I have been using isopropyl alcohol as a base for washes for some time now with great results. The alcohol is tinted with india ink (black) and can be used by itself or mixed with acrylic paints. because of its quick drying qualities the wash can be added to in fairly rapid fashion and achieve great depth of color. This is especially true in adding rust or grime on your AFV. Lately, on German AFV's rather than straight burnt umber and alcohol I will mix in some original base color. The result is depth without blaring contrast. Another great advantage to this is that the alcohol will not attack plastic, nor your base color.

I have read a couple of account where a modeler was applying a final oil based wash and watched in horror as parts 'melted' and fell off. In the several years I have used alcohol, no melted parts, no problems - try it you will like it...

Tried it many years ago mine came out to dark and the Ink could not remove it .So what ratio have you used just a real fine tint? (:-)

Sounds a very plausible idea. Why not? Everybody has their own preferred method and if your happy with the end result it has worked. If we are happy with your end result we want to know exactly how you did it!
I guess its experiments and different approaches like this that make this hobby interesting and a neverending learning curve!

Ratio - Using an eye dropper I add ink until the alcohol begins to change. Too dark and the effect is ruined. Also the alcohol/ink is to be added to the acrylic paint and not used by itself, so the ink is there to help you see it. On Panzer Yellow, I have been mixing the alcohol with the yellow, making a muddied yellow/gray. This adds depth but does not darken the tank.