How many wet sands to reach the paint?

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dmk112

New member
Can someone tell me how many times would you recommend wet sanding a spot before being in trouble w/ the clear coat?



I have a chip that didn't work out with the touch up paint too well the 1st time (I have white specs in the touch up spot ). So I need to re-touch-up and re-sand and then re-compound and re-polish. Did i use "re" enough? :bat



I'm just afraid of hitting the paint and doing more damage than I started with.
 
dmk112- Welcome to Autopia!



When wetsanding touchups, I'd try to limit the wetsanding to the touchup paint and not hit the factory paint if you can help it (you will hit it some). I'd consider cleaning the first-attempt touchup off with Langka or even lacquer thinner and then starting over.



And remember that it's not just a matter of cutting through the clear- if you remove more than 1/3 to 1/5 of a mil (that's .0003"-.0005" which sure isn't much!) you'll precipitate early clearcoat failure. I sometimes just leave the touchup paint in a "blob", figuring it might not look all that great, but it's not gonna be a *functional* problem.
 
While I make *no* guarantees on this, here's something that I've done before:



Tape off OEM paint, leaving blob above paint



Knock down blob with 1500 (you could probably go as low as 1000 if you really wanted to) grit until it is at level of tape



Remove tape



Take the eraser side of a pencil, pen cap, etc and wrap some 2500-3000 grit around it



Carefully use improvised sanding "pen" on blob only to knock it down to level of factory paint. It is critical to be patient and exacting on this step - good lighting, steady hands are a must.



Make sure to remove all 1500 grit marks from the blob using the pen



Optional : feather sand *very* lightly with 3000 around the blob. I would not recommend it in your case, given that you've sanded before. However, for a first time chip, this helps blend it in.



Polish out (if you use 3000 grit Megs Unigrit papers, you can avoid the need for a heavy compound and knock the marring out with P0106FF or equivalent, saving a little more clear).







This technique works great on superglue, etc too.
 
Thanks guys I'll give that a try. I heard that if you try to sand down just the touch-up then you will get an indentation around it and making it look like a dent?



Also, with the clear coat failure, what exactly happens?
 
themightytimmah said:
Take the eraser side of a pencil, pen cap, etc and wrap some 2500-3000 grit around it
Click to expand...





or take a hole punch and punch out some different grit circles

and use rubber cement to make several "sanding sticks"

out of the eraser side of a pencil
 
BigJimZ28 said:
or take a hole punch and punch out some different grit circles

and use rubber cement to make several "sanding sticks"

out of the eraser side of a pencil
Click to expand...



Is this how you guys do the wet sanding usually or is it because I already wet sanded that area? In David's guide he sands the entire area and so do many other people that have posted on the board.
 
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