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Hi Dave, Ditto what CNKS said. I have never used the NAPA paint products, marketed under the Martin Senour brand. I think their Crossfire line of paints is an economy one, similar to PPG's OMNI or DuPont's Nason. You can get all the specific usage information on particular products here. Just click on "PDS Catalog" to bring up a .pdf index file of clickable links for individual product data sheets. Those will provide the detailed usage information for each product you are using. In general, I think that any polyester filler (such as bondo), even the "finishing" versions, should not be used over a paint product unless that product is a 2-part epoxy or unless the filler manufacturer specifically recommends it. If the primer/sealer you used was an epoxy, then you should be OK in putting a filler on top of it (within any stated time window of the epoxy). That's the way I have done it successfully. If not, then I would tend not to do it. There would be a question of satisfactory adhesion of the filler. It might be OK for small scattered pits but I have never done it and can't vouch for it. There are the acrylic lacquer spot putties also. I have used them for some shallow pits a few mils deep but I don't think they would be the right choice for deep pitting. The best way to handle deep pits really is with the 2-part polyester "finishing" putties, either directly on a sandblasted surface or on top of epoxy within the appropriate time window. Usually any of the paint chemistries are applied in several individual coats, allowing only a few minutes (typically 10-20 minutes) between them. Some products only require a single coat but most color topcoats require two or three. The individual product data sheets will recommend the number of coats and the time between them, know as "flash time". I am not surprised the parts man didn't advise you of the issues (dangers) with the use of isocyanates. I am not impressed with most of the paint salesmen I have dealt with. It's really up to you to do the independent research on the various products available and decide what is best for your individual case. What is "popular" in the bodyshops may not be appropriate for an individual or a specific need. There has been a lot of past discussion in this forum on the iso issue. Do a search on isos or isocyanates for some opinions. Also check out the material safety data sheets (MSDS) for each of the individual components used. This MSDS information is also available at the site noted above. Those sheets will give the manufacturer's recommended safety practices you should consider using. Isocyanates should be anticipated in the hardeners (if used) in the topcoats and many primer-surfacers. The only two-part primer that does not contain isos is epoxy, as far as I know. I always use three coats for my topcoat color on all surfaces. You might get by with two but I would figure on using three. Again, it depends on your exact product - so check the specific data sheet. The biggest differences between auto paints nowadays and those of thirty years ago is the current widespread use of urethanes and iso-containing materials, the usage of basecoat/clearcoat two-stage systems and the essential disappearance of lacquer as a common finish.  Rod
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