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A local body/paint guy here suggested that I sand everthing with 180 grit to knock down the rust, then use an epoxy primer to seal it.





The 180 will do a good job at rooting out the rust. It will probably rough up the surface so that you need a high build primer to blend out the surface scratches/scars. The epoxy primer would give you the build up to accomplish that... but I would think you could use the Brightside primer or some other primer liquid in a can to accomplish the build up and seal of the bare metal surface. ( I am not a fan of the aerosol primers when it comes to sufficiently choking the bare metal surface from oxygen or moisture. The areosols lay on too thin a coat - compared to a rolled on primer that is 3 x 5 times thicker. The extent of the sanding into the metal may require a thin skim of bondo to level it out... as the thicker primer just may not be able to build it up level as efficiently as a thin skim of bondo ( which you would primer over after the bondo cures. )

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A quart of epoxy primer and a quart of the catalyst will cost me about $60, so I'm concidering other options, that being rustoleum. I checked at the local Home Depot and the quarts are going for about $8. There was also a rustoleum clean metal primer and a rusty metal primer.





Rustoleum/Tremclad or Brightside can all go straight onto metal and be pretty successful. But when you have scarred up the surface removing rust, it would be better to lay down a build up layer of primer. The paints will not be able to build up their coats evenly enough to mask out the sand paper scrathes on the bare metal.

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My current thinking is to do like the body guy said and sand the truck with 180 paper, then covering the whole truck and the good fender with the rusty metal primer, mainly because I'm not going to buy a quart of primer just to do one fender.





This seems like the root to go. My personal preference would be to use the Interlux Brightside primer - simply because I was impressed by its coverage and thickness when applied. It left me lots of room to work it with an 800 grit sand paper to smooth the primer down nicely.

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Another issue is that I will be doing some minor bondo work, which will require more sanding and primering. Can I do the bondo work over the rusto primer or do I need to take it down to bare metal first? Then when I'm doing the bondo work and trying to smooth it out, should I use the rusto primer or use the rattle can primers to sand with then finish with the rusto? I had planned on using a hvlp gun to spray the paint, will that work for the primer also?

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I think you have to approach this job in the logical sequence to get the best results.

a) get all your rust removal, overall body sanding and bondo'ing done. Surface prep is where this project is going to make it or break it.

b ) lay down your primer layer over everything. This will stop the bare metal area from rusting.. the bondo from sucking in the paint... and provide good adhesion for the rolled paint layers on the scuffed paint. If you spot any body defects once the primer stage is done.. sand the respect spots, bondo it... and then blend in primer over that spot. Sand the primer layer smooth

c ) start laying down your rolled paint layers as per the recipe we have been following for the roller method.

As previously noted... I think you will get better results using liquid primer that you roller... than the primer spray in the aerosol cans. You will get better coverage with the liquid that is rolled on - and as a bonus you will probably save money ( because the number of aerosol cans of primer will cost more overall then the cans of liquid primer ).

The problem with primer, painting and then trying to go back to certain spots to slap on bondo is that it will make to much work and extra coats of paint to bring that repaired surface back up to the same consistent color as the rest of the body. In some cases the catalyst in the bondo can cause the paint it touches to wrinkle, soften or shrivel up like elephant skin. So it is best to nail down your bondo and surface preparation before going for your primer and paint coats. It will just cut down on the number of opportunities for something to go wrong...

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Last edited by Marq; 06/17/07 11:41 PM.