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Bobby G
03-27-2002, 12:54 AM
by David W. Bynon

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You’d be hard pressed to find a car on the road that does not have paint chips and parking lot scratches. While good detailing practices can’t prevent nicks and scratches, repairing them will restore your car’s “like new” appearance. In this article, I discuss the methods I’ve used for years to repair chips and minor scratches.



What’s Possible, What Isn’t _

Touching up small nicks and scratches is well within the skill of most do-it-yourself car enthusiasts. Some nicks can be quickly repaired with a small dab of touch-up paint, while others will require more time, effort and skill. It’s important to know what you should and shouldn’t tackle based on your knowledge of paint and tools.



By far the easiest colors to repair are black and white. Black and white are very forgiving on shade variations. Conversely, metallic paints (those with metal flakes) can be quite difficult to match perfectly.



Before you get started repairing nicks and scratches, you should know what to expect. Small nicks are easy to repair by filling the nick with paint, leveling the filled area, and buffing the repair area to blend and restore luster. Repairing small scratches, from a key or shopping cart, is similar, but more time consuming. Fixing a ding (a small dent which may or may not have a nick out of the paint) is not commonly possible by the do-it-yourselfer.

Here are some other things you should know:



If you know your car’s factory paint code, you can purchase an exact color match touch-up paint from your local dealer. If you don’t know the factory paint code, look in your owner’s manual for the location of the code, or ask your dealer. If you have a late model car, chances are you will find a color match at your local auto parts store.



Use a small artist’s paint brush (#2 is ideal) or a round, wooden toothpick to apply the touch-up paint, not the fat brush included with the bottle of touch-up paint.



Always test the touch-up paint for color match in an inconspicuous area.



The area to be repaired must be perfectly clean and free of wax, rust and oils.



Don’t attempt a touch-up if the temperature is below 60 degrees F._



Here’s what you need to properly repair nicks and scratches:

* Color matched touch-up paint

* Automotive or metal primer

* Citric acid based cleaner like P21S Total Auto Wash

* Prep solvent (Prepsol) or denatured alcohol

* Foam swabs (from electronics supply) or pop swabs containing alcohol

* Meguiar’s Unigrit Sanding Block and 3M 1200 grit wet & dry sand paper

*_Medium grit hand rubbing compound

*_#2 Artist’s paint brush and round toothpicks (wood)

*_Cotton terrycloth towels

*_New Pencils with unused erasers

*_Rubber cement

*_Plastic cups

*_Blue masking tape (easy release type)

*_Large diameter paper hole punch (hand type)



Preparation Process _

Before applying paint, you must prepare the chip to accept paint. Although paint may adhere for a while to a chip with rust, dirt or oil, eventually the repair will fail. The preparation process begins the day before you repair the paint chips and scratches.

The afternoon before starting your chip repairs, wash your car. After washing with your normal car wash, spray the areas you plan to repair with P21S Total Auto Wash, allow to sit for a minute, then scrub well with your sponge. P21S Total Auto Wash will remove all wax and oil from your paint. Dry your car thoroughly and put it away for the night.



After washing your car, make up several sanding pencils. Use a hole punch to punch out a few dots from the 600 grit wet and dry paper. Apply the sandpaper dots to the end of your pencil eraser with rubber cement. Allow them to dry over night. You will use the sanding pencils to scuff-up and clean out nicks._



To make a chip ready for touch-up paint, you must make sure it does not have loose edges, clean it and sand it. I use a toothpick to check the edges of a chip. If loose or lifted, I use the toothpick to knock off the loose paint. To clean, I like to use denatured alcohol or Prepsol and a foam swab. I pour a little bit into a plastic cup and use a foam swab to clean the chip and surrounding area.



Next, I use a sanding pencil to cleanout the chip and rough-up the edges. Simply dip the sanding pencil into a cup of clean water, dab a few drops of water on the chip, and gently rotate the sanding pencil over the chip. Keep the area you sand as small as possible. Rotating the sanding pencil back and forth in your fingers 8-10 times should be enough to do the job. If the chip has exposed bare metal, or if you can see rust forming, use the edge of the pencil erasure to remove the rust. When finish sanding the chip, dry it with a terrycloth towel and clean it again with Prepsol and a foam swab.



