Vinegar will also remove metal as quickly as it does the rust.I tried it once and it turned a bunch of rusty bolts into a bunch of scrap metal after it ate all the treads off.Now I only use molasses and no issues even if I leave the parts submerged for weeks.
Another handy tip for using molasses...if the mix is cold (like mine now is as I keep it outside due to the smell) it works very slowly but warming it up to around 70F with a cheap fish tank heater will make it work much faster.