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laldog
08-21-2010, 07:49 AM
I finished painting my car 2 days ago and cleared it with PPG Ceramaclear. The guy at the auto store told that for a few bucks more I'd have a more durable finish, (resist scratching)

He did warn me that this stuff would be a little harder to sand, and I am finding out the hard way.

I just finished the front half of the car, and I didn't come close to knocking down the orange peel.445344544455

A few questions:

I don't plan on "showcasing" this car, but I want it to look good and like I know what I'm doing, is there an acceptable level of orange peel ?

If I don't sand out all the orange peel, am I wasting my time getting 1/2 of it knocked down?

If I started with 1000 (wet) will the subsequent sandings of 1200 , 1500 and 2000 also knock down the peel or do they just eliminate the sand scratches from the previous sanding ?

Lastly, can the 3M Finishing Film, since it was intended to be used dry, be used on say an electric DeWalt Random orbit sander that was intended for woodworking?

So many STUPID questions, so little time....

Thanks in advance.

Len
08-23-2010, 03:43 PM
If I started with 1000 (wet) will the subsequent sandings of 1200 , 1500 and 2000 also knock down the peel or do they just eliminate the sand scratches from the previous sanding ?

You eliminate the peel with the first sanding then you remove the scratches with the following grits. In cases where the peel isn't too bad you can start with 1500. We usually finish our sanding by wet sanding with 3000 grit Trizact.

The electric sander may or may not work depending on the action of the pad. It's normally recommended that you sand with a sander that has a 3/32" action but you can get away with 3/16" if you're careful.

Serge
08-23-2010, 05:44 PM
Its hard as helll...Did you try getting the shine back with a polisher? Its a hell of a job in a ceramic clear coat if you scratch it too deep...Do some small tests before you sand the whole car...

You dont have to remove all of the op for a car to look great. It will have a more factory look if you leave some on...

What are you using as a polish?

laldog
08-24-2010, 03:01 PM
I've already started wet sanding the clear. I did the entire car with the Ceramaclear, but a few sections came out with less clear than others.

A few of the rougher sections I started with 800 wet, and even with that couldn't get out all the orange peel, and of course, with such an agressive approach, had a few spots where I sanded through the clear.

The other parts of the car I started with 1000 and have it pretty close to peel-free.
It's not going to be fun, but I've spent summers around the house doing a lot less enjoyable tasks (mixing 20 yds of concrete by hand)

My approach at this point is to wet sand the entire car with 1000, 1500 and then 2000.

Polishing will be another story. I'm sure my guy at the auto body supply store will have a recommendation, usually a 3M product.

I'd rather continue wetsanding rather than using a buffer, but I'll cross that bridge when I come to it. I imagine that by the time I'm finished wet sanding, the cold weather will be here and I'll have to get intimate with my snowblower instead.

Thanks for your help. I can't imagine I ever successfully painted a few cars before this board was in existence.

What a great resource.

Serge
08-25-2010, 08:12 AM
With the bad advice he gave you to date...I doubt he will be more helpful with the polishing part.

The problem with the counter people in those places is that they never sprayed a car in their lives. They hire them I don't know where and then if they are lucky their bosses send them to a specific ppg course for counter people...which is not the same certification course we get as painters...

He should never have recommended this clear to you...its not a clear that is easy to use by any means and its difficult to repair. Imagine, the sand paper companies even have special sand paper for those classes of clear coats they are so hard....its an awful suggestion he made to you and I hope you don't get discouraged by this clear...I swear its not usually that difficult....even I hate those ceramic/anti graffiti class products...I just wont put them on anything but a dump truck or a trailer...

If you ever recoat it, make sure there is not shiny spot left...nothing will stick to this clear if its not well sanded...

Robert
08-25-2010, 09:13 AM
putting ceramic in clear to make the clear more scratch resistant, but the world being what is still finds a way to scratch it. Then, it's impossible to repair. If you manage to cut into the ceramic, get an abrasive hard and sharp enough to make the cut in the first place, that cut in the ceramic will be amazingly hard to get out.

The best idea is to sand that car down to no shine at all and re-clear. Use something suggested here - these guys know more collectively than any paint store counter person could know.

Robert

laldog
08-25-2010, 10:38 AM
I'm having mixed results using 3M Imperial wet/dry sandpaper, making sure the paper is changed often. It's not unworkable, and I just assumed the extra work involved in sanding this clear was a worthwhile tradeoff, increased durablilty for a little extra elbow grease.

The guy at the counter was very direct and clear that this product would be a little harder to work with, and I thought the extra work was worthwhile.

As I work, I've managed a few sand throughs in the clear and color. It has been suggested to lay down a coat of clear before i re-shoot the color to prevent the lifting problem I experienced before.

Is this accurate? I huess I'll use up my Ceramaclear for this and use a little more compatible clear.

Does this sound workable??

Thanks.

silentdub
08-27-2010, 09:33 AM
The best idea is to sand that car down to no shine at all and re-clear. Use something suggested here - these guys know more collectively than any paint store counter person could know.

Robert


Since you are probably tired of sanding, maybe you can pick up a gal of SPI Clear. I saw a car with it and it looked amazing, they didn't even sand/polish it. I ordered a gal for this 84 cabby. The price was fairly low compared to some of the stuff out there.

laldog
08-27-2010, 05:01 PM
Thanks for the help/suggestion.

I've been warned/advised to never, ever spray again until all the orange peel is sanded out.
Spraying over the orange peel only serves to compound the problem.

Personally, I remain hopeful that a new coat of clear (maybe thinned with a little reducer) would fill in the low spots and kind of "fill" the orange peel, but I think that is wishful thinking.

I'm going to work like hell to sand out as much as the peel that I can, put down a coat of clear (to prevent lifting), another coat of color, and then bury it with a PPG clear that is little more user friendly.

I'm sure the SPI is a great product, but the choice of clear coat isn't my problem. I think it's more my inexperience with the gun.

Thoughts??

Serge
08-27-2010, 10:53 PM
PPG DCU2021 or DCU2002 are nice user friendly clears....the omni clears are good choices too in a value brand. They lay down well, sand and polish easily...