Yes,loco set at about half speed,nice dry an wind free day,spray can held at slight angle about 18"away,and angled slightly toward the model,this allows cab front etc to catch some,aimed at about top of wheel height,or lower,as the loco runs by,hit the can,the loco runs through the spray,one pass;then do same other side,let the loco run 5mns or so,so "dust" dries,this effect gives constant cover on the wheels,do as many passes to get required effect,then run loco in reverse,(i leave tender off)and one pass normally does it,this picks up the rear of any details so all gets covered,the greater the distance the spray can away from the model,the greater the dust effect,and the greater the coverage area.once happy with the effect,keep a mental note of the number of passes,then,off the track, pass spray over rear of cab,front and rear of tender,keeping the angles the same.rear of tender trucks and details get done now,First time i tried this,covered a box car in cartridge paper,and ran it behind couple of old flats,figured out the spray angles,two things,,,,,,,one,using this method,track gets a weathering,mask ties if you dont want,and two,lube all moving parts before spraying,then paint wont stick to oiled parts,will wipe off.COLOUR used is Humbrol dark earth,(29 i think)If you check out my posts in the BASHING section,Otto,Stainz,and MOE,all done using same method.I was after the dirt to be greater at the bottom of model,than at the top,as if up from the track,wheels etc,then lay loco on its side,matt black along its length,little soot!if you try it, HAVE FUN!!!!