Oh boy.. What did I do wrong?

P

Parmesan

New member
I have some scratches on my rear bumper I am in the process of fixing. In my kit from Paintscrach.com were some sandpapers - 250, 600, and 1000 grit. Per the online instructions from paintscratch, I proceed to use the Primer paint pen on the black areas and then they wanted me to use 250 and then the 600-grit papers to smooth out the primered surface to get ready for paint. Well, I felt the 250-grit and said NO WAY and proceed to just use the 600-grit paper and wetsanded the areas.. What you see below is what happened to my paint. Look at all those white scratches!! :nervous2: :nervous2:



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I let everything dry and used the supplied Rubbing compound to try and get out the marring I left behind. It got out some but it my car pretty much looks likes the pictures still.. I then tried ScratchX and that didn't help. :(



Is my paint ruined now?? What can I do to fix the marring? :help: :help:
 
It looks fixable, but you'll need to machine polish with an aggressive polish and several passes, then use a finer polish to remove the hazing.



Do you have a PC? If you do I'd suggest using a 4" yellow spot pad...it'll do rotary style corrections without the danger..



Something like Menzerna Power Gloss, 1Z Extra, SSR3 provided you haven't gone through the clearcoat.



For paint chip/scratch repair there's only one choice in my books: http://www.langka.com/



Nothing else matters. :up
 
I dont think it is too far gone.



A couple things though.



Metallic paint should not be wetsanded. It will dull the flakes and buffing them will not restore their flake-y-ness.



You will need to dab on some clear coat, that is what you will need to wetsand.



When fixing a scratch like yours, you need to build up the layers of paint until they are above the height of the paint on the car. This way, when you wetsand, you will be lowering the clear(that is ontop of the color touch up paint) to the level of the factory paint.



I would use a sanding block on an area as large as that.



Soak the wetsand paper in water for an hour or so before you start.



I wouldnt touch anything like that with 600 grit paper.



I would start out with 1000 or 1200, and after the touch up is down to the factory paint, switch over to 2000, even 3000 if you can find it.
 
Parmesan said:
...Is my paint ruined now?? What can I do to fix the marring?
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I dunno, maybe you did irreparable damage :( What your pics show is a good example of "wetsanding gone wrong". That sandpaper was so coarse that the only way to use it would be to keep it completely off the "good" paint and only touch the primer with it. And I wouldn't have used it at all. For that matter, I wouldn't use the 1000 grit at all either. With something that coarse, you can often only do *one* stroke at a time- stroke, inspect, repeat.



Short of using more of the rubbing compound, or a different compound with a rotary, I honestly don't know what you oughta do. Maybe get some 3000 grit paper to take out the worst of the marring and *then* use the RC, followed by lots of work with the Scratch-X. But you're taking off a lot of clear and I can't be too optimistic. Sorry I can't give you better news, but you might be looking at having a (very good) paint shop do a spot repair. I guess there's no real harm in trying more hand polishing, but I'd consider getting the 3,000 grit paper (Meguiar's is great quality).



Oh, and if you do get the finer sandpaper, soak it in car wash soap for added lubrication and go *very* easy. Maybe the "one stroke" approach, even with the finer paper.
 
600 GRIT WILL NEVER COMPOND OUT. 600 grit is before you lay the base coat down. the max rubing compound will take out is 1000 grit if you are lucky. Stick with above 1200 grit for wetsanding.

Also, this will have to be reshot and blended in to make it look right.

No polish or compound can fix this
 
yea, sucks when you use the wrong paper!



I did go forward and apply touch up paint to my black areas, enough so that it did build above the other paint.. Do you recommend I apply my Clearcoat pen to the build up now or should I wetsand the touch up areas and level it out and THEN apply the clear?



Secondly, for those spots that got damaged, do you think applying clearcoat to it will help at all? I will definitely try some more "muscle" on the areas with Scratch-X after my touch-up session is done.
 
Parmesan said:
I did go forward and apply touch up paint to my black areas, enough so that it did build above the other paint.. Do you recommend I apply my Clearcoat pen to the build up now or should I wetsand the touch up areas and level it out and THEN apply the clear?
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If your color is above the other paint you need to get it down below the other paint. Then add clear until it's higher again. Then wetsand/compound/etc. When it's all done you want the color, then the clear, with the clear level with the surrounding, original paint.



