Toman, there are a few aspects to antiqueing and although I am no expert I have studied it quite a bit.
You can try to make the varnish look old by its composition and layering. Mixing layers of oil and spirit varnish can produce convincing craquelure (crazing) quite easily.
You can duplicate common wear patterns eg: near the corners, the E-side upper bout, the centre of the back, bow wear on the C bout edges etc, either by thinning the varnish or even wearing it away completely in spots. Look closely at the Rossi bass at
http://www.rudolphfiedler.com/basses%5Cfull%5Crossi.jpg
look how the varnish has been scraped away across the front then covered with a lighter layer as if "touched up" over time. Also the faked bridge-foot damage. And you can put small dents and so-on in the varnish with a length of chain or the edge of a light hammer. If you really want to.
Then you can mimic the effect of dirt buildup (the famous bass smegma - remember
this thread? one of my all time Talkbass favourites!! ) around the scroll, under the tailpiece, the upper corners where you lift the bass with greasy fingers, and the rosin buildup on and near the bridge. I think this is one of the most effective methods, can be done with carefully applied darker finish.
And blackening the insides of the F's.
And the crowning glory would be the tennis-ball-sized fake bass-mouse rolling around inside!
Personally, I like antiqueing if it looks like the bass has been loved and looked after during its life. But the fake bridge-foot damage and chipped varnish just looks like the instrument has been knocked around carelessly, and I don't like that much.
hey Ken how's that cornerless bass coming along?