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Discussion Starter #1 (Edited)
I am trying to polish out some road rash (like a fine sand blasted finish) on the passenger side skirt.

When I run my hand over the area it feels smooth not pitted so I think I can get it to look much better than it does now.

With the sticky race tires (track use) the skirt area behind the front wheels take a real beating. :mad:

I used clay to clean it up then a medium polishing compond and it didn't touch it, I don't think a more aggressive compond will touch it either?

What is the next step...............sanding? If so what grit sand paper would I use? I'm not expecting to get it all just as much as I can with out having to repaint it.

Picture of area and the compound I used.
 

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Murry, you might as well try another pass with a coarser compound. I'm a traditionalist so I always use DuPont "red" compound. I like to roll a damp white sock into a ball and then wrap the ball in a white tee shirt. Then, I compound the area _by hand_. :) I know it's old fashioned, but that's how I learned to do it and the red DuPont will seriously cut through surface roughness.

Is the paint clearcoated? If you compound it with red or sand it, you'll most likely cut right through the clear. If you want to sand try a grit above 600.

Forgot this: The best way to compound is with crossing straight strokes (think cross-hatch), one relatively small section of panel at a time. I know lots of instructions say to use a circular motion but, if you use the large rag ball I've described, a back and forth motion makes a lot more sense. You also can keep better control of how the compound is cutting the paint. I learned this from a very traditional body man. It does work well. (Sorry if you already know this.) :)
 

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Murry, you might as well try another pass with a coarser compound. I'm a traditionalist so I always use DuPont "red" compound. I like to roll a damp white sock into a ball and then wrap the ball in a white tee shirt. Then, I compound the area _by hand_. :) I know it's old fashioned, but that's how I learned to do it and the red DuPont will seriously cut through surface roughness.

Is the paint clearcoated? If you compound it with red or sand it, you'll most likely cut right through the clear. If you want to sand try a grit above 600.
Pat and I only wet sanded primer coats after filling with fisheye and under color coats. The only time we wet sanded a top coat was to catch a run, which was very seldom. For some reason the 800 grit sandpaper sticks in my mind for the finest sand; although, we did use a variety of grit as we progressed through the various coats. Use plenty of water to eliminate sand marks or you're back to filling with fisheye again and resanding. I wet sanded barefoot or with go-aheads (whatever you call rubber or plastic disposable beach sandals.)

If you can get most of the road rash off with scrubbing and compound, what is the chance that you could buff the rest out with a rotary sander/waxer so that it would not be as obvious. Of course, depending on how picky you are, you may end up repainting it anyway after trying everything else.
 

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Wet sanding top coats is very trickly. Meguiars sells very fine grits (2000, 2500, and 3000) but even when using them, you may have to follow up with a polish to get the sanding marks out.
 

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Discussion Starter #5
Murry, you might as well try another pass with a coarser compound. I'm a traditionalist so I always use DuPont "red" compound.

DuPont will seriously cut through surface roughness.

Is the paint clearcoated? If you compound it with red or sand it, you'll most likely cut right through the clear. If you want to sand try a grit above 600.
Hi Jim,

The paint is a signal stage to which I have zero experience in wet sanding. I would rather use a courser compond than go too wet sanding. There must be a big difference between a medium cut conpond and Dupont "red"?

I have done some wet sanding on a two stage paint (clear coat) and used 1,000 to 2,000 grit with some success but you could tell the areas I had sanded after a couple of weeks if you caught it at just the right angle.


If you can get most of the road rash off with scrubbing and compound, what is the chance that you could buff the rest out with a rotary sander/waxer so that it would not be as obvious. Of course, depending on how picky you are, you may end up repainting it anyway after trying everything else.
Hi Cheryl,

How have you been. :)

I do have a port a cable buffer and a verity of foam pads which I tried with the medium cutting compond and it didn't touch it.

I need a rotary buffer to get more cutting power but those rotary buffers really belong in the hands of a professional IMO.

The good thing is the road rash is in a spot that is hard to see so it doesn't have to be a perfect job. You have to be on your knees to see it. If I scew up repainting the skirt wouldn't be a big deal but I don't want to go there just want it to look better.




Wet sanding top coats is very trickly. Meguiars sells very fine grits (2000, 2500, and 3000) but even when using them, you may have to follow up with a polish to get the sanding marks out.
Good point I didn't know you could get that fine of grit, if the Dupont Red doesn't work I'll try that next.

But maybe the red compond is harsher then the 3,000 grit sanding paper.............what do you think?
 

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....

Good point I didn't know you could get that fine of grit, if the Dupont Red doesn't work I'll try that next.

But maybe the red compond is harsher then the 3,000 grit sanding paper.............what do you think?
Not sure which is harsher but I think fine grit sandpaper is generally better at leveling out uneven surfaces. If you wrap it around a foam backing pad, it can take the high spots out without affecting the low spots as much as a compound will. It's still a delicate operation though.
 

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IMO, the main purpose of wet sanding is to eliminate orange peel after painting. You would normally lay on more paint knowing that you'll be taking off coats after you wet sand. Wet sanding is then followed up with power buffing with machine grade (fine) compound which takes off more paint - again, the reason for laying the paint on with multiple coats on a repaint. I would not wet sand a factory paint job because a FPJ is microscopic in depth and if not "extreamly" careful, you'll find yourself down to primer or bare metal. Wet sanding is 1000/1200/1500 grit and even finer. Some even finish up with corn starch. :).
 

