Answer need asap please

tcawley29

Hi,
I sanded down a square section of my roof to remove a rust patch. I then put primer on it, painted over it with colour match paint and put a coat of lacquer on it. Came out well apart from one problem. When it rains the square of lacquer shows up quite obviously, and also appears like its rain repellant. Any tips on how I can blend this in with the existing paint work. The car is a 2006 blue corolla with the paint in practically factory condition.
Thanks
Update see further down

colm_mcm

how big a square are we talking here?

tcawley29

colm_mcm wrote: »

how big a square are we talking here?

roughly 2 inches by 1.5 inches or else 3 x 2

tcawley29

seem to have sorted with a bit of t cut. the paint is slightly higher around the edges though. only by 1mm at most. how could i blend this best. possibly even strip it down seeing as it is just the edges.

Del2005

tcawley29 wrote: »

Hi,
I sanded down a square section of my roof to remove a rust patch. I then put primer on it, painted over it with colour match paint and put a coat of lacquer on it. Came out well apart from one problem. When it rains the square of lacquer shows up quite obviously, and also appears like its rain repellant. Any tips on how I can blend this in with the existing paint work. The car is a 2006 blue corolla with the paint in practically factory condition.
Thanks

Are you using a solvent paint or water based? All recent cars are water based paint and solvent paint won't match.

You'll have to sand back the lacquer and an biggish area around the patch you painted then mist the blue paint out. If there's a panel gap you'll need to do the same on the other panel also. Then lacquer again. Are you sure you've got the correct colour match?

colm_mcm

Wow, that's big enough, how come it rusted? The car would have been inside it's anti-perforation warranty.

Maybe polishing the whole roof area would do the trick?

tcawley29

Del2005 wrote: »

Are you using a solvent paint or water based? All recent cars are water based paint and solvent paint won't match.

You'll have to sand back the lacquer and an biggish area around the patch you painted then mist the blue paint out. If there's a panel gap you'll need to do the same on the other panel also. Then lacquer again. Are you sure you've got the correct colour match?

Not sure. I use cellulose. The colour is a very good match. Just have to level it now. I used t cut to help it match. Whats the easiest way to remove the 1mm high edges. I was thinking of using acetone again. its a mild blend so it only removes the new paint with a bit of elbow grease.

tcawley29

colm_mcm wrote: »

Wow, that's big enough, how come it rusted? The car would have been inside it's anti-perforation warranty.

Maybe polishing the whole roof area would do the trick?

the area was about 2cm by 1cm bubbled around. noticed the roof was covered in small scratches after i bought the car. was sold by a dealer for an 80 year old man. i assume the paint was bubbled due to a poor touch up job by someone. I painted a bigger area because i figured it would be easier to handle for my first time pinting a car. the t cut blended the colour well. nearly a perfect atch now. just want to remove the 1mm edge where the paint pooled against the tape. whats the easiest way to do so. i was thinking very mild acetone. thanks

Del2005

tcawley29 wrote: »

Not sure. I use cellulose. The colour is a very good match. Just have to level it now. I used t cut to help it match. Whats the easiest way to remove the 1mm high edges. I was thinking of using acetone again. its a mild blend so it only removes the new paint with a bit of elbow grease.

Stop your mixing paints. You'll never get it to match. Cellulose is solvent based paint and your car is water based.

Edit/

Water based paint needs an oven to cook it off, so you'd need to hire a heat lamp if you wanted to do it yourself.

tcawley29

Del2005 wrote: »

Stop your mixing paints. You'll never get it to match. Cellulose is solvent based paint and your car is water based.

Edit/

Water based paint needs an oven to cook it off, so you'd need to hire a heat lamp if you wanted to do it yourself.

the guy in halfords said it would watch. he was right. matched very well. im on about the edge from the raised cellulose. think i'll give the acetone a shot. either than or wet/dry paper.

Owen

Okay, lots of odd information on this thread. It's possible to mix different types of paint and still have a colour match. What you've done is a classic rookie error and hoped just to paint the affected area and lacquer a masked off area in the hopes of blending the paint. Short answer, you can't.

You need to sand it all smooth, paint the affected area again feathering the paint out at the edges of the repair, and lacquer the entire panel.

tcawley29

Owen wrote: »

Okay, lots of odd information on this thread. It's possible to mix different types of paint and still have a colour match. What you've done is a classic rookie error and hoped just to paint the affected area and lacquer a masked off area in the hopes of blending the paint. Short answer, you can't.

You need to sand it all smooth, paint the affected area again feathering the paint out at the edges of the repair, and lacquer the entire panel.

was afraid someone was gonna say lacquer the entire panel :P oh well, ya live ya learn.
would i really have to sand down the existing lacquer i put on since it's very, very light. applied via touch up pencil :L should i buy the 300ml or 500ml lacquer can from halfords
Thanks to everyone for ye're replies

Owen

Yes, you'll have to sand down the lacquer, you've already said it has a hard 1mm edge. If you're sanding any panel, always use a flat block with the sandpaper. The lacquer from Halfords is pretty crap, but if you're intent on doing a DIY job, there's no real way to get a good finish with aerosol lacquer anyway, so belt away.

corktina

sounds to me as if the 1mm higher edges are as a result of masking the area. You may need to re-do it sanding a bit larger area down to flat and then spraying without masking over an even larger area in order to feather the edges in. Then you'd need to compound it down (and then maybe lacquer the whole roof) to get it to blend in seamlessly.

Owen

Don't use compound, it won't blend, and it'll have an additional issue that the unseen residue from the compound will stop the paint from adhering, so the first time you power wash the car later, the paint will strip right off.

Just sand it flat with a block, degrease it with panel wipe, paint, lacquer.

... OP, I'd leave it alone, you don't want to be messing about anymore with the roof of a 2006 Corolla seems as the area effected is only an inch or two big, better to have that not 100% than have the entire roof dodgy looking.

tcawley29

Thanks for all the advice everyone. I sanded down the affected area alone again. repainted it with 2 coats of base and 2 coats of aerosol lacquer. much much better results so far, just not quite 100%. the new paint looks a bit darker than the old. is there any way i can fade this to bring it just that bit closer to matching (bit of a perfectionist).
Thanks a million guys