The Touch-Up _

Once the damaged areas are cleaned and prepared, you can begin the touch-up itself. If a chip exposed bare metal, you must primer the chip before the color touch-up. After mixing thoroughly, pour or spray a small amount of your primer into a plastic cup. Next, use a clean toothpick to apply the primer. I do this by dipping just the tip (2-3 mm) of the toothpick unto the primer. If I get a blob, I wipe it back.



Next, I touch the tip of the toothpick to the center of the chip and allow the paint to flow off of the toothpick into the chip. You will be amazed how well the capillary action works. _If you prefer, you can use the #2 artist’s brush. Do not allow the primer to overflow the sides of the chip.



Allow the primer to dry for 2-3 hours. You can speed dry the primer with a hair dryer after allowing it to air dry for one hour. Simply wave the hair dryer 3-4 inches over the primered chip for 30-40 seconds. Do not touch the chips with your hands, as the oils from your skin will prevent the color coat from adhering.



Now, mix your color-matched paint thoroughly and pour a small amount into a clean plastic cup. As with the primer, use a clean toothpick or #2 artist’s brush to apply the color coat. Touch the toothpick or brush to the center of the chip and allow capillary action to pull the paint into the chip. Apply a small dab at a time and allow it to dry for 2-3 hours. You must repeat this process several times, so don’t try to fill the chip in one pass. Apply several thin layers, and you will get much better results.



The color touch-up process is complete when you have applied enough coats to slightly overfill the chip onto the roughed up area surrounding the chip. Once you’ve filled the chip, allow it to dry for another 24 to 48 hours. The longer the better.



I’m often asked if it’s necessary to apply a clear coat over chip repairs. I don’t think it’s necessary of adds any noticeable difference. If you get the proper touch-up paint from your dealer, it will match without using a clearcoat. However, if you’re a purist in persuit of perfection, substitute a clearcoat for the last 2-3 coats.



Level and Buff _

Until you level or mill the paint repair down to the same plane as the original paint, all you’ll have is an ugly looking blob. This is easily done using the Meguiar’s Unigrit Sanding Block, which helps remove sags, runs and other isolated defects with surgical precision. Don’t forget to soak it over night before use as the directions indicate.



To level your paint chips, use you finger to put a small dab of car shampoo on the chip repair for lubrication. Next, use the Unigrit Sanding Block to mill the high spot off of the chip repair. I always pull the sanding block towards me. Never rub it back and forth or in a circle. When the block dries out, dip it into your bucket of water again. Keep the area well lubricated with water and shampoo. The sanding block will dull the paint. Don’t fear, as your polish will easily restore the luster. When the surface looks level, dry it with a clean towel and inspect with your finger tips. If you can feel a high spot, it needs more work.



The final step is to buff out the repair with a good hand polish. I like to use 3M Perfect-It Rubbing Compound or Eagle One Scratch Remover (a medium grit compound) followed by 3M Perfect-It Swirl Mark Remover or Meguiar’s Hand Polish. Apply the compound or polish to a clean terrycloth towel or applicator pad, rub into the paint area using a short back and forth motion (not in circles), then buff out with a clean terrycloth towel. Tada! The blemish is gone.



<font size="1">Many of the products mentioned in this article are available from Classic Motoring Accessories (http://properautocare.com) and are used at the buyer`s own risk.` Autopia Car Care is not affiliated with and does not represent Classic Motoring Accessories or the manufacturers of the products mentioned.</font>

05-13-2002, 02:30 PM
Ok I plan on tackling 3 small sized paint chips in the hood of the IS300 this weekend. A few comments.

1) Isn`t 1200 grit sanding too rough for final sanding, I have some 2000 & 1500 grit at home.

2)You say to use a hand polish, can I use a PC, or will that rip the paint out, lol.

3)I also heard those touch up pens use factory paint, not laquer paint of whatever that u get from the dealer, therefore metallic paints match better, is this true?



thanks for the great article david.

Bobby G
05-13-2002, 02:41 PM
If you`re doing a large area, I agree that 1200 grit wet and dry is not fine enough. The problem is that by the time you knock down the high spot on the repair, you will be very close to taking off more than half of the clear coat around the repair area. So, if you do a final sanding with 2000 grit paper, you`d be dangerously close to breaking through to the color coat, and then you still have to compound and polish. A good medium compound will remove the 1200 grit scratches with no problem, and you won`t punch through the clear.



