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jach
10-19-2011, 03:30 PM
I've been trying to figure out how to get rid of scratches after wetsand with 2000 grit wetsanding on fresh clearcoat (about 12 hours after painting) but still can't figure out why there are still scraches after polishing but my part is shinny.
Is 2000 grit still to harsh on the fresh paint? but I read most polishing compound will remove even 1200 grit.

Len
10-19-2011, 04:11 PM
I've been trying to figure out how to get rid of scratches after wetsand with 2000 grit wetsanding on fresh clearcoat (about 12 hours after painting) but still can't figure out why there are still scraches after polishing but my part is shinny.
Is 2000 grit still to harsh on the fresh paint? but I read most polishing compound will remove even 1200 grit.

Are you using a good brand name sandpaper? Some off-brand products will generate an inconsistent scratch that can be difficult to remove. Also, sanding on clear that has not fully hardened can generate deeper scratches that can be difficult to remove after the clear is hard. So after sanding it's best to do the initial polishing immediately then polish again after it fully hardens.

jach
10-19-2011, 07:16 PM
how long is fully cured? I thought it's easier to polish when it is NOT fully cured which I read somehwere from this forum and also what is the last grit I should use when use sure polish?

Dennis N. Schmidt
10-19-2011, 09:52 PM
Most people jump the gun when colorsanding and buffing new clear.

Typically, unless you have baking capability (140F for an hour) which here in Phoenix means leaving the car in the sun for an hour, you need to wait for the clear to shrink and that takes a couple of days.

Here's what I typically do.

The day after (once again I live in the hottest major city in America so that's all I have to wait):

1) Remove most of the orangepeel using whatever grit it takes; on cars with considerable orangepeel that means starting with P800 on a short throw random orbit sander. If the job's pretty smooth start with P1200. This is all done dry. Get down to flat with this initial step. I sand the areas I can't get the sander into using P1500 wet using well soaked paper (at least 1 hour).

2) Come back with P2000 Abralon or SiaAir foam discs, after that P3000 Trizact or P4000 Abralon or SiaAir all this is done using the short throw random orbit sander. All of these products are used moist. (spritz bottle)

3) Buff out first time. This goes much faster if you've done step 2 above. I always start my buffing with a wool pad. Remove everything with the wool pad. If you can see anything other than swirl marks keep buffing with wool until it's gone.

4) Switch to foam (orange, blue or black) and buff using a good polish. I use SureFinish for this step. I also use a dual action machine for this step but a rotary is completely acceptable as well.

5) Wait a week. During this time the paint will shrink to it's final form and you will see everything you missed the first time around. Using a BLACK Stanford EXPO dry erase marker (not the new low odor version but the original dry erase markers that smell bad - available at Staples) circle all of the problem areas so that you can go back and give them attention. I use this particular brand and type of marker because it can be removed with NO RESIDUE OR GHOSTING from a polished surface.

6) Attack problem areas with P2000 wet paper that has soaked at least an hour in water. The three brands I trust are Starcke (Germany), Eagle (Japan) and 3M Imperial (USA - the yellow backed stuff) Indasa (Portugal) makes a very good wet-or-dry paper too but it's made from aluminum oxide rather than silicon carbide and because of this you must use one grade finer paper (in this case P2500) Buff with wool then subsequently buff with foam. You don't remove scratches and problem areas by buffing you do this with sandpaper. Buffing only brings up the shine.

7) Now you're done.

You almost always have to buff twice. No matter how good it looks after the first buffing you will see problems a week later.

jach
10-19-2011, 10:51 PM
you answered a lot of my questions
I think my problem was I did not soak the sand paper before I start sanding on the fresh paint surface and that leaves deep scratches. So I guess wool pad is what really removes all the scraches from the sandpaper?
I am using one of the cheaper clear coat from kustom shop. Is there differences between different clearcoat brands for polishing? (easier or harder to polish)

Len
10-19-2011, 11:19 PM
you answered a lot of my questions
I think my problem was I did not soak the sand paper before I start sanding on the fresh paint surface and that leaves deep scratches. So I guess wool pad is what really removes all the scraches from the sandpaper?
I am using one of the cheaper clear coat from kustom shop. Is there differences between different clearcoat brands for polishing? (easier or harder to polish)

There can be a big difference in brands of clear and you almost always get what you pay for. There can be difference in hardness, UV resistance, compatibility with the base, film build, etc, etc.

