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jmitch8011
Jul 23rd, 2008, 12:03 PM
I have looked this up and even watched the YouTube video but I'm still not clear on when this should be used. I know on here there was a place where they could not get a machine so they wet sanded but I just wanted to get clarity. I would like to try this but I don't want to jump in and realize I just customized my ride! :chuckle1 Anyway, Fire when ready!:xyxthumbs

PorscheGuy997
Jul 23rd, 2008, 12:39 PM
There are a number of uses for wet sanding. The primary reason is to remove the orange peel and flatten the paint (mirror like reflection).

Wet sanding is also used to correct serious scratches and scrapes.

The process of wet sanding is basically putting fine scratches into the paint. Then, you would compound them out to reveal a perfect finish.


Unless you are sure that the paint is thick enough to sand, I would use it as a last resort if compound and polishing fail to remove the scratch.

Be careful!!! It's very easy to thin out the paint too much. Then, clearcoat failure is possible in the future.

Also, proper lubrication and quality papers are mandatory. Low quality papers will leave tracers and random, deeper scratches because the grit is not even. The Unigrit papers are the best I have ever used, by far.

jmitch8011
Jul 23rd, 2008, 12:55 PM
thanks. I watched the video of them wetsanding and he showed the white liquid was clear coming off the hood. You answer was exactly what I was looking for. Now 1 question. I read where one person used touch up paint to leave with the surface and then wet sanded after allowing to dry for a long time. In t his fashion can the mark be made almost invisible after buffing?

jpitt1987
Jul 23rd, 2008, 01:12 PM
http://meguiarsonline.com/forums/showthread.php?t=25592

They talk about using touch up paint and sanding in this post.

jmitch8011
Jul 23rd, 2008, 01:24 PM
hey thanks jpitt1987

jpitt1987
Jul 23rd, 2008, 08:32 PM
No problem, I'm glad I could help!

Mike Phillips
Jul 28th, 2008, 06:28 AM
The majority of all wet-sanding is done on fresh paint within a few days of being painted at a body shop. If it is known that the paint is going to be sanded then the painter usually sprays extra layers of clear to insure there is plenty of film-build for the guy doing the sanding and buffing so he can safely sand and buff the paint without out the risk or fear of removing too much clear paint and revealing the basecoat underneath.

When the paint is new as in fresh, as in a few days old it is still soft enough to remove your sanding marks out of it using a rotary buffer.

Now follow me on this...

It's easy to sand paint, (whether it's fresh or cured), sanding is putting scratches into the paint. Anyone can do this. The trick is getting them out of the paint, (not everyone can do this). :D

When paint is still fresh it is soft enough to buff the sanding marks out of relatively easy. When paint is cured, or for example if the paint on your car is the factory baked on paint, (It's fully cured and hardened), then removing sanding marks is very difficult and sometimes impossible.

So here's the deal... detailing enthusiasts and car owners surf the different detailing forums and read about wet-sanding and then think that it applies to whatever it is they're working on... they don't understand the part about fresh paint and cured/hardened paint and how this GREATLY affects a person's ability to remove the sanding marks.

Then some forums have people recommending to not only wet-sand factory baked-on paints, they also recommend or suggest (to the person inquiring for help) that they can remove the sanding marks using a DA Polisher, not a rotary buffer.

And while it's true you can remove sanding marks using a DA Polisher it's not EFFECTIVE and it's not QUICK and it's not EASY. Heck it's not quick and easy with a rotary buffer so it's certainly not going to be quick and easy with a tool that has a clutch that stops the pad rotating when you push too hard, hold the pad at an angle or are buffing on any kind of high point.

Nutshell summary...

Wet-sanding is a process used on fresh paint because the paint is still soft enough to remove your sanding marks out of relatively easily.

And in the context of this thread, fresh paint means a few days old, not a few months or a year.

