Yeah it will take a long while... Years for me. I just got my left arm a couple of weeks ago, I got my right arm four months ago, and started training them 2 years ago.
When I started I couldn't do a negative almost at all. I used a ton of methods, most of which are described in the beast skills article. Some people say tendinitis is unavoidable but I never got it...
Ryan, when I was getting close, some things that put me over the edge were training the iron-cross and really hitting my grip strength a lot.
Good Luck!!