Unable to buff out scratches

H

Hindsight

New member
Hi all, I just bought a 3 year old car. The owner probably didn't take care of the paint very well because it has a lot of really small scratches on it. The scratches are so small that you can only see them indoors under fluorescent lighting. Outside the paint looks great but when you look at the car under the fluo lights, there are tiny hairline scratches everywhere.



I tried buffing these out with the 7424, a yellow Sonus pad, and 3M Perfect-it II rubbing compound but have had zero luck. I also wet sanded a couple of paint chip repairs I made and after some time with the 7424, the sanding marks are invisible outside under sunlight, but are very visible under fluo lights.



From what I understand, the 3m product I'm using is a very heavy cutting product. This leaves me wondering if the problem is the 7424.... maybe the only way to get these scratches out it with a high speed buffer? I hope that isn't the case and someone here can tell me how to get them out with the 7424.



Thanks in advance for any help!
 
What kind of pad is the Sonus pad? Is it a cutting pad? I'm not familiar with the Sonus color/cutting power designation, but I would recommend to step up to a stronger pad and try it again. Also, I would recommend to work each area longer and see if that helps. What kind of car do you have?
 
Thanks for the quick reply mike. The yellow pad is the most aggressive pad that came with the kit of Sonus pads I ordered.



The car is a 2004 Audi S4, a light-medium blue called Nogaro Blue.
 
Hindsight said:
I also wet sanded a couple of paint chip repairs I made and after some time with the 7424, the sanding marks are invisible outside under sunlight, but are very visible under fluo lights.
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Your a brave man......:grinno:



If what you have done is not acceptable and you want to go to the next step, a rotary would be my weapon of choice.......



Polish it all out with a rotary and finish it off with a PC........



Then top it with what ever you like best........:xyxthumbs
 
gmblack3a said:
Now we understand, the audi clear is rock hard! Its going to take alot of work with a PC.
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Thanks, that makes me feel better! I worked it for what I thought was a long time!



I will try an orange pad... but what is OHC?
 
I believe it's possible, but I can't say that it'll be easy. Audi has notoriously hard clearcoat, and I would definitely take the harshest polish and strongest pad you have on hand and work it slowly. Won't be easy, but I'm sure you'll love the results if done right :) Good luck!
 
Hindsight- Welcome to Autopia!



I've had numerous Audis so I can speak from experience. The PI-II Fine Cut Rubbing Compound is barely aggressive enough to correct Audi clear by PC and it will take many hours. You'd have to use 4" pads, which allow you to apply more pressure. Working with larger pads (I've even tried it with wool) simply doesn't do the job.



IMO you'd be better off with a product like the OHC or Menzerna PG (neither of which I've used) or Hi-Temp Extreme Cut Leveler or 1z Ultra/Extra (both of which I *have* used). Actually you'd be better of with a rotary but it can be done by PC if you put in the time (and it'll be a lot of it). Use a very aggressive product with 4" pads and then follow up with something milder. I'd do one panel at a time and just keep at it until you remove enough clear for things to look OK.



I've removed 2000-2500 grit sanding scratches from Audis by *hand*, but the sanding was done with Meguiar's Unigrit paper (which makes a big difference). I've removed other nasty scratches from Audi clear *by hand* (e.g., fingernail scratches behind door handles), so it *can* be done. IIRC those fingernail scratches (there were only few of them) probably didn't take me a whole hour, but consider that the area involved was only about 1" x 3". You might easily have to put in a few hours per panel.



Last time I did one of our Audis I removed a few RIDS (Random Isolated Deep Scratches) with the PC/4" because I didn't want to risk sling from using the rotary. It worked fine and in one case I quit before attaining perfection for fear of thinning the clear too much. I don't remember how many passes it took, but I'd guess around six-eight with the most aggressive product (3M 05933/Cyclo orange pad) then another two with an intermediate product (3M 05937/Cyclo green pad) then two with a finishing polish (1Z Pro MP/Cyclo white pad). Consider how much work that was...each scratch I was dealing with was maybe an inch long and so fine that most people could never see it (no way you'd see them under fluorescents, I had to use very demanding lighting) and I still needed all those passes.



Oh, and the PI-II RC contains silica, so I hope you're using a good respirator when you polish with it. That stuff can kill you as dead as asbestos can.



Oh#2, if you think it looks bad under fluorescent lights, just wait until you get it under some really demanding lighting ;)
 
I've used the Blackfire SRC (Scratch Resistant Clearcoat) compound and was sucussful at removing my scratches. This product is made specific for some of the harder more resistant clear coats.
 
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