:)

jpitt1987
Jul 28th, 2008, 11:04 AM
Thanks Mike! That really clears up a lot of confusion in my mind regarding fresh vs cured paint wet sanding. Know that I have a pretty firm grasp of it, my next questions is:

Is wetsanding cured paint ever adviseable? What are the potential problems of wetsanding cured paint?

Actually a two part question, haha. Once again thanks for the info.

-jpitt

Mike Phillips
Jul 28th, 2008, 11:22 AM
Is wet-sanding cured paint ever advisable?

What are the potential problems of wet-sanding cured paint?



The problem with wet sanding cured paint is that the harder the paint the more difficult and the l-o-n-g-e-r it will take to buff your sanding marks out.

If you're talking about a factory finish then the problem is not only is the paint hard but it's usually on the thin side, not the thick side, so you have no room for error and even if you're really good at this type of work it's still risky when you start talking about sanding and buffing an ENTIRE car.

A little spot is one thing, the entire car is a whole different issue.

For what it's worth... you couldn't pay me to wet-sand, cut and buff the entire finish on a new car. Not worth the risk if a mistake is made and that means I have to buy the car owner a paint job.

This was my last full wet-sand, cut and buff job and it had plenty of extra clear paint sprayed onto it because the painter knew we were going to sand and buff it out.

http://archive.meguiarsonline.com/forums/photopost/data/648/StangWerksCustomMach1001.jpg



Suppose to do this one next week...

http://archive.meguiarsonline.com/forums/photopost/data/648/showmustang001.jpg



Shop owner knows to tell the painter to spray more clear and show owner knows to charge his customer more money for more for the labor, time and materials as there's no free lunch.


:)

jpitt1987
Jul 28th, 2008, 12:14 PM
I love those cars! Wow!

In the realm of cured paint, it all comes down to how thick the clear is to begin with and how much of an area you are wanting to work. Correct?

Would you say that WS is sort of a last resort in trying to correct paint due to the abrasiveness of the process? That it should only be done when compounding and polishing don't work?

I know that new finishes and orange peel require it, but I am asking in reference to swirl and defect removal.

Thanks again Mike.

Mike Phillips
Jul 28th, 2008, 01:07 PM
I love those cars! Wow!

Would you say that wet sanding is sort of a last resort in trying to correct paint due to the abrasiveness of the process? That it should only be done when compounding and polishing don't work?



Yes.

Meguiar's always teaches people to use the least aggressive product to get the job done.

So usually you would try wet-sanding last. There are times when wet-sanding is safer than compounding but that would be for removing RIDS which stands for Random Isolated Deeper Scratches.

But this is an advanced procedure and involves using a rotary buffer first to remove light scratches which results in the deeper scratches standing out like a sore thumb.

Check out this thread...

Feathersanding (http://meguiarsonline.com/forums/showthread.php?t=3720)


What we've seen in the last few years is in increase in people wanting to wet-sand their car's paint to get it flawless or to remove orange peel and what they don't understand is that most all wet sanding is done on fresh paint at a body shop where a car has been repainted.

Because they read about wet sanding on other forums they don't get this aspect on the topic of wet sanding thus they are confused.

:)

jmitch8011
Jul 28th, 2008, 01:24 PM
Hey Mike! Thank you Thank you Thank you because I was already scared to even try it on my car let along a customer's car but that makes a lot of sense now. I only have about 4 mils on my car but apparently the paint gauge used may not be exact so I'm waiting on my responses to my topic. Anyway, I probably will not try this unless it's a open call and no danger is invovled.

jpitt1987
Jul 28th, 2008, 08:42 PM
Wow, people could really do some serious damage to their paint finishes! Thanks for shedding some light on that. I know I'll be sure to pass the info along to any of my friends who think that wet sanding is child's play.

Thanks!

Oh, I am hoping to move to Pasadena within the next year and hopefully I can make it to one of the classes in Irvine!

jpitt1987
Jul 28th, 2008, 08:50 PM
Oh and by the way that article on feather sanding was quite informative, thank you. I'll have to try practicing that on some spare parts. I am really excited, my Makita 9207 comes in tomorrow!