Another tip ive learned is to put a few drops of dishwashing soap into a 5
gal bucket and use a 32 oz plastic soda cup to pour it over the surface as
you sand. Your paper will never clog and you will use less arm pressure and
have strength to do something else at the end of the day. (Allan, read it as
you may). This also allows you to use a finer grit sandpaper e.g.1500, 2000.
The finer grits are great because you have less chance of cutting through
the paint. I would only go down to 1000 for a run. If you do get a run, I
use a technique that I will call for lack of a better word "painting" it
out. As I paint the car, I will go back to that run and put an extra spray
over that area in between total coats. The car may have 3-5 coats, but that
run will have 6-8 coats. This tends to "dilute" the run and allow it to
flatten out a little more. The side benfit is tha when you sand the car,
there is enough paint to keep you from sanding through. Just leave enough
time for the solvent to escape or you will have little bubbles and pinholes
in the topcoat.
If this is a first color sand, STICK TO THE FINE GRITS and CHECK YOUR
PROGRESS OFTEN. So it takes you 3 days instead of 3 hours. Since profit is
not your goal, it is easier for you in the long run. Follow Craigs advice.
It is sound!
>Kevin,
>
>I decided to post this since it may be of interest to the
>general list. If you pay someone to wash your car you can ignore
>this.
>
>Kevin Meek wrote:
>
>> I just painted our Alpine in using PPG Concept single stage
>> urethane. Although I painted it in the garage, I still got
>> a fair amount of dirt in the finish. I've painted several
>> cars, but have never been brave enough to color sand once
>> the final coat goes on. Do you have any advice or perhaps
>> you could point me towards a reference on how to color sand
>> and polish this finish properly...thanks!
>> ............................................................
>> Kevin Meek (kevnmeek@netcom.com) Sunbeam Tiger Mk 1A
>> Santa Cruz, California Sunbeam Alpine S3 GT
>
>Talk to your supplier of the paint about dry time. If you didn't
>add a hardener you may have to wait 6-8 weeks before polishing.
>If it is metallic, sanding through layers can often cause
>visible blemish's. It would be helpful to visit your local book
>store and thumb through some "How To" books on refinishing, or
>go to amazon.com, they have several. I have a good one at home
>that I will try to find, and give you the name.
>
>In general here are some of the "tricks" that I have learned
>(Sometimes the hard way!). This one reason why good paint jobs
>are expensive.
>
>1. Never use your bare hand on the sand paper.
>
>2. The body supply shop should have neoprene sanding pads that
>can be used on curved surfaces, like the tops of fenders. The
>sides, doors, hood, and trunk should be sanded with with a
>harder rubber block. These are usually flat on one side and
>curved on the othr and about 2.5x4 inches.
>
>3. Use 1200 or 1500 sandpaper. 1500 is safer, because it cuts
>slower and requires less polishing.
>
>4. Use lots of clean water. If you use a bucket, change it
>often. A dribbling hose works well to keep the surface wet.
>Clean the sandpaper regularly by rinsing in clean water and
>lightly rubbing it with you hand.
>
>5. When sanding the pressure will vary. You can use moderate
>pressure with the hard block on flat surface, but as soon as the
>surface starts to curve, ease up up on the pressure and CHECK
>YOUR WORK OFTEN. Remember, it is pressure between the sandpaper
>and the paint that does the work, not force. So, as the area
>being sanded is reduced you must reduce the force being applied.
>This applies to moderate curves as well, since the crown of the
>curve will bear most of the force. Go slow until you get the
>hang of it.
>
>6. Checking your work. If you want a mirror like surface with no
>orange peel, use a squeegee to check progress. Use a small 1/8
>thick hard rubber pad, with a straight edge for a squeegee.
>These are used to apply spot putty and are available at the
>paint supply store. After sanding a few strokes, use the
>squeegee to dry the area, like you would on a window. The sanded
>paint will appear dull, and the remaining orange peel
>depressions will stand out as shinny spots. Sand a few more
>strokes and recheck. You want a smooth uniformly dull surface.
>Use judgment, if a flaw is too deep, don't try to remove it
>completely, you may sand through the surrounding paint. Stop as
>soon as a uniform surface is achieved. Don't try for perfection.
>You would rather have a little peel in a few spots than no
>paint.
>
>7. Sand parallel to edges and creases, NEVER ACROSS ONE. I wrap
>a finger around the block and use the edge or crease to guide my
>finger in order to maintain the sanding block about an 1/8 inch
>distance from the edge. If it is important to you finish the
>last 1/8", do it very carefully by itself. Work closer to the
>edge but never on it. USE VERY LIGHT PRESSURE. CHECK YOU WORK
>OFTEN.
>
>Polishing
>
>1. The large flat surfaces can be machine polished. Meguiar's
>products are good, available and come with a pamphlet that
>describes the process.
>
>2. Two steps is usually sufficient for a non-show car. The first
>step is a polish and the second is a swirl removal, or fine
>polish.
>
>3. Tape the edges of the panel you are going to polish with 1/4"
>masking tape. Wrap the tape around the edge. Don't forget the
>adjacent edges, ie: if you are polishing a door, tape the door
>edges and the adjacent fender edges. This will prevent burning
>the paint on the edge with the buffer.
>
>4. Use a low speed (1000 rpm) buffer. Either a foam pad or wool
>pad will work. If you use wool you have to keep it from getting
>clogged. The body shop supply store has a simple tool that
>unclogs the pad.
>
>5. Keep one pad for initial polish and a separate one for final
>polish.
>
>6. Keep the pad flat and use light pressure.
>
>7. Apply the compound to the paint and spread with the buffing
>wheel. Buff a 2 square foot section at a time. Keep the wheel
>moving back and forth over the surface using a light pressure.
>Buff until the compound dries and the shin starts to come
>through. Then wipe with a clean cheese cloth or soft terry cloth
>towel. Repeat if necessary.
>
>8. When approaching and edge, hold the buffer such that the
>surface of the pad is moving from the panel toward the edge.
>Don't allow it to move from the edge toward the panel. If you
>slip up occasionally the tape will save you, because you will
>have to burn through the tape before getting to the paint and
>you will see the damage on the tape.
>
>9. After finishing the panel repeat with the finer polish.
>
>10. Repeat this until the entire car is done. (You could do all
>the initial buffing and then change to the final.)
>
>11. Remove the tape from the edges and polish up to the edge by
>hand. This is the only time I don't use a block. You need to
>polish using strokes parallel to the edge, using a clean cheese
>cloth or soft terry cloth towel. Use you finger tips and press
>lightly. Don't go over the edge.
>
>12. Wax using Meguiar's Cleaner wax, and use Meguiar's Detail
>cleaner between waxes. If the car is kept in a garage and
>cleaned with the detailer you'll never have to use water.
>
>Good luck!
>
>Craig Wright
>
>
>
>
>--
>**********************************************************************
>
>Craig Wright Product Design Group, Inc.
>craig@p-d-g.com 4635 Viewridge Ave.
>(619) 569-3484 x309 San Diego, CA 92123
>fax: (619) 569-3490 http://www.p-d-g.com
>**********************************************************************
>
>
>
>
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