engineshoppa

New cab corners and rocker panels are welded. Paint code achieved and enamel paint bought. I spent the day sanding the top coat (clear or base what ever toyota factory finish is) with 220 grit. The question is what do I do next? I think I am on the right track with a sealer next but do I prime the whole thing now of just seal and the spray the base on. If anyone has the answer put their 2cents forward please. What is a good sealer?

p.s. I have searched the net but am not getting a definitive answer.

here is a pic of the truck new front fenders, rockers, and cab corners.

snobdds

Well there are many schools of thought on this, but it really depends on what your trying to achieve.

If it was me, I would...:

Sand the entire truck down to metal and see where filler is needed.
Use filler where needed.
Sand everything down smooth...then do it again to feather the filler in.
Get some PPG DP-90, DP402, and some reducer. The ratio should be 4:1:1 respectively. This is the best exopy primer on the market. This will be both your primer and your sealer.
Apply 3 coats of this sealer/primer combo.

***Disclaimer***Some will say at this point it's best to apply an additional filler primer then block sand and then reapply an exopy sealant, but for a 25 year old truck, I skip this step.

After one hour of drying time on the epoxy, spray your top coat of single stage or (BC/CC). Epoxy primer is best to use because you can primer and paint in the same day. It's expensive, but well worth it.

nothingbetter

like the guy above me said, it all depends on what you want to acheive. This is the order we would use in our shop. ( not too in depth) Weld in Panels, grind/tap down seam, do the filler work, spray the primer, sand primer. Prep rest of are to be painted. Seal entire area. Apply paint following directions of the paint and sealer. Depending on what products you use you may have to paint over the sealer between 15min-and 6 hours or else you have to sand it all and seal it again. Different paints will fill different grits of scratch. Some paints will fill 180 grit, some have to be sprayed over 600grit to not show sand scratches if you don't use a sealer. So many variables.

engineshoppa

I am willing to do all the necessary work needed to do it properly. Do I need to sand down the new fenders as well?

nothingbetter

Is this your first attempt at body work? Anybody can do bodywork and paint, but it takes years of doing it every day for it to look good. Its not a job. Its an art.

yes. You NEED to sand those fenders. I suggest painting the inside too. Right now they're coverd in a factory primer with has very little protection as its applied very thin. you could use a spray bomb undercoating/boxliner as well. But there has to be something in there or it will rust from the inside out.

There are 2 types of adhesion that make paint stick. Mechanical, and chemical.

Mechanical is the scratch that you put in with the sandpaper. This makes "valleys" in the surface, essentially doubling the area that the paint has to stick to and doubling the amount of chemical adhesion. The paint is then sticking on many different angles giving it more stregnth. To deep of a "valley" (course sandpaper grit) and the paint won't fill them in, showing your sanding scratches and making it look like hell.

Chemical adhesion occurs on a molecular level. The paint "bonds" itself with the substrate thats underneath it giving it even better adhesion.

Paint sticks to sealer using mostly chemical adhesion. Which is why you have a time window you need to paint it in. Wait to long and the sealer will be to "hard" making it so the paint won't bond.

Sealing your entire job before painting gives it an even and universal colour that you need to cover. If you don't seal it, and don't apply enough coats of paint, the colour will be different where your primer is compared to where its not. When you apply your paint, you have to spray the entire truck in one go for each coat. If you put an extra coat in a few spots because its not hiding well, you'll have areas that look darker where you sprayed that little bit extra. Temperature and humidty among other things will also effect the value (lightness/darkness) of the paint. Same with how heavy your coats are, and how you apply your drop coat if it has metallics will all effect the final colour. Thats why you can't just give a painter a code, say "paint this door" and have it come out the same colour as the fender its beside. If you and I sprayed the same paint through the same gun in the same conditions at the same place, the colours would be different.

Wow, didn't think I would type THAT much.

nothingbetter

p.s. pull your door handle too

engineshoppa

Thanks a lot for all the info guys. Yes the insides of the fenders are already painted, grandpa showed me that trick. Door handle is going to come off, forgot to bring the inner door handle clip tool home, didn't feel like fighting with the jesus clip with a screwdriver.