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Hi Dennis, Well, I'm not an expert either but I do have some experience in automotive type painting over a number of years so I'll throw out my thoughts. 1. I am a little surprised you are painting your disc at all. Judging from the pictures you've posted it looks brand new, including all the warning decals :o). 2. Even "cheap" paint should not fall off if the proper surface preparations are taken (90% of the work, btw). The cheaper paint chemistries still provide decent protection to the metal and for some purposes are entirely adequate for the task. Because of the basic chemistry (not brand) of the cheaper stuff, there is a greater tendency for the colors to fade over time. Red is notorious for such fading; a nice bright red can look more like pink after just a year's time exposed to sunlight. The cheaper paints are also less resistant to chemical attack, particularly solvents such as gasoline. Even the cheap synthetic enamels were used successfully on automobiles in the '50s and '60s so they are up to doing the job of adequately protecting the metal. They are just not as "good", performance wise, as the modern, more expensive auto paints. 3. Automotive paints are not formulated or intended to be applied by brush. They are relatively fast dry and can exacerbate the problem with brush strokes, especially when done this way on large areas. I have used a brush with mixed auto paint for very small areas such as touching up bolt heads and nuts. I have also brushed a short length of logging chain. Where you plan on having your disc broken down into all the relatively small individual pieces, you might make out well with a brush application. For larger areas though, a slow dry synthetic enamel would be a better choice despite the poorer fade/chemical resistance. In any event I would not use a hardener without fresh air breathing equipment. While the exposure is less than spray application, it is still there and should be avoided. Your good health should be the most important consideration. 4. I suggest you review your goals for the disc. Is this going to be a show pony or a working piece of equipment? If it is a working piece of equipment and color matching is not an issue, I would consider saving some money and using an industrial enamel with brush application. I say this because you apparently don't have a spray gun yet coupled with the fact that there are no large visually important areas where an automotive type finish would be appreciated. Rustoleum would be a candidate. Benjamin Moore also makes a decent exterior metal enamel in bright colors, as do others. These paints are relatively inexpensive and are intended for brush application, although they can be sprayed. The so-called tractor paints are also a contender for this particular use. Just follow all the instructions that come on the can label. Personally I shy away from the rattle cans because I think the film build you normally get with 'em doesn't provide as good a protection to the metal as a brush job. 5. If you wish to pursue a spray application on your own, if for no other reason than to gain a little experience, I would recommend a small touch-up gun (also referred to as a spot gun). I say this because your disc parts are not large and you do not need the larger fan pattern plus your compressor per your prior post is of marginal capacity for a full size gun. It can be done with a full size gun but I think you would be happier with the touch-up type. They can be had ranging from about $30 all the way up to about $300. For a first time user on a piecemeal application such as yours, the $30 variety should do the job satisfactorily. If you wish to proceed this way then I would recommend what CNKS has indicated; the MP170 epoxy primer plus the MAE w/o hardener. DuPont's NASON line would also have similar products if that is a more convienient source for you. I have not used a NASON product but have no doubt that it would be comparable with the OMNI, although John down below indicates it would be superior. They are competitive "economy" lines. Get the tech sheets on each product and be aware of the time window on the epoxy - 3 days max for the MP170 to topcoat w/o scuffing and reapplying. NASON's may be different. This way would provide you with a better product at only a modest increase in cost over 4. above. These products can be applied with a standard chemical cartridge mask that is relatively inexpensive compared with fresh air breathing equipment. Therefore you don't have to compromise your health in the process.  Rod
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