Weathering vehicles

Playing a bit of catch up here.  Took the photos and then didn't upload them.  I wanted to post an example of weathering powders.  I'm happy (mostly) with the finished work on the Vendetta.  Big model and you had to paint it in pieces so you needed patience with this one.  Having finished it, and happy with the Russian MiG look I was going for, I added the weathering.  Dirt along the base and leading edges, and rust/backwash on the tail cross bar behind the engines.  It looked great.  And then I sprayed on the sealer and the weathering mostly we bye bye.   So, here's the deal with this as others have commented.  Seal before you put on the weathering, then weather, then really lightly over seal.  Otherwise the sealer will blow away your wonderful looking weathering.