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But maybe the red compond is harsher then the 3,000 grit sanding paper.............what do you think?

Do not use red compound on a power buffer . Red is for hand application - it's very course. Power buffers take a special machine compound.
 

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Discussion Starter #9 (Edited)
IMO, the main purpose of wet sanding is to eliminate orange peel after painting. You would normally lay on more paint knowing that you'll be taking off coats after you wet sand. Wet sanding is then followed up with power buffing with machine grade (fine) compound which takes off more paint - again, the reason for laying the paint on with multiple coats on a repaint. I would not wet sand a factory paint job because a FPJ is microscopic in depth and if not "extreamly" careful, you'll find yourself down to primer or bare metal. Wet sanding is 1000/1200/1500 grit and even finer. Some even finish up with corn starch. :).
Thanks so much for your 2 cents lowmileage,

I have been looking closer at my road gravel blasted skirts and been thinking about just going up 1 level from a medium cutting compound (applied and taken off by hand) and calling it good.

The skirts are very easy to remove so maybe I'll just plan on taking them off next winter (2009) to have them repainted? This is the price I pay for driving around on the track and streets with sticky race tires.

I now have a set of deducated track wheels so I can switch to the wheels with the street tires when I'm off the track.
 

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...I now have a set of deducated track wheels so I can switch to the wheels with the street tires when I'm off the track.
... and with this decision, "msiert" finally showed the BB that he was serious about his upgrades... :D:D:D

Don't sweat, Murray. It's much more enjoyable to not worry too much about this stuff, and and not too costly to have your rockers painted from time to time. Consider a 3M layer of vinyl protection next time you get them re-done. :)

Best regards,
 

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Another suggestion

You could move in an opposite direction. Perhaps you could get good reults using one of the "fill in glazes" on the market. Meguiars had a good one, although I haven't see it in the parts stores for awhile. The fill in glazes are intended to fill small imperfectiions in the paint, hence the name. :) They work pretty good, especially when covered with a good wax. A slighltly more agressive approach is to use one of the scratch removers like "ScratchX". These basically work the same way i.e., they fill in surface scratches (more or less). Neither product removes paint; they are intended to just hide the imperfection for awhile.
 

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Discussion Starter #12 (Edited)
Don't sweat, Murray. It's much more enjoyable to not worry too much about this stuff, and and not too costly to have your rockers painted from time to time. Consider a 3M layer of vinyl protection next time you get them re-done. :)

Hi Enrique,

Ya, your right I don't want it to be a hanger queen and never drive it.


You could move in an opposite direction. Perhaps you could get good reults using one of the "fill in glazes" on the market. They work pretty good, especially when covered with a good wax.

A slighltly more agressive approach is to use one of the scratch removers like "ScratchX".

These basically work the same way i.e., they fill in surface scratches (more or less). Neither product removes paint; they are intended to just hide the imperfection for awhile.



Not a bad idea for a pitted finish.
 

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Discussion Starter #13 (Edited)
Went to the detail supply store today and asked them what would be the next step up (better cutting) from their medium compound and they recommended the following compound along with a specific foam pad to use with it.

Here is the products and the before and after pictures............I'm calling it good.

The after pictures were taken right after using the compound (without any waxing)
 

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Discussion Starter #14 (Edited)
Here are some pic's showing the rear bumper return into the wheel well and I had to take a couple of shots of the suspension,
 

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My technique FWIW

I have a GTV with very soft (read el cheapo) red paint ; no clear coat. Here in San diego we get severe water spots (hardened calcium) and if given the opportunity (ie standing water left for a while on the soft paint) it will drive moisture into the finish, much like a hot plate on a lacquered table top.

I use 1500, 2000, 2500 with DI water wet sand until stain is gone,, then finish with 3M medium polish, followed by "finish it" 3M very fine polish liquid.

I run all this on a 35 year old Craftsman circular buffer with lambswool bonnets (one for each grade of polish). Very, very light on the touch.

Final coat is Zaino Bros wax. It looks great for about a year or until my kid purts his sweaty hockey gear on the trunk for the night, then start all over again!
 

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Here is the products and the before and after pictures............I'm calling it good.

I think it looks pretty doggone good, Murry. :) Better by far than what you started with. Fer' grins you might try a fill in glaze before you do a final wax and see how that works.
 

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Discussion Starter #17
I have a GTV with very soft (read el cheapo) red paint ; no clear coat.

I use 1500, 2000, 2500 with DI water wet sand until stain is gone,, then finish with 3M medium polish, followed by "finish it" 3M very fine polish liquid.

I run all this on a 35 year old Craftsman circular buffer with lambswool bonnets (one for each grade of polish). Very, very light on the touch.

Final coat is Zaino Bros wax. !
Hi goats,

My Spider has a signal stage paint finish too (no clear coat). I don't know for sure but I think this type of paint finish is easier to take out small inperfections sence you don't have to worry about burning through the clear coat?

I have always described my paint finish as soft too (very easy to scratch or stain).

I might have to try your paint repair method the next time but would I have to have a circular buffer?



I think it looks pretty doggone good, Murry. :) Better by far than what you started with. Fer' grins you might try a fill in glaze before you do a final wax and see how that works.
Thanks Jim
 
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