Kerry
11-25-2011, 07:09 PM
Most people jump the gun when colorsanding and buffing new clear.

Typically, unless you have baking capability (140F for an hour) which here in Phoenix means leaving the car in the sun for an hour, you need to wait for the clear to shrink and that takes a couple of days.

Here's what I typically do.

The day after (once again I live in the hottest major city in America so that's all I have to wait):

1) Remove most of the orangepeel using whatever grit it takes; on cars with considerable orangepeel that means starting with P800 on a short throw random orbit sander. If the job's pretty smooth start with P1200. This is all done dry. Get down to flat with this initial step. I sand the areas I can't get the sander into using P1500 wet using well soaked paper (at least 1 hour).

2) Come back with P2000 Abralon or SiaAir foam discs, after that P3000 Trizact or P4000 Abralon or SiaAir all this is done using the short throw random orbit sander. All of these products are used moist. (spritz bottle)

3) Buff out first time. This goes much faster if you've done step 2 above. I always start my buffing with a wool pad. Remove everything with the wool pad. If you can see anything other than swirl marks keep buffing with wool until it's gone.

4) Switch to foam (orange, blue or black) and buff using a good polish. I use SureFinish for this step. I also use a dual action machine for this step but a rotary is completely acceptable as well.

5) Wait a week. During this time the paint will shrink to it's final form and you will see everything you missed the first time around. Using a BLACK Stanford EXPO dry erase marker (not the new low odor version but the original dry erase markers that smell bad - available at Staples) circle all of the problem areas so that you can go back and give them attention. I use this particular brand and type of marker because it can be removed with NO RESIDUE OR GHOSTING from a polished surface.

6) Attack problem areas with P2000 wet paper that has soaked at least an hour in water. The three brands I trust are Starcke (Germany), Eagle (Japan) and 3M Imperial (USA - the yellow backed stuff) Indasa (Portugal) makes a very good wet-or-dry paper too but it's made from aluminum oxide rather than silicon carbide and because of this you must use one grade finer paper (in this case P2500) Buff with wool then subsequently buff with foam. You don't remove scratches and problem areas by buffing you do this with sandpaper. Buffing only brings up the shine.

7) Now you're done.

You almost always have to buff twice. No matter how good it looks after the first buffing you will see problems a week later.

Thanks Dennis, nice write up!

Henry
11-26-2011, 10:39 AM
you answered a lot of my questions
I think my problem was I did not soak the sand paper before I start sanding on the fresh paint surface and that leaves deep scratches. So I guess wool pad is what really removes all the scraches from the sandpaper?
I am using one of the cheaper clear coat from kustom shop. Is there differences between different clearcoat brands for polishing? (easier or harder to polish)

Your paper was too dry (being new) and you might think of using a little Dawn for dishes soap as a lubricant in your bucket of water. You can make some real nasty looking scratches from the edges of paper that is new and that's why you gotta let it soak.

Better still, if you don't do it now, then color sanding with the short throw DA and FinishFilm is the way to go. I bought some FinishFilm from Len years ago and it sat for over 6 months before I got the nerve to try it. I just could not believe I could take DA to my fresh paint. All you need is the right DA (short throw) and the right grit paper. Other than small close areas I do it all with the DA. Even at that, for those small hard to get at areas I use the finish film from the DA. Works great.
I do it all dry and can see where I'm at through what I've sand in relation to orange peel as the shiny dots show clearly so I know I need a little more sanding. I only sand with 1200 - 1500 and that works for me followed by SureFinish. I do get some dullness in a couple days and have to buff again. I attribute this to sanding too early and not going the extra mile with finer grits of FinishFilm.