Secondly, for those spots that got damaged, do you think applying clearcoat to it will help at all?
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No, sorry, that won't work.



Touching up paint can be a lot trickier than one might think, especially with metallics.
 
WET SANDING WITH 250, 600 or 1000 GRIT ... OH DEAR GOD. Those types of grades are meant for primer type of work! Never on a painted automotive surface. 1000 is borderline being to way to aggressive for an consumate professional with a tonne of experience.



Personally, I'd only wet sand with 2000+ unigrit type paper. Depending on what I was trying to achieve, I'd go 2,500 or 3000 only!



Here's what I would do:



1. Pull out the Diamond Cut on a rotary with a wool pad and do an initial buff out and see what the real damage is.



2. Then, either wet sand with 2,000 grit paper to level out some of the less deep scratches and then go back and use DC with a wool pad to remove the sanding marks.



3. Go at with a cutting pad and DACP on a rotary.



4. Go at Speed Glaze on a DA with a polishing pad.



5. Top off with like 100+ coat of Z2Pro. Kidding, but definitely use a sealant with several coats as that part of the clear is almost definitely compromised and will evently lead to premature clear failure.



The UV inhibitors are only in the upper 0.2mls of the clear, which on an OEM finish is probably 0.6-0.8 at best.



Be happy that you didn't burn through the paint initially!



Paco
 
Note: The clear addition depends on the type of paint that was used for the touch-up.



Lacquer pens don't need clear for color matching.

If you used a urethane based touch-up. Then you need to add clear.



Paco
 
what the heck are they doing putting 600 in a kit let alone a piece of 250!!!!!!! 1000 i can see. Have any of you guys heard of micro mesh. Back in my model building days, I used their sand papers to flatten model car paint finishes. They have papers that go all the way up to 20,000 grit. Not a typo twenty thousand grit. They are very expensive but worth the price to do paint touch up repairs.
 
Thanks JJ, I stand corrected. The sheets only do go up to 12,000 grit. Its been years since I built models. I am so glad you pointed me to this link. micro mesh papers have so many uses. I have used them to polish out scratches in plastic head lamps, guage faces, and even scratches in cd's. They are expensive but soooo worth it.
 
I think I am going to experiment on a scrap hood with their sanding discs. There are distributers in my area and I am very curious what benifits sanding with a DA all the way up to 12,000 grit can bring. I will try to photograph(try is the key word here. I can take pictures to save my life) each step all the way up to an LSP This stuff Im sure will be great for acid rain damage or even bird bomb damage. Time will tell
 
sorry throttle thumb i didnt mean to correct you. Just was giving the guy a site to get some better paper. I'd also go with Unigrit least I have used on a car is 2000, i feel 1500 is still a little harsh.
 
No problem JJ. I wasnt being sarcastic. I thank you for that link. I would love to get more of this stuff. Its one of those have to use it to appreciate it products. Their website offers samples if you register so I asked for a sample of each of thier discs to use with my hutchins DA so I can go through all of their steps. I remember polishing out model bodies and spending ungodly hours perfecting the finish for contests as a kid. 20 hours of polishing a 1/25 scale model wasnt out of the question.
 
no more sanding for me! lol!!!



i am gonna borrow my friend's Langka bottle to smooth out the basecoat, then apply my Clearcoat and use rubbing compound to smooth and polish that.



my WRX is a daily driver, so I'm not allll that disappointed. but i learned a valuable lesson! thanks all.
 
I'd just like to give you a pat on the back for a try. touch up work is definitely risky business and there are many that wouldn't even be willing to try it. Your post is knowledge added to this community and knowledge that will come in handy for others. Thanks.
 
Unigrit is cost effective from Meguiars and more then enough for automotive use. The micromesh and similar products are very expensive. Good stuff. I had a 4000 sheet and it's made very well but personally, I don't think for Automotive use, it's worth the extra expense.



If I was really worried about it, I'd probably spend the money and get one of those Norton Spot Detailing kits or the 3M Trizac ssystem and offer up the service on the side to friends, neighbours etc. to make up for the cost of purchasing the kits (~$200 - $400) + plus an air setup.



Paco
 
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