Advice needed re. hood scratches

Apr 22, 2005 12 Replies

I could use some advice on what to do about this: this morning, a large piece of what I think was rubber was kicked up by the car in front and bounced off the hood of my E46 (colour titan silver).



I haven't had a chance to examine it in detail, but it looks like this left two 20 mm-long (1/2 inch) and 1 mm-wide gashes in the clear coat. (AT least I hope that's ALL there is.) Being on the driver's side the marks are going to be quite visible while driving in direct sunlight as two white gouges.



I could use some advice on how to proceed with this, as I don't know if there are any easy fixes for this. Being two fairly wide shallow scratches is it necessary to have the area professionally repaired by the dealer?



I'm sure the dealer would first try to polish out the scratch by 'sanding' down the paint, which I'd rather NOT do unless absolutely necessary. OR is it possible to use some other clear-coat-polish-type substance (one that'll actually last)?



Some folks recommend the fingernail test. If the scratch is deep enough to catch a fingernail lightly dragged across at right angles, it's too deep to polish out. If the damage doesn't extend into the color coat, you may get "like new" results with light sanding and a couple coats of clear.

You can first try polishing it out, using a cutting compound Like Farecla. Provided the clear coat hasn't been penetrated this will work well. Do a bit at a time and then polish with a clean cloth. It should be obvious if it's going to work.

Not without removing the scratch first, IMHO.

Thanks for the replies. I've now had a better chance to examine the damage. There are three scratches - they are very shallow (~1/2mm) but quite wide (~1mm). The clear coat is roughed by by the scraping action, so they shine a bright white. I don't think just polishing will hide them completely. Sad, as the paint is in otherwise immaculate condition. = (

To completely & permanently fix this, I expect they would need to be 're-filled' with clear-coat. I really do not know what this would involve...?

At a minimum, I suppose this would involve completely sanding down the area + re-applying the clear coat (i.e. a bigger and expensive job).

I'm still not sure what to do about this. One of you must surely have had similar damage repaired at one time or another - what would you recommend?

You would be amazed at what a good detailer can do with a buffer. Clear coat is generally 3 to 6 mil's (thousandths of an inch) thick. If the scratch isn't into the color, a good detailer can remove it. The operative word is "good" There is a fine line between using a buffer to heat up and move the clear and burning it.

Where are you located?

I'm currently located in Europe. I have an excellent dealership here, so I'd probably let them handle it (perhaps they use an external body shop). I don't think I'd entrust it to just any old body shop over here.

Having said that, the scratches are about 1/2 to 1mm deep (0.5 millimeter = 0.0196850394 inches according to Google). Hard to tell exactly - like I said, they're shallow but quite broad. For that reason I'd be worried about them having to take some pretty extreme (and expensive) measures, potentially making the situation worse (read: even more noticeable).

I have an idea... bring it to a few body shops and ask for an estimate of repair. They are generally free and you are under no obligation. Asking for their expert advice would seem the best course of action.

-Fred W

Check this site for ideas:

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There's no need to use a buffer - in any case a decent one is extremely expensive. Elbow grease and a decent cutting compound will do *exactly* the same thing. Without the risk of heat damage.

Get some Farecla G3 and a roll of stockingett - cotton polishing cloth.

Make sure the area is perfectly clean.

Damp the cloth and polish with a circular motion. Use a clean cloth to buff up often to check progress. If you actually go through the topcoat before removing the scratch - seen by the colour appearing on the cloth - nothing is lost as the repair shop would have to do exactly the same. All you'd have lost is the small cost of the materials and your labour.

Ask a local BMW dealer who they use for minor body repair. The pre-owned guys will know. I've seen them working at my dealer (it's a mobile thing), and I was VERY impressed with the quality of the work. They are specialists in exactly what you need - professionally fixing a little blemish on an otherwise perfect finish.

Again, thanks for the advice, I've taken it all on board.

I can see your point about trying to polish it out using a cutting compound - that should give good results. Though, not having worked on such things before, I'd be worried about actually doing more damage than good. Using something that actually sands down the paint is probably best left to someone with experience (i.e. not me). (Though if the car were older, I'd likely give it a shot.)

The next time I'm at the dealership, I'll ask them what/who they'd recommend. Until then, I'll just have to live with it. Bound to happen again - what with the amount of debris flying around the roads. =(

Don't ya hate it when this happens? I was driving down the freeway about 18 months ago when a car threw up some debris off the road and it smashed and skipped across my hood. Some of it also bounced off my windshield, and how it didn't break or crack, I'll never know, considering how fragile my windshield apparently is. In my case, the crap off the road actually did some real damage (but small area) to the front right side of my hood, then left small, short, but deep gouges farther back, just in front of where my wife was sitting. I'm just thankful it didn't come in the car and whack her in the face. Anyway, I had to have my entire hood refinished professionally. This cost me I think about $750, I don't remember exactly.

But if *I* were you, I'd go to a good, professional shop for this. It couldn't be *that* expensive to fix.

-- Cliff

You can't by hand. Provided you clean the surface first and only use clean cloth. It's a pretty slow process.

Sanding down is simply a faster way of removing the paint. To remove a scratch you have to level *down* the surrounding paint. And only obviously works if it's thick enough.

I'd personally use 1200 grit wet or dry used wet to sand the area smooth then cutting compound to restore the shine, but for a novice it's safer just to use the cutting compound. It will take longer and is more work, but the chances of doing more damage than already exists small.

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