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View Full Version : Please advise if my 'wetsanding' technique is correct?(with pictures)


fishbonezken
Nov 17th, 2006, 05:36 AM
Hi all,
I recently worked on an older model Honda Civic, and there was this scuff mark on the door, which I tried to remove with ColorX. It removed only very little and it took too much elbow grease.

So I tried using M80 by hand, removed faster, but the scuff mark was too thick. It would take too long.

Then I decided to try 'wetsanding'. I have no experience what so ever, and I didn't know that I was suppose to soak the sandpaper in water prior to use.

I took a generic 1500 grit sand paper, cut it into a small rectangle and sprayed on soapy water onto the scuff mark and onto the paper.

Then I sanded carefully and [/B]lightly. To my horror, I saw sanding marks, the paint appearred to be chalky, I was terrified. OMG I spoiled the paint, and it is not my car!

I tried to remove with colorX by hand, it faded just a little, and then i tried M80 by hand with a terry towel, the sanding mark dissappeared! So I got confident and tackled other spots like this one.

[B]Before
http://archive.meguiarsonline.com/forums/photopost/data/500/scuff1.jpg

During
http://archive.meguiarsonline.com/forums/photopost/data/500/scuff2.jpg

After
http://archive.meguiarsonline.com/forums/photopost/data/500/scuff3.jpg

I sanded like this, should I use a sanding block? The scuff mark was very thin, so I tried to sand the area itself and not too much paint around it.

http://archive.meguiarsonline.com/forums/photopost/data/500/wetsand_1.jpg
http://archive.meguiarsonline.com/forums/photopost/data/500/wetsand_2.jpg

And this is the result after :

a generic 1500 grit sandpaper
M80
terry towel
Soapy water
lots of elbow grease

http://archive.meguiarsonline.com/forums/photopost/data/500/medium/wetshine_2.jpg

Am I doing anything wrong?
All comments/critiques/advice would be greatly appreciated. Thank You!

Mike Phillips
Nov 17th, 2006, 08:37 AM
Actually, it looks like you're process is working. Here's one thing you might want to do and that's inspect your results in different lighting conditions because sometimes it can be hard to see surface imperfections, (like leftover sanding marks), unless you're in the right light.

Removing sanding marks by hand must be very challenging, of course this depends upon how hard or soft the paint is; usually people use a rotary buffer and a compound to remove sanding marks and typically M80 Speed Glaze by hand will not be effective enough to count on as a sure-fire process.

BlueZero
Nov 17th, 2006, 08:44 AM
The before and after shots look great. I'd say you did something right. :xyxthumbs

I'm not a wet-sanding pro. I've only done it twice. But one thing I learned is if your going to use 1500 grit, follow up with 2500 grit. It's allot easier to get out the sanding marks.

This was my first try...
http://meguiarsonline.com/forums/showthread.php?t=16536

fishbonezken
Nov 17th, 2006, 12:23 PM
Actually, it looks like you're process is working. Here's one thing you might want to do and that's inspect your results in different lighting conditions because sometimes it can be hard to see surface imperfections, (like leftover sanding marks), unless you're in the right light.

Removing sanding marks by hand must be very challenging, of course this depends upon how hard or soft the paint is; usually people use a rotary buffer and a compound to remove sanding marks and typically M80 Speed Glaze by hand will not be effective enough to count on as a sure-fire process.

Thanks Mike!
I'll try to look at it with different lighting conditions. The pictures only okay under normal light. Maybe there were more marks left if it is looked under a 500w halogen lamp? thanks for the tip.

fishbonezken
Nov 17th, 2006, 12:27 PM
The before and after shots look great. I'd say you did something right. :xyxthumbs

I'm not a wet-sanding pro. I've only done it twice. But one thing I learned is if your going to use 1500 grit, follow up with 2500 grit. It's allot easier to get out the sanding marks.

This was my first try...
http://meguiarsonline.com/forums/showthread.php?t=16536

oh yes, I'll have to get me a sheet of 2500 grit sandpaper. Your first try was quite successful too.
Btw, did you notice that the water around the sanded area becomes a little bit whitish?
I've read that this is the clearcoat being washed away.
would you happen to know that if this is normal?

BlueZero
Nov 17th, 2006, 12:44 PM
Btw, did you notice that the water around the sanded area becomes a little bit whitish?
I've read that this is the clearcoat being washed away.
would you happen to know that if this is normal?

Mine did the same thing. Left a spot on the nice new garage floor too. I would think it's normal because that's what you want to do is remove some of the clear coat. I get a sick feeling while I'm doing it, worrying about taking off all the clear. :eek: I don't think I'll do anymore wet-sanding until I get a junk body panel to practice on.

Superior Shine
Nov 17th, 2006, 01:28 PM
You can't argue with good results but I see a few things I would do different.

First, the paint transfer could have been removed with mineral spirits or simiular solvent.

Keep some abrasive cleaners on hand (#85) for just that type of thing that solvent is too much over kill for.

Also, sanding like that will get you in trouble one day. Use a block when possible.

Again nice work.

sneek
Nov 17th, 2006, 02:21 PM
Couldn't you remove that paint transfer by using clay followed by DC1?

fishbonezken
Nov 17th, 2006, 07:56 PM
Mine did the same thing. Left a spot on the nice new garage floor too. I would think it's normal because that's what you want to do is remove some of the clear coat. I get a sick feeling while I'm doing it, worrying about taking off all the clear. :eek: I don't think I'll do anymore wet-sanding until I get a junk body panel to practice on.

I feel the same too. yes a junk body panel is good for practise.
Then we can see how easily we can sand through the clear.
:eek: :D

fishbonezken
Nov 17th, 2006, 07:58 PM
You can't argue with good results but I see a few things I would do different.

First, the paint transfer could have been removed with mineral spirits or simiular solvent.

Keep some abrasive cleaners on hand (#85) for just that type of thing that solvent is too much over kill for.

Also, sanding like that will get you in trouble one day. Use a block when possible.

Again nice work.

Thank You Joe !

I did not know that mineral spirits could remove the paint transfer, will it be harmful to the car's paint that it's being worked on?
Yes, I'll use a block next time.

Thanks again. :)

fishbonezken
Nov 17th, 2006, 08:01 PM
Couldn't you remove that paint transfer by using clay followed by DC1?

Hi sneek,
I tried claying, it did not remove much, maybe because the clay I was using was a mild one.
I did not try DC1, but went ahead with ColorX by hand, it removed very little of the paint transfer. So I went ahed with 'wetsanding'.
Should've tried mineral spirits first, as mentioned by Joe of Superior Shine above.

Thanks though!

noswirler
Nov 17th, 2006, 08:14 PM
take it out and give it a normal wash and dry and look at it in the sun it will definitely show any left over sanding marks. just curious why would you start so harsh (1500) , you know the whole least abrsive product thing.