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Garage => Interiors & Exteriors => Topic started by: marku on 10 April 2018, 12:05 PM

Title: Paint
Post by: marku on 10 April 2018, 12:05 PM
I know that this has been discussed many times but I have forgotten. How many coats of paint were applied in the factory? Was recently cleaning off a panel and the number of layers was surprising. I know that the 116 had been repainted and not cleaned back to metal but that didn't account for the number of layers.
Title: Re: Paint
Post by: ptashek on 10 April 2018, 03:54 PM
Quote from: marku on 10 April 2018, 12:05 PM
I know that this has been discussed many times but I have forgotten. How many coats of paint were applied in the factory? Was recently cleaning off a panel and the number of layers was surprising. I know that the 116 had been repainted and not cleaned back to metal but that didn't account for the number of layers.

Primer, paint, clear (if metallic) - one of each.

Here's a sample of how the W124 was done:
https://youtu.be/OI1TJ-1aCZY?t=379

And here, a much newer C-class:
https://www.youtube.com/watch?v=Kamz8MA3DEw

The W116 may have still been sprayed by humans, but the process wouldn't have been much different.
Title: Re: Paint
Post by: marku on 12 April 2018, 12:08 PM
That it? One of each surely wouldn't give you the colour density? I would have thought that a car like the 116 would have had quite a bit of paint on it. I have been putting about 8 on because I have always preferred the colour to be really opaque and think a single coat a bit thin.
Title: Re: Paint
Post by: ptashek on 12 April 2018, 05:09 PM
Quote from: marku on 12 April 2018, 12:08 PM
That it? One of each surely wouldn't give you the colour density? I would have thought that a car like the 116 would have had quite a bit of paint on it. I have been putting about 8 on because I have always preferred the colour to be really opaque and think a single coat a bit thin.

That's it, but a single layer laid by a factory robot can't be compared directly to one sprayed by a human. Different process, spray pattern, paint flow etc.
Still, factory paint with all the layers is ~150µm.

Spraying by hand gives much thicker layers. For comparison, the first KTL primer layer on my car is around 35µm, as it's deposited via cataphoresis. But the rest was sprayed by hand, and the layers total well north of 300µm. The issue is that if you overdo it, you loose detail and there's trim fitment issues. More isn't always better :)
Title: Re: Paint
Post by: s class on 13 April 2018, 06:59 AM
Quote from: ptashek on 12 April 2018, 05:09 PM
The issue is that if you overdo it, you loose detail and there's trim fitment issues. More isn't always better :)


I agree totally.  It looks grotesque when so much high-solid primer/surfacer has been used that the body lines become dulled. 

I do a lot of painting and I try to maintain the absolute minimum film build.  I spray Standox VOC basecoats, and typically I put the first coat on partially wet, and that provides only a tinting of the surface.  THe second coat is full wet, and generally almost complete opacity is then achieved.  Third coat is again full wet.  THe clear that follows, I apply as two full wet coats.  That is plenty enough to allow for thorough colour sanding. 

For both the base and clear, I apply more reducer than the VOC spec calls for, so that the coats go on thinner and smoother. 
Title: Re: Paint
Post by: daantjie on 13 April 2018, 11:10 AM
Quote from: s class on 13 April 2018, 06:59 AM
Quote from: ptashek on 12 April 2018, 05:09 PM
The issue is that if you overdo it, you loose detail and there's trim fitment issues. More isn't always better :)


I agree totally.  It looks grotesque when so much high-solid primer/surfacer has been used that the body lines become dulled. 

I do a lot of painting and I try to maintain the absolute minimum film build.  I spray Standox VOC basecoats, and typically I put the first coat on partially wet, and that provides only a tinting of the surface.  THe second coat is full wet, and generally almost complete opacity is then achieved.  Third coat is again full wet.  THe clear that follows, I apply as two full wet coats.  That is plenty enough to allow for thorough colour sanding. 

For both the base and clear, I apply more reducer than the VOC spec calls for, so that the coats go on thinner and smoother.

