Scratch repair - wet sand, compound, polish tips

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Howdy folks. Background - last winter, an inlaw who'll remain nameless decided to "help" us during a snowstorm by clearing the snow off our silver 2006 Honda Accord - with a snow shovel. Needless to say it has a copious amount of scratches ranging from the fine type that don't or just barely catch a finger nail up to nasty wide scrapes down to the primer. Every panel has some of them. In addition to that, the bumpers have scrapes down to the plastic from my wife's parking lot misadventures.

So I'm using this mess as an opportunity to learn about paint repair, starting with scratch "removal". Phase 2 will be scratch repair with touch up paints, and phase 3 will be major repairs with spray on paints.

I am starting with the trunk, as it has a number of scratches of all kinds, and I figure the worst thing that can happen is I completely screw it up and have to pay to have it repainted.

Did some googling and youtubing and settled on this approach for the first set of scratches, those that don't or just barely catch a fingernail:
- wet sand with 1500, 2000, 2500, and finally 3000 grit 3M papers. Mixed up some soapy water in a spray bottle and used a 3M foam pad to do the sanding.
- hand apply rubbing compound with a Meguiar's foam pad (Turtle Wax "premium" in the bottle)
- hand apply polish with another Meguiar's foam pad (Meguiar's Ultimate Polish)

The first set of 3 scratches were removed by the 1500 and 2000 papers, the 2500 and 3000 reduced the haziness. The compound reduced it further and the polish reduced it almost altogether. The result looks OK from some angles, but in reflected light there's a pretty clear difference in the sheen for lack of a better word. Unfortunately in my haste I didn't take any good pictures.

Thoughts on how to get the end result to match the unblemished paint? I do not have a great sense as to how much pressure or for how long to sand during each step. I used what I'd call a moderate amount of pressure, not pressing very hard but certainly more than just sorta gliding the paper across the surface. Likewise I used a fair amount of pressure for the compound and polish, wiping both clean immediately after each application.

I do not have a DA polisher but am not opposed to getting one at some point if it would be a better tool for the job.

Any advice you guys have would be greatly appreciated. Thanks,

jeff
 
Id say get a HF DA. When on sale they are 58-60$ and work quite well. Try and practice on someones beater or start out slow.
 
Last edited:
Originally Posted By: greenjp
Howdy folks. Background - last winter, an inlaw who'll remain nameless decided to "help" us during a snowstorm by clearing the snow off our silver 2006 Honda Accord - with a snow shovel. Needless to say it has a copious amount of scratches ranging from the fine type that don't or just barely catch a finger nail up to nasty wide scrapes down to the primer. Every panel has some of them. In addition to that, the bumpers have scrapes down to the plastic from my wife's parking lot misadventures.

So I'm using this mess as an opportunity to learn about paint repair, starting with scratch "removal". Phase 2 will be scratch repair with touch up paints, and phase 3 will be major repairs with spray on paints.

I am starting with the trunk, as it has a number of scratches of all kinds, and I figure the worst thing that can happen is I completely screw it up and have to pay to have it repainted.

Did some googling and youtubing and settled on this approach for the first set of scratches, those that don't or just barely catch a fingernail:
- wet sand with 1500, 2000, 2500, and finally 3000 grit 3M papers. Mixed up some soapy water in a spray bottle and used a 3M foam pad to do the sanding.
- hand apply rubbing compound with a Meguiar's foam pad (Turtle Wax "premium" in the bottle)
- hand apply polish with another Meguiar's foam pad (Meguiar's Ultimate Polish)

The first set of 3 scratches were removed by the 1500 and 2000 papers, the 2500 and 3000 reduced the haziness. The compound reduced it further and the polish reduced it almost altogether. The result looks OK from some angles, but in reflected light there's a pretty clear difference in the sheen for lack of a better word. Unfortunately in my haste I didn't take any good pictures.

Thoughts on how to get the end result to match the unblemished paint? I do not have a great sense as to how much pressure or for how long to sand during each step. I used what I'd call a moderate amount of pressure, not pressing very hard but certainly more than just sorta gliding the paper across the surface. Likewise I used a fair amount of pressure for the compound and polish, wiping both clean immediately after each application.

I do not have a DA polisher but am not opposed to getting one at some point if it would be a better tool for the job.