CAUTION: always make certain you have enough clear on the surface the more sanding you do. You always want a good 2 coats of clear LEFT on the FINISHED surface. You get below that an you comprimize the UV protection of the clear. Henry

Robert
12-07-2011, 10:59 AM
"You almost always have to buff twice. No matter how good it looks after the first buffing you will see problems a week later."

Those are words to live by. After all these years, I still go back and check my work a week later and there's always something. I think my eyes check out after a certain amount of time and lighting changes show different problems so, even my trusty headlamps don't catch everything.

Robert

gtome
01-18-2012, 08:01 PM
Damn it! I came on here tonight to look for the videos. I have been painting for 12 years or so, and never felt confident, and to be honest, have hated polishing. It just never goes how I think it should and I think I am working way harder than I need to. But I always clear, then wait 3 days, then wetsand and polish. Although that does usually take me a couple days to do. Anyway.....Friday I painted and cleared, then monday/tuesday wetsanded, and today did my 3 step polish. It sucked and was a mofo, but it looks pretty good. I did find a couple scratches I missed. Not real bright where I polish (and paint for that matter). i will not be happy if I have to go at it all over again next week!

I always found it odd that I saw here somewhere that the average was 10 hours to wetsand and polish. Takes me 2 to 3 times that to do it!! I also wetsand by hand. Seems everytime I try to use the DA I get pigtails. But I have the short throw DA, interface, and paper. This last job was a big red 66 Impala by the way. I dont have a ton of orange peel either, but I only paint a few a year at best.

Len
01-18-2012, 10:54 PM
Damn it! I came on here tonight to look for the videos. I have been painting for 12 years or so, and never felt confident, and to be honest, have hated polishing. It just never goes how I think it should and I think I am working way harder than I need to. But I always clear, then wait 3 days, then wetsand and polish. Although that does usually take me a couple days to do. Anyway.....Friday I painted and cleared, then monday/tuesday wetsanded, and today did my 3 step polish. It sucked and was a mofo, but it looks pretty good. I did find a couple scratches I missed. Not real bright where I polish (and paint for that matter). i will not be happy if I have to go at it all over again next week!

I always found it odd that I saw here somewhere that the average was 10 hours to wetsand and polish. Takes me 2 to 3 times that to do it!! I also wetsand by hand. Seems everytime I try to use the DA I get pigtails. But I have the short throw DA, interface, and paper. This last job was a big red 66 Impala by the way. I dont have a ton of orange peel either, but I only paint a few a year at best.

Getting pig tails can be from dust nibs that the sandpaper picks up, try using some WET 1500 and 3000 grit Trizact on your hook and loop DA sander and it will probably be better. Sanding by hand takes too long and is way too hard, we reserve hand sanding for the tight spots.

Also you want to be sure that you sand enough with the finer grits that you remove the sanding scratches from the more coarse paper.


http://i1088.photobucket.com/albums/i340/autobodybasics/Con%20Con/Tip2a.jpg

gtome
01-20-2012, 11:12 PM
Yeah I always did 1500 wet, 2000 wet, and 3000 wet because they always seemed to load up on me if i didnt. And I still got the darn pigtails in it. Guess I need to keep at it.

Len
01-20-2012, 11:19 PM
Yeah I always did 1500 wet, 2000 wet, and 3000 wet because they always seemed to load up on me if i didnt. And I still got the darn pigtails in it. Guess I need to keep at it.

The pigtails can be caused by dirt that is coming from nibs in the paint you should use a nib file and/or small block to remove the nibs prior to machine sanding. For that purpose I use a FINE nib file and for runs I use a coarse nib file.


http://autobodystore.net/Merchant2/graphics/00000001/NibFile.jpg
LINK (http://autobodystore.net/Merchant2/merchant.mvc?Screen=PROD&Store_Code=ABS&Product_Code=S35260&Category_Code=PSH)

style
01-20-2012, 11:28 PM
I've been trying to figure out how to get rid of scratches after wetsand with 2000 grit wetsanding on fresh clearcoat (about 12 hours after painting) but still can't figure out why there are still scraches after polishing but my part is shinny.
Is 2000 grit still to harsh on the fresh paint? but I read most polishing compound will remove even 1200 grit.

