Touch up Paint Questions and More for an Expert... - PeachParts Mercedes-Benz Forum

babtahi · #1 06-25-2002, 02:19 AM

first off i noticed i have some small bumps on the roof of my car directly to the rear of the sunroof... i have tried Maguires Scratch X to remove these with no success... Am I to assume that Claying will work and if so what exactly is that b/c i am new to all of this...

secondly i have some small chips of the paint on the hood of my car from rocks and other road debris... i bought touchup paint from my MB Dealership but no matter how hard i try it looks worse with the touch up then without it... do you guys have any tips on applying touchup to make it look as good as possible...

thanks for the help

this forum rulez...

brookspw · #2 06-25-2002, 09:58 AM

You have 2 options. Either wetsand and buff OR use the Langka system.

I have done both and let me tell you, Langka works!

brookspw

placo1 · #3 06-25-2002, 10:18 AM

brookspw,

The key to a good touch up paint application is patience. Mike from Meguiars explained the following to me which has worked for him.

1. Go to a hobby/art store and purchase the finest paint brush available. (The tip should be extremely fine)

2. Prep the surface of the chip by first using rubbing alcohol. Then create a point with a piece of very find sand paper (3000grit) and quickly and carefully sand the surface of the chip. Clean again with alcohol.

3. Use the fine paint brush and apply a very very VERY little amount of paint to the chip. The paint should be nearly see through. Move to the next chip. Once the car has been touched up once allow to dry (1 - 2 Hours) and apply a second coat. Let dry.....apply again.....let dry....apply again until the chip has filled in.

4. Depending on how careful you were you might need to wetsand the area were the chip is.....this is where I can't help you, I don't know the proper wetsanding procedure so I'll leave it do someone else to explain this.

I still don't know if I have the patience to do this but I think I'm going to give it a try in a couple of weeks.

brookspw · #4 06-25-2002, 12:55 PM

It was babtahi's question. I just replied to it.

brookspw

Mike Phillips · #5 06-25-2002, 03:11 PM

Touching up small rock chips is hard no matter what you use or who your are.

For the average person, using the factory touch up paint, you will increase the likelihood of your success, (success defined as filling in the chip area and making the paint look better than it did before), by NOT using the built in brush that comes with the touch up paint.

Most of the ones I have seen are HUGE. They glob on just a ton of paint, in the rock chip and around the rock chip. You end up with the rock chips filled in but only to be replaced with huge globs of touch-up paint.

If the touch-up paint doesn't match closely, then it may look worse than when you started.

The secret to doing it yourself is to go to an "Artists Supply" store and spending $3.00 on a "Fine" tipped paint brush and a small bottle of mineral spirits to clean your brush with when your finished.

Do the best you can to clean the rock chip area, wipe with wax and grease remover if you have some, isopropyl alcohol if that’s all you have, Dawn dish soap, etc. You want the paint to be able to "bite" into the rock chip area as best as it can.

Wiping the area with a rust neutralizer is a good idea too.

You can buy a rust neutralizer at any PBE store, (Paint, Body and Equipment) in small sizes for less than $10.00

I bought some of this just a few months ago when my wife and I prepped the sheet metal on her 1959 Cadillac. There were a few different brands, can't remember the names by I tried them all and they all seem to work pretty good.

You don’t want the sheet metal to rust under the touch-up paint. If you plan to keep your car for a long time, it will come back to haunt you.

If you can, scuff the rock chip with something abrasive, something to "rough" the surface up. Again the idea is to get the touch-up paint to bite, adhere or stick to the surface.

Then, after the area is clean, roughed up and dry… apply "THIN" applications of your touch-up paint.

Allow each coat to dry or at least "flash", (surface dry) before applying another application of touch-up paint.

Avoid getting it on the surrounding edges. You want to bring the level of the rock chip area "up" until it is level with the surrounding areas.

You do not want to end up with a big glob of paint protruding up on the hood of your car, let along a dozen of them or more.

If you just want to protect your finish, leave the level even or just a little below and call it good.

If you want to take to a higher level of quality, Meguiar's sells these little "Sanding Blocks". They are pure blocks of grit, available in a variety of levels of abrasiveness, starting at #1000 grit and going to #3000 grit.

You more or less use these to "block sand" the high points off of the filled in area.

After that, you could Machine buff.

I use the Meguiar's W-8006 yellow colored, polishing pad with some Meguiar's #2 Fine-cut Cleaner, followed by the Meguiar's W-9006 tan colored finishing pad with some #9 Swirl Remover and then go to wax.

To be fair, Mothers offers some type of Rock Chip Repair Kit. I haven't used it but the Press Release makes it sound pretty good.

Also, a lot of detailers and Paintless Dent Repair business offer this service, I think… You might find it to be worth your time to just pay someone else to do it for you.

I have always owned old Chevy trucks and 1959 Cadillac's. These are mostly all grill in the front, so chip problem hasn't been too much of an issue for me.

With only a few exceptions, I haven't done too much chip repair in my life. I have been asked a lot, but because it is so hard and time consuming, it's hard to charge for it. Plus… it's not even fun to do, so I opt out.

Hope this helps…

Mike Phillips

SSharma · #6 06-25-2002, 06:30 PM

Here's my touch-up suggestion:
First you need paper matches, a nick sander, touch up paint, clear coat paint (optional), blue masking tape, rubbing alcohol, 3000 grit wet sandpaper and sanding block, small bucket of water, swirl mark remover, and polish/glaze.

