I am trying to build a lugged frame bicycle with Columbus SL steel. I am new to brazing. I read in "Designing and Building Your Own Frameset" by Richard Talbot that it is possible to braze a lugged frame with propane. After trying to braze the head tube/down tube I cleaned off the flux with hot water and checked my work. It was clear to me that I didn't use enough heat and there are gaps where the silver didn't flow through. Am I screwed now or is it possible to reflux and reheat it with a hotter torch to fill in the gaps? Maybe this is a dumb question, Im just not finding a lot of info on what to do if you mess up..