PDA

View Full Version : Help: Removing clear bra line



Cvjeticanin
01-10-2015, 12:57 AM
After removing an old clear bra from a 2005 BMW M3 I noticed that it left an outline/edgeline on the paint.

I tried polishing & compounding but neither helped out. The paint looks great but the line is still there! I can't feel the line with my finger nail at all but it is definately visable and before trying to wetsand I wanted to ask you guys if anyone had this issue before?

Any advice will be greatly appreciated. I will try to post up some pictures tomorrow if I can caputure it on camera.

DBAILEY
01-10-2015, 04:44 AM
It could be a razor cut line from installation. I've seen that many times where the razor cut too deep. If its just stained from dirt then try a good paint cleanser to see if it pulls more dirt out than the polishes were able to abrade off.

swanicyouth
01-10-2015, 09:11 AM
If you tried to compound it already, I don't think a paint cleaner can help. Honestly, these lines can be difficult. The situation could be a few things:

1. Razor cut from clear bra installation if CB wasn't pre-cut.

2. Paint was polished to a significant degree after CB was installed.

3. Different UV fading of paint under / over CB area.

4. Some type of coating or "smart repair" on hood where CB was not.

Depending on the cause, WS may or may not fix it. I would invest in a $200 PTG before you start and wet sanding. BMW paint is quite hardy, but you want to know what your starting with (see #2). Your factory readings on a 2005 M3 should be in the 130-140 micron range if the paint hasn't been messed with too much. If that's the case, yr likely good to wet sand.

I'd compare measurements where the CB was and wasn't.

Cvjeticanin
01-10-2015, 10:22 AM
If you tried to compound it already, I don't think a paint cleaner can help. Honestly, these lines can be difficult. The situation could be a few things:

1. Razor cut from clear bra installation if CB wasn't pre-cut.

2. Paint was polished to a significant degree after CB was installed.

3. Different UV fading of paint under / over CB area.

4. Some type of coating or "smart repair" on hood where CB was not.

Depending on the cause, WS may or may not fix it. I would invest in a $200 PTG before you start and wet sanding. BMW paint is quite hardy, but you want to know what your starting with (see #2). Your factory readings on a 2005 M3 should be in the 130-140 micron range if the paint hasn't been messed with too much. If that's the case, yr likely good to wet sand.

I'd compare measurements where the CB was and wasn't.

I think in my case #2 is what i'm dealing with. I know the car has been compounded at least 2 times before and the paint under the Clear Bra hasn't been touched. I will try and take a pic of it and post it up later....but it's definitely not a razor cut. Like you mentioned I don't want to wet sand unless i measure the paint first.

cardaddy
01-11-2015, 03:35 AM
Had that problem before on soft Infiniti red and it WAS NOT a cut line. :(

Ended up taping out about 1" wide strip and feather sanding with a 1" piece of 2000 grit just along the line. Went outward in both directions ever so slight and overlapping at 45° angles both towards the windshield and towards the front of the hood.

Then buffed it out with Menz 1000.

That helped, didn't take it all out.

So I went back (didn't tape it back up the same). Taped up right up next to the line about a 1/4" wide strip and used 1" squares again but did 1000 grit. Tried to really concentrate the sanding in between the tape lines.

Oh.... used the 3M blue vinyl tape because paper tape would NEVER work for doing this.

Then pulled the tape and retaped a 2" wide strip. (With paper tape outside the vinyl tape.)

Used the Duetto and the Rupes sanding discs with a quick run of 2000.

Then pulled all the tape and went with the Rupes 3000 and worked out a full width of the disc down the whole thing.

At that point it was either be done with it or end up burning through the clear! :eek:

Didn't take but a minute to get the sanding marks out with Menz 1000 amd a Rupes yellow pad, followed by 4000 and the white pad.

If you look really hard.... you'll still see it. But it doesn't slap me in the face anymore like it did.

FWIW If I ever manage to put ppf on it again I'll probably just do the whole hood. ;)



Sent from my SAMSUNG-SGH-I337 using Tapatalk

allenk4
01-11-2015, 11:45 AM
Is reapplication of PPF out of the question?

That seems like the best solution

Cvjeticanin
01-12-2015, 06:47 PM
Thanks for the feedback guys! Unfortunately I decided to compound the line out and ended up burning through the paint! I'll make a new thread about the whole process with pictures. Hopefully someone else can learn something through my mistake!

allenk4
01-12-2015, 08:16 PM
Thanks for the feedback guys! Unfortunately I decided to compound the line out and ended up burning through the paint! I'll make a new thread about the whole process with pictures. Hopefully someone else can learn something through my mistake!

There is a thread for that:

http://www.autogeekonline.net/forum/tricks-tips-techniques/87443-oops-i-made-mistake-how-you-can-learn-me.html

Cvjeticanin
01-13-2015, 11:15 AM
Hey guys here is my update to this project that went horribly wrong for me.
http://www.autogeekonline.net/forum/auto-detailing-101/88256-hopefully-someone-learns-my-mistake.html#post1209112


There is a thread for that:

http://www.autogeekonline.net/forum/tricks-tips-techniques/87443-oops-i-made-mistake-how-you-can-learn-me.html

Thanks...I just made a new thread and I posted a link to it on your Mistake Thread as well.