Most ironworkers will run acetylene, not propane, the propane is a lot slower to heat up. I have both at my shop, and mostly use propane because I can fill it off my big shop tank, and its a lot cheaper, and I'm not usually in a big hurry, I don't spend all day cutting.
The propane takes a lot longer of heating to get started off, but once you get cutting its not bad. I have the best luck turning the propane kind of high on the knob, lighting, then adding oxygen, and finally turning down the propane to get the tip I want. Its less likely to blow itself out using that method - for me.
Sorry if the criticism seemed harsh, your posts on what your trying to do, seems to give the impression you don't know what you're doing. Everything I saw (110v welder, sample designs, issues lighting torch) pointed that your skill set might not be up to the forces that grader is going to put out.
I guess if I see something, I'm going to say something. Good luck!