I inherited a load of old tins of hammerite. I just tried to spray modern hammered finish over old smooth hammerite (which was fresh) I did this as I only had a single can of hammered (new) and loads of old smooth, so I figured I'd do the "work" of the job with the tinned stuff and get the finish from the spray at the end. ...I've almost finished taking it back to bare metal! The new spray instantly wrinkled up the finish. I'm guessing there has been an incomparable formular change or somthing? But now I'm not sure what to do. I have a tin of hammerite thinner acquired with the box of tins. But how do I know what paints this is compatible with? My 'in a hurry' back up plan was to thin down some paint from a tin and spray that, but I fear this all going wrong too. I don't have anywhere proper to do this work at present else I'd just get the 2k out. So I'm trying to "bodge" it - I'm aware of that, so please, no sermons!