Strip and Repaint


Why remove the existing paint?

There can be many reasons for removing paint before you apply a fresh coat but the most popular reasons are (1.) the existing coat of paint is no a good foundation for the new paint because it's cracking or peeling or (2.) the existing paint will react poorly to the new coat of paint.  Either of these reasons are good motivation for removing the existing finish.  The job shown below was stripped because the vehicle was repaired several years ago and repainted using lacquer primer and lacquer top coats that didn't hold up well.


You can see in the picture above that the lacquer painted panel has started too come off while the original painted panel above is still in good shape.


This second picture shows a close-up of the failing paint but this can also come in the form of cracks or peeling.
 


Area like the ones above are typical of lacquer primer and paint.
These are sanded when the paint is stripped then Picklex-20 is applied
to convert and neutralize the rust.

 

How to remove the Existing paint?

We've found that stripping entire panels using a sand blaster  is too messy and can easily damage the metal while chemical stripping is also messy and difficult to clean properly after stripping.  Plastic media blasting is best but needs to be done using expensive equipment so it's usually farmed out and expensive. 

Several years ago we discovered we could strip a car quickly and inexpensively using a good variable speed sander/polisher and good hook and loop sanding disks.  We tried stick-on disks and inexpensive sandpaper but found it to be much less work and much less sanding when high quality hook and loop paper was used.  We can now strip about 90% of a car using this method in about 8 to 12 hours under normal conditions.  The other 10% of the paint is usually removed using a smaller sander, a small blaster or chemicals.

The sander can quickly remove several layers of material as long as it can rotate slowly (usually 1000 RPM or less) so that it doesn't heat the paint or metal.


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Above the car is shown with the fender and both doors stripped.  Notice that the bumper is masked with several layers of masking tape to protect it from being damaged during the stripping process.

We've found that 80 grit disks work best for most stripping processes because it leaves a scratch that allows the primer to bite the surface well while still easy to fill with most epoxy or filler-type primers.

 


Body Work

Minor body work can be done after the paint has been stripped but if major repairs are needed or the work is going to take longer than a day or two you should prime first THEN do the body repairs.  If I were to need metal work or filler on a panel after it's primed I normally grind the primer off first but here I only needed to fill the door dings with a little polyester putty.

If I need to spend time doing body work or I need to leave the car sit for days I'd coat the bare metal with Picklex-20 to protect the metal from "flash rust"



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Masking is done prior to priming and can be removed if the primer is going to be left of the surface for a long period of time.  On this particular vehicle the primer and paint are going to be done using the same masking job.

 
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After primer is applied guide coat is dusted on top.


 

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Sanding

When using guide coat any small dents that were missed show up during the block sanding of the primer and can be scuffed, filled`then reprimed.

The primed panels are block sanded using 400 wet sanding paper but 600 wet paper is used for the final sanding prior to painting so that the surface scratch won't show in the new paint.   Since the rear quarter panel is to be blended we scuff the area to be coated with color with the same 600 grit sandpaper.


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The remainder of the quarter panel is sanded with a finer grit (1000 to 1500) so that the scratch won't show in the thinner, blended color or clear.


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Painting

As the primed panels are sprayed the quarter is sprayed near the primed panels so that a better match is achieved as you attain good coverage.

After coverage is achieved the clear is applied.  If you are trying to match the existing finish you'll want to try to match the texture as well as the color.  If the clear is applied too rough it can most likely be sanded with ultra fine sandpaper and polished to a smoother finish with buffing compound and the same sander/buffer that was used to strip the paint from the car.  A finish that is too smooth may need the vehicle's finish polished so that it matches the new finish.


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The match is good between the rear door and the quarter but with leaving the orange peel it still looks a little too good and I may decide to repaint the rest of the car.

 

Strip and Repaint
Door Handles

 I couldn't bring myself to put these door handles back on looking so old and beat so I removed the paint by using a small blaster that not only removed the paint quickly but also etched the chrome making it ready for epoxy primer and paint.  Hey, you got to look at these things every time you open the door so even on quickie jobs it's gotta look good in areas that can be seen easily.

Disclaimer: The ideas and methods described in this web site were developed under unique situations. Since these situations cannot be duplicated, you may get different results. Use and application of any of the site's content is at the user's own risk.

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