In addition, I did not add supports (scaffolding) to the base so the angles were extremely high, adding to the drooping and other issues.
Needless to say, I was blown away with the results! Depending on the amount of time you keep the object in the acetone gas, the more it smooths/melts the surface.
For strength purposes, the longer you keep the object in acetone vapor, the strong the object becomes due to all the layers melting together.
Here is another basket, and it is currently in a pot for acetone vapor. It has about 1/8th of an inch of acetone poured at the bottom. The object is elevated on a platform so it doesn't sit in the acetone. The inside of the pot is surrounded with paper towel so that the acetone wicks up the paper towel thereby allowing a better transformation over the air to the object.
This object was also hard to print due to me printing without supports (supports can make their own ugly mess too). There are so many high angles I was worried this print would fail.
After one hour
After two hours. 
It takes about 15 minutes before you can handle the object, but it is soft. I leave it outside for a day to cure.
The entire recent collection
