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Jehu
08-26-2006, 08:34 PM
In too much of a hurry i used a semi circular driveway to turn about which was on too steep of an angle and i scraped the bottom edge of the bumper all the way across. Its just visible when approaching the car from the back. It so happened that the person who's house i was looking for , to which i was heading when i U-turned in that driveway owned a '71, i think he said, BMW 2002 with a front lip spoiler. He told me when i mentioned my unfortunate asphalt scrape that 400 grit sandpaper lightly by hand would get it smooth and then just the correct touch up paint would make it good as new. Is this about right?

Robke
08-26-2006, 08:52 PM
hard to make out , show a pic of the damage

Jehu
08-26-2006, 08:57 PM
hard to make out , show a pic of the damage

its dark here now so i'lll snap one tomorrow.its thru the paint to the bottom coat.

632 Regal
08-26-2006, 09:13 PM
esplain better.

Jehu
08-26-2006, 10:32 PM
all along the bottom of the ABS rear body part( not the bumper actually) that plastic. I used a paint brush in Photoshop to convey the general idea. Its not as dramatic as illustrated but its is visible.

http://img207.imageshack.us/img207/5802/scrapessv2.png

Gayle
08-26-2006, 10:40 PM
I would hit it with a fine grade rubbing compound first. Rubbing compound makes lots of evils fade away if you don't go nuts with it.

Jehu
08-26-2006, 10:46 PM
I would hit it with a fine grade rubbing compound first. Rubbing compound makes lots of evils fade away if you don't go nuts with it.
There are a few fairly deep gouges.The guy who reccoed the 400 grit sand paper pointed to hit front lip spoiler showing me how smooth it was and said he scraped it like i did all the time and was really smooth but if it was fiberglass might it be a different story?

Gayle
08-26-2006, 11:07 PM
When I talked to the guy at the indy about my paint chips, he suggested building up the paint with repeated applications of touch up paint using an artist's brush and doing wet sanding in between. I didn't know what wet sanding was and here is what our fellow forum members told me about the technique.

How do you wet sand? Is it a good idea? (http://www.bimmer.info/forum/showthread.php?t=24624)

If you have gouges, this might work.

Jehu
08-26-2006, 11:11 PM
So the fact that this is plastic makes no difference? I'd tend to think paint would be harder to build up on plastic.. but I'm no chemical engineer.

Gayle
08-26-2006, 11:24 PM
So the fact that this is plastic makes no difference? I'd tend to think paint would be harder to build up on plastic.. but I'm no chemical engineer.

Don't really know about the plastic. If the gouges are deep, what options do you have? Do you want to sand that much? It would seem like sanding enough to get out deep gouges would leave wide stripes needing touch up.

Don't blow off the rubbing compound suggestion too quickly. When hubby had the 525 he did something that left a lot of scrapes and some blue paint in that area. It was white so it really showed. Rubbing compound really did smooth out all but the deepest of the gouges. After working on it about 3 times, it really didn't show.

Jehu
08-26-2006, 11:26 PM
well i'll try your ideas Gayle.Nothing to lose, Thank you..

aston_jag_tech
08-27-2006, 12:00 AM
Awww man, sorry to hear about the damage to the bumper. By thw way did you ever figure out the bushing work for your front susp.?

Jehu
08-27-2006, 12:13 AM
Awww man, sorry to hear about the damage to the bumper. By thw way did you ever figure out the bushing work for your front susp.?

I made an appointment with a local BMW specialist three weeks ago. In that time i found BMA selling Lemforder arms w/ sachs/Boge 750i bushings for $200+shipping. I figured this Indy would do me righteous so just took it in. He called me later that afternoon and said yes the Upper trust arm bushings and arms needed to be replaced and the quote was $750.00 parts and labor.After i the initial toxic shock feeling subsided and after asking where he'd getting the parts and explain i found the OEM parts on line for $200 he just said do you want me to do it ? I said do it. I wanted the car fixed. I'd waited three weeks and if i said no and took the car back I'd have to wait another three weeks all to save about $300.00 I wanted to be able to drive the car . I'm still kind of nauseous about it but the braking shudder is gone.

Robke
08-27-2006, 04:13 AM
Normaly a scratch in ABS wil also push some material up wich you can feel by touching the scratch from the side, if so you have to sand it flat first (use 400 grid wet paper with a small sandblok or a small wooden block to keep it on top of the scratch , take youre time here!)

i would go with the touch-up method, it does'nt realy mather if thats on metal or plastic, after rubbing/sanding make shure you degrease very good and build it up in thin layers with a fine brush , after all the layers are aplyed you can flatten it first with a bit af 1200 grid of wet sandpaper (just to get the top flat, not more and use lots of water) and after that use a rubbing compound to clean it up and your done.

after filling the scratches with paint leave in drying for a good time, a couple of days should be fine ad wait a half an hour to an hour between the layers of paint so it can dry realy good.

good luck

skr
08-27-2006, 06:40 AM
i had some deeper scratches than you from an idiot friend backing up into a tall sidewalk :) did mine with epoxy and duplicolor matte black paint(spray can). can't see a thing. i sanded it with 400, filled the holes and scratches with epoxy, let it dry, sand it with 600, then 1200. after that 2 thin layers of paint. it matches the plastic perfectly. there was a nice writeup with pics showing this same method on the bumper trim... hope this helps

aston_jag_tech
08-27-2006, 01:56 PM
jehu,
Sounds like they took care of you. Now all you have to do is deal with that bumper. I give you respect for how your car is, looks very straight, clean, and with a very nice paint job with rims.