First clean the scratch with the rubbing alcohol. Put the blue masking tape around the scratch. Then make a few passes with the nick sander to clean any stuck on crap in the scratch. Wipe down the scratch with the rubbing alcohol again. Apply the paint with the back end of a paper matchstick. Don't brush it in, just kind of let it flow into the scratch. You'll need to build up layers, letting each one dry before you paint in the next one (at least 15 mins). Build up the paint so it's a little above surface level. Once the last coat of paint is dry (if you use clearcoat, it'll be the last coat), then wrap your 3000 grit sandpaper around your sanding block and dip it in water. Sand down the scratch to the surface level, keeping the sandpaper well wet. Once it's dry, use the Swirl mark remover. If that doesn't get rid of the sandpaper marks, you might have to use a Fine Cut Cleaner. Then polish. That's all ( :p ) there is to it.
For the claying, I suggest a Clay Magic bar. Instructions are on it, but basically you spray a lubricant on the car and rub the clay bar across it. Do sections at a time. Afterwards, I like to go over the car with the Meguiars Quick Detailer (that's the best spray bottle I've ever used).

Lee Scheeler · #7 06-26-2002, 06:18 AM

Without resorting to airbrushing and stuff you can't practically do at home the best way I have found for touch up paint work is as follows:

Use factory touch up kit paint ONLY

NEVER bother with the included brush unless you are painting the groutwork in your bathroom

get the area clear of wax and whatnot so the rubbing alchohol (following a good/normal wash) or even some windex will do the trick

work only in a VERY well lit area

apply with one of the following: artist's ultra fine brush, wife's similar makeup brush (warning: can get you sleeping in the garage with car), or my personal favorite....a box of toothpicks.

The toothpicks (wooden please) can be used once and tossed. You can use the tip or break them in pieces to use the even finer resulting "wisps".

When applying the paint take the least you think will work and use 1/2 of that. Don't fill up the chip completely. Touch up, move on....when you have done all the chips on the car give the paint an hour or two to dry (more if its humid). Rinse and repeat till you have 2 or 3 goings over done. By then the chip should be pretty well gone. You can try the wet sand thing if you feel you must, but more often than not you can do more damage than was there to begin with. So unless you have experience wet sanding, leave it touched up as described. If done well (read: slowly and precisely) it should get it back 90+% of the way.

Hope this helps,
Lee

Mike Phillips · #8 06-26-2002, 11:55 AM

Don't sand on you car unless you really feel you must.

It takes a lot of skill to wet-sand fresh paint let alone factory paint. In most cases, factory paint, because it was "baked" on at the factory is not only harder, it is also potentially thinner.

You could get into trouble real fast.

Been there, done that.

(Side note: Even though factory paints, especially clear coats are "very hard" at least compared to traditional lacquers and enamels, they are still easily scratched. The "hard" factor comes into play when you try to remove the scratch. It is hard to do because it is hard to "move small particles of paint" in a controlled way resulting in a smooth level surface.)

The basic problem is leveling the touch-up paint with sanding paper and NOT sanding on the surrounding area. Pretty hard not to do.

Then when you buff out your sanding marks, what you realy want to do is only buff, again, on the touch-up paint, and not the surrounding paint. Pretty hard not to do.

I agree whole heartedly with Lee, don't worry about sanding your touch-up paint, it will lead to more trouble than it's worth.

Get the chips filled in the best you can and "Drive it!"

Mike Phillips

SSharma · #9 06-27-2002, 09:56 AM

Quote:

Originally posted by Mike Phillips

The basic problem is leveling the touch-up paint with sanding paper and NOT sanding on the surrounding area. Pretty hard not to do.

Then when you buff out your sanding marks, what you realy want to do is only buff, again, on the touch-up paint, and not the surrounding paint. Pretty hard not to do.

Yes, that is a problem, which is why I use the blue tape. I tape off very close to the chip so I don't get the surrounding paint. Then when I use the Swirl Free Polish, I remove the tape and polish the area.
I'm no stranger to wet sanding, but I wouldn't say I'm an expert. So far I haven't had a problem.
I will try skipping the wetsanding next time and see how it turns out. If I can skip a step, then I can be done that much faster.

Hocky · #10 09-13-2002, 07:47 AM

I have watched these guys here who work on-call at car yards to fix stonechips on used cars readying them for sale. I noticed that they use special equiptment which look like giant syringes which hold the particular paint that they have mixed on the spot and fill the holes in the paint surfaces with it. The paint looks very thick like wax and fill the spots easily. A quick polish when its dry will almost cure the damage when observing from say 2 metres. Closer look will still show the damage which has been given a quickie fix! Maybe this effect will only last for a few weeks or couple of months before going back to the original condition.

afmcorp · #11 02-07-2003, 02:25 AM

hi

i'm reading all these posts and i understand and can agree with most all the information. but i have one question.

i am under the impression that mbz (in my case 87 & 88 420sel) have a clear coat finish. the part i don't quite understand is no one seems to be addressing the clear coat. i know on a straight enamel (no clear coat) sand, polish and buff you're back to normal. but what about the clear coat. after repair of the "colored" paint what do you do for the clear coat.

i have some surface rust on my 87 that i'd like to get out. but i don't need to paint the whole roof.

talk to me guys.

tks
craig

Lou K · #12 02-07-2003, 03:38 PM

I have tried all of the methods above. I have recently used the Langka system and it beats all of the above. Best of all it does not require the time that some of the fixes listed here, requires no sanding and the results are the best that I have ever experienced.