I use acetone for abs, I also use it to form a slurry that is spread very thinly on the glass bed of my printer to help the parts stick. you can buy small bottles at most chemists, or by the liter online. for joining parts just spread a thin coat on each part with a brush , then press together. acetone is also used to smooth abs parts from the printer, parts are put into an enclosed space with acetone fumes, for as long as it takes to slightly melt the surface, then removed and allowed to set again.
note test on an inconspicuous area or piece of scrap first