Remove Scratches Using the Porter Cable 7424 Polisher

Dual-action polishers may
not be able to completely
remove all scratches.

    Dual action polishers trade safety for ultimate paint cutting ability. Since the pads oscillate (jiggle) rather than rotate, dual action machines can not abrade away enough of the top clear coat to completely remove deep scratches. On the plus side, this random, oscillating motion makes dual action machines very safe for novice users. It is virtually impossible to damage the paint or clear coat with a dual action polisher.

    Since we are working on a small, specific paint defect, I chose to use the Spot/Scratch Repair Kit which includes a 3-1/2 inch wool compounding disc and a 3-1/2 inch White Foam Polishing Pad. Using these smaller pads gives me more control over the area being compounded and leaves surrounding areas unaffected. If I were removing swirls or scratches on an entire panel (i.e. the hood) I would have chosen full size wool discs and foam pads.

Product requirements:

• Porter Cable 7424 polisher
• Spot/Scratch Repair Kit
• A compound such as Menzerna Intensive Polish, Meguiar's Medallion Premium Paint Cleaner or 3M Fine Cut Compound.
• A finish polish such as Menzerna Final Polish,  Meguiar's No. 9 Swirl Remover or 3M Perfect-It Swirl Mark Remover
• Your favorite wax or paint sealant.

Procedure:

Scratch directly above driver's door.

Step 1 - Compounding

• Place the 3-1/2 inch wool polishing disc on the  2-3/4 inch backing plate and attach to your machine polisher using the adapter (if needed).
• Work on a small area, 12 to 18 inches square, out of direct sunlight.
• Apply compound directly to the surface.
• Mist the wool disc very lightly with water.
• With the machine off, spread the compound (i.e. Menzerna Intensive Polish, Meguiar's Medallion Premium Paint Cleaner) over the surface using the wool disc. This coats the wool disc with compound and reduces compounding paint temperatures. 
• Press the wool disc against the paint and turn the machine on. Set the speed dial on the Porter Cable polisher between 3-1/2 and 4. 
• Work the pad over the surface in a figure 8 pattern. Go over the area in a left-to-right figure 8 pattern and then an up-and-down figure 8 pattern.

Apply compound to blemish.

Put 3-1/2 inch wool disc 
on 2-3/4 inch backing plate.

Mist wool compounding disc with water.

Spread compound with machine off.

Set the speed dial between
3-1/2 and 4,

Apply compound in
a figure-8 pattern.

• Go over the area several times or until the compound starts to dry.
  
• Inspect the results. Spray the surface with a 50/50 solution of Isopropyl Alcohol and water to remove compounding residues and wipe the area dry with a clean Microfiber towel. (I mark one of the water bottles "Water/Alcohol" with a Magic Marker to keep them separate) Run your fingertips over the surface. Is it smooth? 

Remove residues with an alcohol/water
solution and inspect the surface.

• Has the scratch or paint defect been removed? If not, repeat the compounding and inspection procedure until the scratch is removed or until no further improvement can be observed. When the surface is as
•  defect-free as you can make it, proceed to Step 2, Polishing.

    Compounding may leave the surface dull depending on the abrasiveness of the compound used. This is normal. This dullness is removed in the next step which is polishing.

    Polishing is done after compounding to remove compounding haze (surface dullness). Polishing restores surface gloss and prepares the surface for waxing.

Step 2 - Polishing

     The procedure for polishing is exactly the same as for compounding with two exceptions. 

• Use the White Foam Polishing Pad for this step with a finishing polish (i.e. Menzerna Final Polish, Meguiar's No. 9 Swirl Remover).
• Mist the white foam polishing pad with water, spread polish over the area and polish in a figure-8 pattern. 

Switch to the white polishing pad
and apply a non-abrasive polish.

•  To test for results, wipe off polishing residues with a clean Microfiber cloth and inspect the surface. (Do not spray the surface with the alcohol and water solution.  This would remove fillers and gloss agents that you want to stay on the surface.) 

    If the surface is still dull, continue polishing. When the haze is removed and surface gloss looks good, proceed to finishing.

Step 3 - Finishing

    After polishing, finish with your favorite wax or paint sealant/ protectant. You can do this by hand or use the appropriate pad or bonnet for your machine polisher (not supplied in Spot/Scratch Repair kit). 

    When you're finished, wash all pads in a bucket with soapy water, rinse thoroughly with a garden hose and allow to air dry. Do not machine wash or dry pads.

Apply your favorite wax or sealant.

What kind of results can I expect?

    In all cases, this system will produce better results than could be accomplished by hand. Using a circular polisher will completely remove swirls, scratches, paint defects and acid rain, water spots. Using a dual action polisher will remove minor swirls and visually reduce deeper swirls, scratches and paint defects. It may not be possible to completely remove deep swirls, scratches and acid rain water spots using a dual action polisher .

Just a faint trace of the scratch remains.

    It was very hard to photograph the remaining, faint line. Most people would consider the scratch completely removed. It might be visible under certain light conditions (flourescent lights) but is completely invisible from a distance of 3 feet. This is the best that can be accomplished with a dual-action polisher. Further improvement would require a circular polisher (Makita 9227, Dewalt 849). See "Removing scratches with a circular polisher."

You should not attempt to remove
scratches that go through the
top clear coat.