Prep sanding: What grit?

Discussion in '2.3L (N/A & Turbo)' started by freakintiger, Jul 6, 2004.

  1. freakintiger New Member

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    I'm going to be sanding down my car soon(hopefully), I'm wondering if anyone knows what grit paper to start with, then what paper to use next and so on.
    I did this professionally about 10 years ago, but I can't remember the grades of sandpaper used.
    Thanks!
  2. mr_woodster New Member

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    depends on if your scuffing for a repaint or taking it down to the metal. We used anything from 60grit/80grit on an orb or a D/A grinder to get to the metal, then 120-150 for taking the clear off. This is all from a year or so ago...so im doing my best to *remember*
  3. freakintiger New Member

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    Just scuffing for a repaint, sorry I should have specified.
  4. Stinger Founding Member

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    I'd go with 400 or finer for the final sand before you spray it...even 400 normally shows through a bit.
  5. SVO1 Lord of The somethin' somethin' somethin', hell, I

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    I agree with Stinger, and obviously make sure you feather out any chips/scratches, and use a good primer surfacer.
  6. GTPhreak Founding Member

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    scuffing for repaint? if the paint is in good shape you can probably get away with scotchbrite...i would probably use a DA sander with 400 then 600 though
  7. Lex Founding Member

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    Hey I'm glad this topic came up since I asked a similar question. Ok I need to do some body work, and I too like to know, what grit to start and finish, ALSO after I prime paint, DO i need to sand that and if so what grit, then base coat, do I need to sand that too. And finally Clear coat. I heard your not suppose to sand clear coat. I have matching paint of my red LX, factory color. I done this in the spring and it came out OK but it doesn't have the original shine and gloss. I need advice. Thanks
  8. JamesBaumann New Member

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    Here's what I did to mine and it worked it pretty well.

    - Sand off existing paint (40 grit)
    - Sand again to scuff off the last little bits of primer (150-180 grit)
    - Sand once more to smooth out surface before applying primer (300-400 grit)
    - Apply Primer (I sanded this once and it didn't turn out as well as when I didn't)
    - Apply Basecoat
    - Apply Clearcoat
    - Sand Clearcoat until it has absolutely no more shine what so ever (400 grit)
    - With a lamb's wool buffing pad and an electric drill I buffed out the clearcoat again and again and once more (a lot of buffing) This made it very smooth to the touch and made it shine better than it had before I sanded the clear.
    - Find a good Caranuba wax and wax it as many times as you please. The magic number seems to be 6.

    If you want to clear it more than once then you should repeat this sand/buff process after every second coat of clear. This advice was given to me by my neighbour who did this professionally for many years. I just did the fender of mine with touch-up paints from my local auto parts store. It was black and I was actually pretty happy with the results with the exception of my own personal un-related to this procedure mistakes. One of the bigger problems that I ran into was sanding all the way through the clear and paint right down to the primer. This was basically just because it was my first time and I was using cheap paint. My recommendation to fix this problem it to spend more time sanding with a higher grit paper than less time sanding with a slightly lower grit, the results will be worth it in the end. Another recommendation is too put on more coats of paint than of primer so you won't sand all the way through the paint and get a different coloured finish. I did two coats of each and this is what happened. I think next time I do it I'll use two coats of a thin primer, 3-4 coats of paint and however much clear money will allow. I'd like to do up to 4-5 coats. Clearcoating is also something that you can do anytime. As long as you have a few coats on to begin with then you can add more coats on later. Who knows, I might have 10 on there by the time I am done. Well, this is my experience and hopefully one of you out there will be able to learn from it, I hope my advice helps somebody out there who is in search of this info.

    By the way, here is a link to an autobody only site with forums, how to articles and e-books.

    www.autobody101.com

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