Use a DA polisher after wet sanding?

[MJT]

Hi there. A friend has asked me if I would detail/take out some deep scratches on his car (having scraped it in a parking lot). I am wondering can I wet sand these individual scratches and then use my DA polisher with m105? I don't own a rotary.

And how coarse of a sand paper should I use?? Am I right in thinking a DA polisher is limited to how coarse the sand paper used is?

Thanks!

[jamesboyy]

if the scratches catches your finger nail or if you can feel them in any way then you have to use touch up.paint but if it dont catch fingernail try 2500 or 3000 grit sandpaper then polish it out

[Mike Phillips]

Not sure what you're up against, maybe you can post a picture?

Before you dive into wetsanding a factory thin clearcoat, maybe give this thread a read through and educate your buddy that sometimes it's safer to improve scratches than try to remove scratches...


Here's the thread...


New to scratch removal w/ questions. (http://www.autogeekonline.net/forum/auto-detailing-101/65856-new-scratch-removal-w-questions.html)

Before

http://i.imgur.com/cxKGmMZ.jpg


After Compounding Only
Forum member used Ultimate Compound with a DA Polisher.

http://i.imgur.com/VBCzq2x.jpg


The entire thread is a great read and I highly recommend it. The dramatic before and after pictures start on page 4 of the thread.

There's so many great threads like this one on this forum that half the work is just remembering where there at to share them when similar situations pop up.


:)

[Mike Phillips]

If you do decide to wetsand, try to finish out using at a minium #3000 grit by hand or machine. Machine sanding marks are a lot easier to remove than hand sanding marks.

#5000 grit sanding marks are even easier to remove.

Check out these two threads... in the first one, if I can remove sanding marks by hand, you can certianly do it by machine. Get a good compound and one or two of the new THIN Purple Foamed Wool Pads AG carries.


How to remove wetsanding scratches by hand - FG 400 (http://www.autogeekonline.net/forum/ask-expert-featuring-mike-phillips/58151-how-remove-wetsanding-scratches-hand-fg-400-a.html)

http://www.autogeekonline.net/gallery/data/787/Remove_Sanding_Marks_by_hand_009.jpg




:)

[Mike Phillips]

Here's a little article I did and you can see the difference in "Sheen Level" from 4 different levels of sanding discs.


Video: Wow! 3M #5000 Grit Polishing I mean Sanding Discs! (http://www.autogeekonline.net/forum/wet-sanding-cutting-buffing/50222-video-wow-3m-5000-grit-polishing-i-mean-sanding-discs.html)
From left to right...


#1500 Grit Sanding Disc, #1500 Foam Backed Finishing Disc, #3000 Foam Backed Finishing Disc and #5000 Foam Backed Finishing Disc

http://www.autogeekonline.net/gallery/data/834/50003M000.jpg



Good luck and be careful...


:)

[MJT]

Wow thanks Mike! If I can get a photo I will post it to this thread and would appreciate your gut reaction! I am interested in just seeing what the m105 can do alone followed by polishing.

Also I didn't realise there are stages of sanding with different grit papers. Why is that done instead of just using one grade of paper? Is it to smooth out the sanding marks in prep for the compound?

Mark

[Mike Phillips]

Wow thanks Mike! If I can get a photo I will post it to this thread and would appreciate your gut reaction! I am interested in just seeing what the m105 can do alone followed by polishing.



There's so many great threads on this forum documenting before and after that half my forum time is just "remembering" where all this stuff is and the sharing it so,

A: People can learn from those that have been there and already done that.

B: There's no need to re-type or re-invent the wheel when this type of information is already on our forum. (Just needs to be located and shared)







Also I didn't realize there are stages of sanding with different grit papers.

Why is that done instead of just using one grade of paper?

Is it to smooth out the sanding marks in prep for the compound?

Mark


Normally you use a more aggressive paper to cut down orange peel or remove other defects for the SPEED FACTOR.

Then you refine your sanding marks to a higher grit level to,

A: Make the buff out easier and faster.

B: Keep surface temperatures lower as clear coats don't like heat.

C: Make the rotary buffer work easier on you.

D: If you're really good at this you do it in a way that leaves the MOST paint on the car. That is one of the major goals. Make the paint look good while leaving as much of the costly and precious paint actually ON THE CAR.


Too many Cavemen out there that use too aggressive of papers and compounds and not only do they remove too much paint they leave the paint looking hacked-up.


Good luck and please post a follow-up to this thread with some pictures.


:dblthumb2:

[erichaley]

Here's a little article I did and you can see the difference in "Sheen Level" from 4 different levels of sanding discs.


Video: Wow! 3M #5000 Grit Polishing I mean Sanding Discs! (http://www.autogeekonline.net/forum/wet-sanding-cutting-buffing/50222-video-wow-3m-5000-grit-polishing-i-mean-sanding-discs.html)
From left to right...


#1500 Grit Sanding Disc, #1500 Foam Backed Finishing Disc, #3000 Foam Backed Finishing Disc and #5000 Foam Backed Finishing Disc

http://www.autogeekonline.net/gallery/data/834/50003M000.jpg



Good luck and be careful...


