i found this stuff in a bottle at my LHS, is blacken metel, all most instantly. well i got 2 peices of atlas N gouge flex track done so far, here is what the bottle says..... cold chemical blackener for metals. blacken-it is an effective alternative to paint. no setting or curing time... weathered black finish. may be soldered over. no spray equipment required. not harmful to plastics. wont hide fine details. conducts electricity. ok, i put it on my track with a q-tip. after a little while it did blacken some. but there was spots that did not turn, i think i just need to go over it and hit the missed spots again. but im thinking of just highlighting the missed spots with an rust colored paint. now the bad part, (witch in one way is a good thing) the bad thing is i could not keep it off the top of the rails, so now there blackened to, but it conducts electricity so i can still run thr train on it......(i hope, im laying the first of my track today, so i will test it out today) now for the good part of having the top of the rails blackened,,,,,, you can use it on sidings and branch lines that like in the real world dont see much traffic, and are rusted all over, but you will still beable to run your train over that part of the track. where if it was paint you could not. has anyone else used this stuff? what did you think of it?