Superglue has great pull strength but does not take a beating. One little nudge and it could be broken again - and you would have to
sand away the glue residue before trying again.
I would not use acetone directly. I don't think it is strong enough solvent and it does not fill gaps. Instead, make "ABS sludge": put scraps of ABS in a air-tight jar and cover with acetone and let sit. The result should be a bit like toothpaste in consistency... but will however quickly degenerate to chewing gum consistency with exposure to air.
You should not lay it on too thick, or the acetone will never evaporate.
Even better might be
Devcon Plastic Welder - from its datasheet I have read that it is a bit like ABS sludge in a tube but made with stronger solvents than acetone. I have never seen it over here in Europe, so I have not tried it myself but I have heard great things about it on the forum.
I usually use "plastic cement" that is actually mostly solvents, and that is probably what I would use in this case. You can many different kinds in hardware stores and in stores that sell plastic model kits.
Apply to one part and then rub the two parts together a little bit before you let it sit or clamp it together.
I prefer the Humbrol Poly Cement in yellow bottle with the long nozzle. It runs, and evaporates quickly however. Humbrol's in a tube is a bit too runny and difficult to apply but should be the same as in the yellow bottle. Don't get Humbrol's glass bottle with brush - it will evaporate too quickly and once the bottle has been opened for the first time it is only a matter of time before all of it is gone.
For larger fillings, I prefer a two-part clay-like "epoxy putty" such as Milliput because it has much longer time than Bondo and can be used for sculpting.
For smaller fillings, I often use a one-part model putty, but from what I have heard Bondo's one-part spot putty should work just as well.
These are also found in stores that sell plastic model kits.
There are also
lots of older threads about solvents, abs sludge, adhesives and fillers on the forum.