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SRHTX
02-01-2010, 10:28 PM
Okay. I'm doing this so I will know where I have posted this question. Some people, down here, have come up to me and asked what I could do to solve the wet-sanding problems that other people/companies have done to thier vehicle.

What would "YOU DO" to correct the paint to dispose of the wet-sanding marks. You can see any wet-sand mark at night time when lights are hitting the paint. Feed back please

For example, what would you do to a vehicle that has black paint where you can see EVERYTHING.

No. I have not messed up a vehicle with wet-sanding it, thank you. lol

zinc02gt
02-01-2010, 10:57 PM
Rotary, wool pad, and a steady pair of hands.


I've been working on wetsanding alot recently actually. I have a 2004 black Mustang hood that I've been working on. Asphalt Rocket has been helping me through it with little details and everything.

Patience is key part. Just hope that the folks didn't sand to deep.

LincolnZephyr2006
02-01-2010, 10:59 PM
Well... to stay safe as possible your going to need a paint meter. Many poor body shops or detail shops may have sanded with a lower grit and not proceed to a higher grit and instead, buffing from there. That is when you will have to use your best judgement and grab some 2000-3000 grits to finish to fully correct the clearcoat... and then buffing. But, like I said.... you should use the paint meter to know how much microns you are working with first...

LincolnZephyr2006
02-01-2010, 11:01 PM
Rotary, wool pad, and a steady pair of hands.


I've been working on wetsanding alot recently actually. I have a 2004 black Mustang hood that I've been working on. Asphalt Rocket has been helping me through it with little details and everything.

Patience is key part. Just hope that the folks didn't sand to deep.


ORR if the sanding marks look like they CAN be buffed with a rotary/wool, then you should try this approach first. Always least agressive first... but I am sure you know that...

jlb85
02-01-2010, 11:07 PM
Well, to wet get rid of the marks (assuming they are from a previous attempt at wetsanding long after the body shop) you will have to polish them, assuming you have enough clear left. What are your readings? To polish them, you may need to wet sand with a finer grit, then compound.


However, two things I would look at first:

1) are the sanding marks truly wet sanding marks? Could they be sanding marks from the paint job, and be under the clear? If they are noticeable, they could be either file marks from sanding down filler before paint (that shrinks after some time, worse on the cheaper fillers), or sanding marks during color sanding, or a combination of both.

2) I would get signed waiver for any damage incurred when you fix the work that someone else messed up. Also make sure you have a PTG. Now, if the car has been to the body shop before, a normal PTG might not give you enough info. To really know where the color ends and where the clear begins you will need the expensive PTG.

sullysdetailing
02-01-2010, 11:18 PM
Well... to stay safe as possible your going to need a paint meter. Many poor body shops or detail shops may have sanded with a lower grit and not proceed to a higher grit and instead, buffing from there. That is when you will have to use your best judgement and grab some 2000-3000 grits to finish to fully correct the clearcoat... and then buffing. But, like I said.... you should use the paint meter to know how much microns you are working with first...

This is great advise. After that Rotary Wool Pad, then fallow it up with your foam pads. Make sure not to get to close to the edges.

SRHTX
02-02-2010, 07:05 AM
1) are the sanding marks truly wet sanding marks? Could they be sanding marks from the paint job, and be under the clear? If they are noticeable, they could be either file marks from sanding down filler before paint (that shrinks after some time, worse on the cheaper fillers), or sanding marks during color sanding, or a combination of both.

Well, it's not my friends body shop that did this. One vehicle was an '03 Yellow Cobra that a body shop did a 100% repaint on. Marks were everywhere on the Cobra. Same thing on a black vehicle.

I now have my Flex working once again. I had AG send me TWO BACKING PLATES for my Flex. If one messes up, I will have a back-up unlike the 1st time detailing a persons vehicle having to switch to the PC. Anyways.....

With the Flex, I will have to start with an orange or yellow pad. Should I use Megs 105 for a compounding? After that, I could use Megs 205 with a purple wool pad and so on.

Mike Phillips
02-02-2010, 08:57 AM
I'm going to reverse the order in which jlb85 posted the below,





2) I would get signed waiver for any damage incurred when you fix the work that someone else messed up.