sounds like maybe you piced up some dirt or debris,or possibly not enough water..


btw! KERRY your not a senator by any chance are ya?

autobodytech43
01-20-2012, 11:49 PM
if you don't keep the pad moist by spraying it down or don't use it with a low rpm it will pigtail. Gotta pay attention to it and check your pad. When it starts sticking to your substrate watch out. I notice when you wetsand by hand first and just use a da with a 3000 trizac it's never an issue cause you're not fighting orange peel and you're not on it forever.

gtome
02-01-2012, 07:18 AM
Yeah I tried it again, and I simply cant do it. After 3-5 short passes on fresh clear I get pigtails? So I just get at it with some 1500 wet, then 2000 wet..... both by hand, then take the 3000 trizac to it.

Len
02-01-2012, 08:53 AM
Yeah I tried it again, and I simply cant do it. After 3-5 short passes on fresh clear I get pigtails? So I just get at it with some 1500 wet, then 2000 wet..... both by hand, then take the 3000 trizac to it.

Question: Are you sanding by hand and getting pig tails? When hand sanding don't sand in circles sand in short straight strokes.

I've found that pig tails are normally caused by an orbital sander that traps dirt between the paper and the paint.

gtome
02-02-2012, 12:01 AM
No I only got pigtails when using the 1500 finish film dry. When i wet sand I use short straight strokes. Its funny you mention that because i have read that on here a few times before. but today i called the Sherwin Williams rep and he recommended I sand in circles. I told him I would not be doing that.

I read somewhere that the 3M purple disks are better and last longer. Any truth to that?

Len
02-02-2012, 07:59 AM
No I only got pigtails when using the 1500 finish film dry. When i wet sand I use short straight strokes. Its funny you mention that because i have read that on here a few times before. but today i called the Sherwin Williams rep and he recommended I sand in circles. I told him I would not be doing that.

I read somewhere that the 3M purple disks are better and last longer. Any truth to that?

Yes, 3M Trizact lasts much longer and you have less tendency to generate pigtails than you do with Finishing Film because the Trizact is used wet.


http://autobodystore.net/Merchant2/graphics/00000001/3m2088.jpg (http://autobodystore.net/Merchant2/merchant.mvc?Screen=PROD&Store_Code=ABS&Product_Code=3M2088&Category_Code=M3)

gtome
02-02-2012, 09:34 AM
Well....worth a shot I guess.

Len
02-02-2012, 09:52 AM
Well....worth a shot I guess.

Get some of the 1500 and the 3000 grit, you'll luv'em.

gtome
02-02-2012, 10:16 AM
Yeah I have the 3000 and its awesome. I hate to polish, so its been a real time saver. Its just the finishing film that screws me! I may try a little on a part of the hood again (the 1500 finishing film). Im curious how it reacts now that it has had more time to cure and the nibs are already out of it.

Len
02-02-2012, 10:50 AM
Yeah I have the 3000 and its awesome. I hate to polish, so its been a real time saver. Its just the finishing film that screws me! I may try a little on a part of the hood again (the 1500 finishing film). Im curious how it reacts now that it has had more time to cure and the nibs are already out of it.

The harder the paint gets the more difficult it is to remove sanding scratches but the 3000 grit scratches are so fine that they buff out pretty easy even from full cured urethane.

gtome
02-02-2012, 01:28 PM
Yeah i know thats SOP, but I was wondering if maybe this cheap clear didnt cure quite as quickly and that may be why I get pigtails so badly. but really I think this time it dried for over 2 full days before I touched it. That should have been plenty. Just trying to track down why im the only one that has this trouble.

Len
02-02-2012, 07:04 PM
Yeah i know thats SOP, but I was wondering if maybe this cheap clear didnt cure quite as quickly and that may be why I get pigtails so badly. but really I think this time it dried for over 2 full days before I touched it. That should have been plenty. Just trying to track down why im the only one that has this trouble.

Many less expensive clears never get real hard, that's one of the reasons why they tend to age more quickly.

gtome
02-02-2012, 11:17 PM
At $57 for a gallon kit...it doesnt get much more less expensive.