Using a PC for compounding and final buff is fine. Don`t over do it with the compound.



All touch-up pens that I`ve used are lacquer, not enamel. That way they dry much faster. I`ve never had a problem matching the color because the paint has a different solvent base than the original paint. In fact, lacquer touch-up has the added benefit of "a little extra bite" into the repair area because of the fast flashing solvent.



db

05-13-2002, 06:39 PM
Ah ok i understand, the paint chips are very small, 2 of them are slightly bigger than a toothpick and one is the quarter of the size of a pencil eraser. 2 more concerns. How many coats is enough, and I think the chip only went to the primer, but how can i tell. It is a grayish color, im assuming that is primer? The site for the urathane based pens is...



http://www.autosharppen.com/benefits.htm



I have the stuff from the dealer, but if you think that gives a better match or better way to apply the paint ill get it. Let me know, thanks.

Bobby G
05-13-2002, 11:14 PM
If you plan to do chip repair often, get yourself a lighted magifying glass so you can see the chip better. If the chip is small, chances are it did not go through the primer. If it did, you will see signs of oxidation pretty fast.



How many coats is enough? When the chip is completely filled you have enough coats. If you do it in one coat, the paint is too thick and you`ll just end up with a blob mess.



I have not used the pen product, so I can`t comment on how it will respond to being wet sanded and polished ("old technology").



db

dahammer
05-30-2002, 12:56 PM
If I may....

I learned this from a guy who once sent a hood back on a spec order vehicle he purchased, because of one tiny spec in the paint.

He refused to have the dealer touch it up `cause it wouldn`t be factory....(they did it) cuz he ordered a new one every year.



Oh yeah .... back to what he taught me..

Use a book of matches to lay in the paint instead of a brush.

Cut the torn off end of the match at a angle ...i.e. a very sharp angle to place a mini spot of paint right where you need it!

shorter angle for bigger chip area can allow you to work it up to the edge of the mishap area.Be ADVISED.... use it sparingly as the tip of the cut will wick the paint & become soggy and therefore make your touch-up sloppy. NO PROBLEM!!!! Cut another & go again.... Lay it up in layers to build it to the existing height of the other paint.





Mike

Bobby G
05-30-2002, 11:04 PM
Mike... I find the best tool is a plastic tooth pick. The capillary action pulls the paint off of the tooth pick into the chip. I know other people who use matches, they swear by it... I still like my tooth picks!

sheltem
03-06-2003, 06:36 PM
I cannot find the unigrid sanding block .. what grit sandpaper can I use instead? :D Thank you.

Bobby G
03-06-2003, 11:45 PM
The grit paper you use depends on the purpose. If you are talking about leveling, start with 1200 or 1500 and finish with 2000. Be sure to use a sanding block.

sheltem
03-06-2003, 11:49 PM
Originally posted by DavidB

The grit paper you use depends on the purpose. If you are talking about leveling, start with 1200 or 1500 and finish with 2000. Be sure to use a sanding block.



Thanks for your reply. Sorry 2 questions.



1) What is a sanding block? Can I just buy the sandpaper at some DIY shops? but a 1500 grit and a 2000 grit?



2) I had problems with the toothpick method... Why does the paint not flow down the toothpick? If I put too much paint then there will be a blob at the end... I am using a wooden toothpick .. :D

jerry@robs
03-07-2003, 02:12 AM
Sanding block is simple a foam or plastic/rubber block where you wrap the sandpaper on to avoid "finger lines"...



As for the toothpick... :nixweiss hard to tell without seeing how you dipped the toothpick into the paint.

sheltem
03-07-2003, 02:43 AM
Errr .. I just put half of the toothpick into a bottle of paint ... is there any other ways to do it?

jerry@robs
03-07-2003, 03:01 AM
You usually dip like a few mm of the toothpick into the paint, not half of the toothpick, just the tip... imagine a sharpened pencil as your toothpick, only the lead of the pencil is exposed, that`s how light you should dip your toothpick into the paint...

sheltem
03-07-2003, 04:28 AM
but the there will be no paint that will flow down into the chip .. wonder if its because my toothpick is made of wood....

sheltem
03-07-2003, 04:59 AM
Oh no .. why did a small white spot appear just beside the spot that I was sanding ... how can I get rid of it? I tried polishing it off but to no avail :(