Very important. Before working on the car EDUCATE your customer on reality. Reality is paint is thin and because it's thin doing any kind of repair work for someone else's mistake is risky. Let them know you're game for trying but if a 'mistake' happens, it would have happened to anyone trying to fix the problem due to the paint thinness factor and you want a waiver or exemption for liability or they'll need to find someone else to do the job.


Does anyone have a template for a generic waiver they can share with our forum members? Or can one of our talented forum members with a little knowledge of the law create one?




To polish them, you may need to wet sand with a finer grit, then compound.


One of the things I demonstrated at the 2010 Mobil Tech Expo was how to remove defects by sanding and then compounding out your sanding marks. The benefits were,


Damp-Sanding is cooler than compounding with a rotary buffer and a wool pad.
You regain control over the depth of the defects you're trying to remove.
Because you now control the depth of the defects you have control over how aggressive you need to get with your compound and pad choice.
Pictures from Mobile Tech Expo 2010 (http://www.autogeekonline.net/forum/company-forum-news-headlines/22824-mobile-tech-expo-2010-a.html)






I now have my Flex working once again.


Sanding marks are removed best using a rotary buffer. A rotary buffer is the best tool for the job. Other tools can be used, but nothing will be more effective and time-efficient as a rotary buffer.




With the Flex, I will have to start with an orange or yellow pad. Should I use Megs 105 for a compounding? After that, I could use Megs 205 with a purple wool pad and so on.

With the Flex, might as well go with the yellow cutting pad with M105 since you can stop at any point in the process.

I'll do some sanding and buffing with the Flex today and see if I can come up with a pad combination that works really well for removing sanding marks. Maybe the Purple Kompressor.


:)

sullysdetailing
02-02-2010, 09:31 AM
Mike if you remember back when you had the 102 class on wet sanding I tried getting sanding marks out with the flex da and orange pad. It worked but took 2-3 times longer then the rotary

Mike Phillips
02-02-2010, 12:16 PM
Mike if you remember back when you had the 102 class on wet sanding I tried getting sanding marks out with the flex da and orange pad. It worked but took 2-3 times longer then the rotary

That's why if you re-read what I wrote I said,



Sanding marks are removed best using a rotary buffer. A rotary buffer is the best tool for the job. Other tools can be used, but nothing will be more effective and time-efficient as a rotary buffer.


I never said it couldn't be done it will just take longer.

:)

SRHTX
02-02-2010, 03:03 PM
With the Flex, might as well go with the yellow cutting pad with M105 since you can stop at any point in the process.

I'll do some sanding and buffing with the Flex today and see if I can come up with a pad combination that works really well for removing sanding marks. Maybe the Purple Kompressor.


:)

Mike, please keep me posted about this. I have a Purple Kompressor pad, all of the Kompressor pads, that I have not even used. I really wish to see how you do your correction job. :props:

SRHTX
02-02-2010, 03:31 PM
The Kompressor pads I have are:

Black - 44-7650KR
Orange - 44-2650KR
Yellow - 44-4650KR
White - 44-6650KR
Red - 44-1650KR

Now, here is a green pad that I have. It's the LC # 78-34650DA CCS SOFT

The only purple pad I have is the Wool 7-1/2" x 1" Purple Foamed Wool - #58-4275. That is one of my most favorite pads that I use.

Feed back please

zinc02gt
02-02-2010, 03:36 PM
I would use the PFW. I have a 4" PFW pad that I use to get close to edges, but I always come back on them with the 3M pad. To me, the PFW lets me be a bit more precise but the 3M finishes A LOT better and that's why sometimes I'll use the the PFW then 3M combo. With more practice, I'm sure that i could get the hang of using a 9" wool pad though and get it right on the edges without doing damage. Just gotta be patient.

My guess would be that you need to ether follow the PFW pad with M105 on a white kompressor or M105 on an orange pad. You could try following it up with M205 on a white pad, but from my experiences with the PFW pads it left ALOT of swirls and hazing, MUCH MUCH more than the 3M Superbuff and I follow the superbuff up with a white pad with M205.

SRHTX
02-02-2010, 03:42 PM
Well, I do have a 4" Purple Foamed Wool pad. I can use that lil one if needed.

zinc02gt
02-02-2010, 04:25 PM
I would. I like it, don't get me wrong, it's just that the 3M Superbuff finshes like an orange pad, but has the cut of wool. The PFW also seems to get caked up REAL easily with M105.