I'm going to paint a truck frame and attached parts with Por-15 and would like to know if there's a cheaper product that I could buy at Lowes or somewhere else instead of their metal prep. Looking good isn't a major concern but I just want to stop the rust.
The easiest way I have used it is to pour it into a spray bottle and go to town. Yes the odor can be tough but it's cheap and works very well. I would take a wire brush and knock off as much loose stuff as you can before you start with the vinegar. Stuff runs about $2-2.50 a gallon. It works best if you can keep it soaking but I have found on large pieces that a good spray every hour or so works too. Once the rust is neutralized, give it a good wash with plain water then get it dried out. It will surface rust quickly in high humidity so once it's dry, you need to get started with your Por-15 which is great stuff. Just plan your work.