I've usually done this by using an electric drill-mounted wire brush, follo wed by whatever manual scraping tools come to hand (chisel, screwdriver, wi fe's best knife set) to get the fiddly bits. The thing is, it takes ages an d I have four or more quite large gates to do.
What is the sensible way to proceed? Hire a sand blaster? Pay a chappie to collect, blast, prime and paint? Is there a particular tool that would make it easy to get into the nooks and crannies? I don't fancy spending the nex t few weekends doing this hateful task.
Cheers. Terry.