:)

Question on these Mike... Do you go from 1500 Sanding to 3000 Finishing and then 5000 Trizact, or do you add in the 1500 Finishing after 1500 Sanding? I ask because there is no 3" 1500 Finishing, only 1000 Finishing... though I have made some out of the 6" ones.

Also, I have both the 3" 1500 Trizact and 3" 1500 Sanding, and I noticed that, other than color, they are identical! Not surprising given that Meguiar's is owned by 3M, but interesting nonetheless.

[MJT]

Thanks Mike! I may end up for safety sake try compounding the scuffs etc with m105 and see what that does! I am not experienced in wet sanding so may be wise to hold off on that. I will try and put a few before and after pics when I end up doing the job.

[Mike Phillips]

Thanks Mike! I may end up for safety sake try compounding the scuffs etc with m105 and see what that does!




This will be a good first approach, you can always try something else later...



:dblthumb2:

[MJT]

Hi Mike & co. below are some before and after photos in response to my recent posts on this thread and your suggestion I post some photos. I decided I would just compound the car with m105 (plus polish etc afterwards) and see how much I could improve the bumper scuffs and scratches. I was pretty pleased. Would love your comments and any advice to improving the correction of deep bumper scuffs etc.

http://www.autogeekonline.net/gallery/data/500/medium/2_before_FR_bumper_scuff_.jpg
http://www.autogeekonline.net/gallery/data/500/medium/2b_before_FR_bumper_scuff_.jpg
http://www.autogeekonline.net/gallery/data/500/medium/2_after_FR_bumper_correction_.jpg

http://www.autogeekonline.net/gallery/data/500/medium/5_before_LR_bumper_scratches_.jpg
http://www.autogeekonline.net/gallery/data/500/medium/5_after_LR_bumper_correction_.jpg

http://www.autogeekonline.net/gallery/data/500/medium/3_before_FL_bumper_scuff_.jpg
http://www.autogeekonline.net/gallery/data/500/medium/3_after_FL_bumper_correction_.jpg

http://www.autogeekonline.net/gallery/data/500/medium/4_before1.jpg
http://www.autogeekonline.net/gallery/data/500/medium/4_after1.jpg

http://www.autogeekonline.net/gallery/data/500/medium/1_after1.jpg

[HateSwirls]

It's possible to remove sanding marks with a DA after sanding but I always make a point to use 3M 3000 un-grit after using 2000-2500, makes it much easier , I have a rotary but prefer taking my time using my DA
Others gave you some sound advice here, read up on wet sanding.

[Mike Phillips]

Just to keep things in context... here's the original post...




Hi there. A friend has asked me if I would detail/take out some deep scratches on his car (having scraped it in a parking lot).




There were questions about wetsanding the paint and the recommendation was to skip wetsanding at least at first and see what could be done just by compounding...





Hi Mike & co. below are some before and after photos in response to my recent posts on this thread and your suggestion I post some photos.

I decided I would just compound the car with m105 (plus polish etc afterwards) and see how much I could improve the bumper scuffs and scratches.

I was pretty pleased.




And you should be pleased. The results while not perfect are dramatic and the car looks SO MUCH BETTER since you compounded and polished it.






Would love your comments and any advice to improving the correction of deep bumper scuffs etc.




I'd stop there. If you want to do more, the compound the worst areas as second time and then polish and wax and call it good.

The reason why is because this is your buddy's car and the question is...


How did it get so bad in the first place and what's changed in the owner and the environment the car is used in that means it isn't going to revert back to how it was before you worked on it?


This is the question I ask all the time and in fact I'm going to write an article on this topic. When dealing with cars like this, I always ask myself or the person doing the work...

What's changed?

And by this I mean, when a car is trashed and now the topic of buffing it out comes up, it's almost always "someone" else than the owner that's doing the buffing. For all kinds of GREAT reasons.

But when it comes to these types of projects... what's changed that after the buffing and waxing the car won't simply be treated the same way it was before the buffing and then simply return to the condition it was in before the buffing.

If the answer to the question, what's changed? is nothing, that is the car owner has not become an on fire detailing enthusiast themselves, then stop doing more work and move on...


If the owner has become an on fire detailing enthusiast, then make them help you do the work not only s they can appreciate what it takes to undo years of neglect and damage but so they know how to do it themselves.

All too often the after a project like this the owner will just go back to the same routine that resulted in the condition you found the car. So why kill yourself over a daily driver?

But yeah... if you want to take the great results you already created to a higher level then compound again... compounding removes paint and levels the surface so that will help but I wouldn't wetsand. Factory paint is already thin to start with, sanding will just make it thinner and it's just a daily driver with a past that shows it's not really a good candidate for more and more work.


I do thank you for the follow-up posts and the pictures.

I really appreciate you uploaded them to our forum gallery so now they will endure over time instead of the lame Photobucket route where down the road the simply disappear and make the thread useless. Wish more people would figure out how to use the forum gallery. It's not that hard, heck I probably load 100 to 300 pictures a week...easy... If I can do it anyone can do if they can simply read.



:dblthumb2: