How to fix previously(poorly) repaired scratches

[joshhas99problems]

Had a regular client bring an Estoril Blue BMW m3 sedan by for polishing and to try and improve the appearance of a few big scratches on the driver door.

Somebody used touch up paint previously although the only real sign of this is the smearing running the length of the scratches.

So my question is how do I remove the previously applied touch up and then what's the best method of dealing with the scratches? I have limited touch up paint experience but lots of patience haha

Thanks!

Josh7247372474

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[2black1s]

Those scratches look pretty wide. Or is that just the excess paint smeared around the scratch?

In any case, the paint used for touch-ups is typically lacquer and if that is your case, then lacquer thinner can be used to remove it. Try on a small section near the end of one of the scratches. Saturate a cotton swap with lacquer thinner and see if it will remove the touch-up paint. Depending how long the touch-up has been there this may take some time. The lacquer thinner will not instantly dissolve the paint but it should eventually. If you can see the color on the swab after a little rubbing then you are making progress. The original finish should tolerate the lacquer thinner for a certain period, but do pay close attention and stop if it appears to be softening.

If that doesn't work then you'll need to resort to mechanical removal, and that can be a risky proposition... Probably something that should not attempted without careful consideration of the consequences. Some things just can't be fixed.

If you are successful at removing the old paint, then you can repeat the touch-up using care to keep the touch-up paint within the confines of the existing scratch. Even at that, the color looks like a light metallic blue, and if that is the case do not expect a perfect color match... It isn't happening.

As for how to perform the touch-up, here's how I do it... https://www.autogeekonline.net/forum/how-to-articles/125096-discerning-paint-chip-touch-up-not-everyone-every-chip.html?highlight=discerning ... Although written for touching up chips, the same methodology can be used for scratches.

There are simpler ways to do the touch-up, but I don't think there is any better way.

[joshhas99problems]

Those scratches look pretty wide. Or is that just the excess paint smeared around the scratch?

In any case, the paint used for touch-ups is typically lacquer and if that is your case, then lacquer thinner can be used to remove it. Try on a small section near the end of one of the scratches. Saturate a cotton swap with lacquer thinner and see if it will remove the touch-up paint. Depending how long the touch-up has been there this may take some time. The lacquer thinner will not instantly dissolve the paint but it should eventually. If you can see the color on the swab after a little rubbing then you are making progress. The original finish should tolerate the lacquer thinner for a certain period, but do pay close attention and stop if it appears to be softening.

If that doesn't work then you'll need to resort to mechanical removal, and that can be a risky proposition... Probably something that should not attempted without careful consideration of the consequences. Some things just can't be fixed.

If you are successful at removing the old paint, then you can repeat the touch-up using care to keep the touch-up paint within the confines of the existing scratch. Even at that, the color looks like a light metallic blue, and if that is the case do not expect a perfect color match... It isn't happening.

As for how to perform the touch-up, here's how I do it... https://www.autogeekonline.net/forum/how-to-articles/125096-discerning-paint-chip-touch-up-not-everyone-every-chip.html?highlight=discerning ... Although written for touching up chips, the same methodology can be used for scratches.

There are simpler ways to do the touch-up, but I don't think there is any better way.Thank you so much! That's the oversmear the scratch in a tiny little guy roughly in the center of the smear marks. I will give the laquer thinner and cotton swap method a try!

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[2black1s]

Thank you so much! That's the oversmear the scratch in a tiny little guy roughly in the center of the smear marks. I will give the laquer thinner and cotton swap method a try!

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Anytime! I like helping others when and where I can.

Be sure to follow up here so we know how it works out for you.

And one more thing... You can also try acetone in lieu of lacquer thinner. It will do the same thing except maybe faster depending on the grade of lacquer thinner you're using. Acetone is a little more universally consistent than lacquer thinners.

[RTexasF]

I have limited touch up paint experience but lots of patience haha

I would have declined. If you make it worse guess who is going to pay for the repair? Really risky undertaking.

[joshhas99problems]

I would have declined. If you make it worse guess who is going to pay for the repair? Really risky undertaking.Agreed and I likely would have if I didnt have a good relationship with this client and have known him for years.

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[joshhas99problems]

Anytime! I like helping others when and where I can.

Be sure to follow up here so we know how it works out for you.

And one more thing... You can also try acetone in lieu of lacquer thinner. It will do the same thing except maybe faster depending on the grade of lacquer thinner you're using. Acetone is a little more universally consistent than lacquer thinners.Well the laquer thinner works. Took some experimentation but looks like at the very least I will get those nasty smears off!7248972490

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[2black1s]

Well the laquer thinner works. Took some experimentation but looks like at the very least I will get those nasty smears off!

Good to hear. Glad my suggestion actually helped out. Looks 100x better in your pics.

[joshhas99problems]

I didnt attempt touching it up after removing the old touch up paint, just polished it out with Menzerna 400 like the rest of the car and all 3 scratches are hardly noticeable. Customer is super happy!72615

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[joshhas99problems]

One more72616

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[2black1s]

Great job... Especially considering this was a first attempt at something outside of your wheelhouse of experience.

To quote Jimi Hendrix - "Are You Experienced?"

Now you are, and you have another tool in your toolbox.

Just keep this in mind - this method will only work if the touch-up was done with lacquer. The good news is that lacquer is the most common touch up paint.

And just to add another point that I've learned over the years... Whenever you are doing a repair such as this scratch repair, your first objective should always be to keep the repaired area as small as possible. What I mean by that is if the scratch is 1/32" wide when you start, then ideally, your repair will be 1/32" wide when completed.

Your example illustrates that point perfectly. The original repair was much larger than the original defect and it stuck out like a sore thumb. It may have even looked worse than the original scratch. Your rework of the original repair to reduce its size to that of the original defect, even without adding any additional touch-up paint, results in a much less noticeable repair.

That is why I emphasize "staying within the margins" of the chip (or scratch) in my touch-up method linked earlier.

Thanks for following up with your results.