Any advice you guys have would be greatly appreciated. Thanks,

jeff


I would have come unglued!!! I am subscribed so feel free to post pics and keep us updated, sorry for your misfortune.
 
My teenage niece did that to my brother's Sonata. Luckily damage was limited to the trunk before he stopped her. I would have lost my mind, he was much more composed than I!
 
The issue you're having is that the sanded areas have less texture than the originally painted areas. There are sandpapers available, such as Meguiars' unigrit finishing discs, that will preserve the paint's texture while removing defects.

Secondly, be advised that factory paint is thin. Really thin. I would not sand with 1500...2000 at most. Most compounds should be able to remove 2500 to 3000 grit so I definitely would not do more than one follow-up sanding step in order to minimize the amount of material removed. If you do not have a paint thickness gauge, I would consider getting one to get a ballpark idea of the total film thickness that you may be working with.

I'm not sure what your risk tolerance level is, but I would probably leave this job to someone who has done this before.
 
Great stuff guys, thanks. Keep it coming
11.gif


I was very displeased when I saw what happened to the car, but at the same time I'm at a point in my life where being angry about this sort of stuff doesn't get me anywhere. So as I said I'm using this as a learning opportunity - as much so I am better prepared in the future to address scratches as they appear on our newer car (2015 Odyssey) as getting this car looking better. I am pretty handy and good at learning things so this sort of project is right up my alley.

As for risk tolerance, I figure by focusing on this one panel the worst case scenario is I truly screw it up and have to pay a few hundred to have it repainted. So I guess my risk tolerance is pretty high.

All that said it sounds like a two-step sanding routine, perhaps 2000 or 2500 followed by the 3000 would be a safer plan. Follow that up with a DA compound & polish of the entire panel to go for a more uniform finish? I see JHRZ2 has a DA pad thread going now so I'll go peruse that...

jeff
 
Did you inform them of how much damage they did and that they are an idiot? Did they offer to pay for the damage they caused?
 
Now with pictures! Here are some representative shots of the damage. Note, all of these were run through some mild post-processing, adding some contrast to make the scratches more visible.

P1120983_65 by Jeff Green, on Flickr

P1120985_65 by Jeff Green, on Flickr

P1120989_65 by Jeff Green, on Flickr

P1120990_65 by Jeff Green, on Flickr

And the coup de grace...
P1120984_65 by Jeff Green, on Flickr

Also here are the front corners. My wife has some issues estimating where the corners of the car are
21.gif

P1120987_65 by Jeff Green, on Flickr

P1120988_65 by Jeff Green, on Flickr

Now, the good news is the black leather interior of the car is in excellent shape, and the car runs beautifully with 103k miles.

Here are a couple photos of the issue I'm talking about with the sheen being different. First is a spot that was sanded with 1500, 2000, 2500, and 3000, then compounded and polished. The second was only sanded with 2500 and 3000, then compounded and polished. These pictures were taken such that the lighting emphasizes it; from some angles and different lighting conditions you don't see a difference.

P1120981_65 by Jeff Green, on Flickr

P1120982_65 by Jeff Green, on Flickr

So there you go.
 
Yikes!
I am a pro detailer and here is what I see.

For the areas that have a loss of sheen, it looks from my eyes that the clear coat is sanded/polished through, which is very easy to do- especially on a Honda. Imho, Honda has some of the worst paint quality of all of the major manufacturers. If I am correct, then the only way to repair is to respray the panel.

As for the scratches, they can be minimized by polishing. My suggestion (as stated earlier)- pick up a HF DA polisher.
Then jump on Autogeek and order up a couple of 6" polishing pads. One medium cut and another light cut- these will serve you well for 95% of what you will be doing. Also pick up an 8oz bottle of Menzerna FG400 and PF2500.

Use the FG400 first with the medium pad. Gently polish the scratch area until it looks "better" (its a judgement call). Then follow with a light pad and the P2500 and polish until it the area looks good to you. It might be worthwhile to polish the entire car with the 2500 and then wax/ seal with your favorite product.

Fire away with any questions! Good luck and have fun with it!
 
milehigh is correct.

if you need more info or want to buy better supplies or to pick up a DA buffer, create an account at autogeekonline.net and/or autopia.org and ask those guys. plus they are having some sales right now

they are OCD about detailing just like we are OCD about all things oil related
 
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