A few years ago, I cobbled together a parts cleaner made from a plastic tub
(a cat box?), aquarium heater, small aquarium pump and Simple Green
degreaser. Worked very well, but not as good as real solvent. Leaving parts
to soak overnight was not an option due to rusting, but it worked OK for
bicycle parts. Nice thing was that there was no toxic fume problem and could
be used indoors without ventilation.

Keith O