Ryan what is the going rate in ZAR for a full body respray?  Here in Canada you can easily drop 10K on a job and trying to find a shop which gives you true value for money is impossible.
Title: Re: Paint
Post by: marku on 15 April 2018, 10:50 AM
The body lines are not that sharp are they? I can't imagine getting that much paint on to give that effect. As a total amateur, I have never painted a car before never mind the size of the 116, and I am quite paranoid about getting runs so if anything I tend to put too little on each time and rely on building it up with successive coats. Quite pleased with the finished work though. I did put two coats of primer on the first being quite heavy but it is flatted right back to the metal. I have found this the easiest way to fill the numerous scratches left by someone who used a disc sander previously to remove paint. They then used the thickest primer filler coat that was really difficult to get off. I put four coats of colour on but again I probably put too little on each coat and each is flatted down with the exception of the finish. Also two coats of clear with which I have had lots of problems but again is flatted down and this time polished which works really well. The way I am doing it is entirely my own but it solves the problems I have run up against. I have seen professional spraying being done and there is no way I can get that volume of paint on. I have tried and I have had to start again back to metal. It may not be the proper way but it is my own and it works for me. It has really been frustrating at times but I am pleased with the result and I would say that I am very particular and despite the hard work I have got a lot of pleasure in doing it.
Title: Re: Paint
Post by: ptashek on 15 April 2018, 04:12 PM
Quote
if anything I tend to put too little on each time and rely on building it up with successive coats. Quite pleased with the finished work though. I did put two coats of primer on the first being quite heavy but it is flatted right back to the metal. I have found this the easiest way to fill the numerous scratches left by someone who used a disc sander previously to remove paint. They then used the thickest primer filler coat that was really difficult to get off. I put four coats of colour on but again I probably put too little on each coat and each is flatted down with the exception of the finish. Also two coats of clear with which I have had lots of problems but again is flatted down and this time polished which works really well.

Sounds like a good approach. A few thinner coats are certainly better than a blob of paint dumped in one go.

My 280TE will be my own battle ground. Got no budget left to pull-off another Goldie, so it's back to getting dirty myself :D
I've seen it done and had the process explained to me many a time as a teen, but have never sprayed a car either.
Title: Re: Paint
Post by: rumb on 15 April 2018, 07:49 PM
I've started doing body work and painting 45 years ago and have painted about 7 cars so far.  There are a lot of good videos on every part of the process. As you probably heard prep is 90% of the job.  lots of sanding.....  For the 6.9 though I will probably do everything up to the final 600grit sanding and then hand off the top coat.  5 years ago I did a complete bare metal restoration of my 72 MG Midget in 7 month.  That was way to fast for me now.  But that car is tiny and simple compared to a W116.
Title: Re: Paint
Post by: marku on 17 April 2018, 12:49 PM
It was a bit intimidating at first and I despaired of ever getting through it as although knowing in principle how to do it had never done the practical. Finally came to terms with the work but accepting that it was going to take as long as necessary with no time frame for completion. Just a matter of working through it. As I said pleased with the finish and colour although it is a bit brighter than the previous but don't mind that only got to put everything back.
Title: Re: Paint
Post by: irvine on 23 April 2018, 05:17 AM
While we are on the paint subject, regarding the original paint was the w116 painted with clear coat after painting?
I'm looking for a specific polish and need to find out
Title: Re: Paint
Post by: ptashek on 23 April 2018, 07:16 AM
Quote from: irvine on 23 April 2018, 05:17 AM
While we are on the paint subject, regarding the original paint was the w116 painted with clear coat after painting?
I'm looking for a specific polish and need to find out

All metallic paints had a clear coat.
Title: Re: Paint
Post by: irvine on 23 April 2018, 07:58 PM
Quote from: ptashek on 23 April 2018, 07:16 AM
Quote from: irvine on 23 April 2018, 05:17 AM
While we are on the paint subject, regarding the original paint was the w116 painted with clear coat after painting?
I'm looking for a specific polish and need to find out

All metallic paints had a clear coat.

My car has Papyrus White any ideas if it's metallic paint or if it would of had a clear coat??
Sorry I don't know much about paint.

Cheers,
Neil.
Title: Re: Paint
Post by: TJ 450 on 23 April 2018, 08:23 PM
Papyrus white will be a single stage, so no clear should be used. It's far easier to work with and there is less to go wrong as compared with clear over base coat.

There won't be any problem cutting that back to restore the finish.

Sometimes though, if the paint is not original, I have seen clear coats applied to solid colours, so that's something to look out for.

Tim
Title: Re: Paint
Post by: irvine on 23 April 2018, 11:39 PM
Thanks for your the info.

Neil.
Title: Re: Paint
Post by: marku on 24 April 2018, 01:05 PM
Thought all Mercedes had a clear coat. Certainly gives even non-metallic paint that extra finish.
Title: Re: Paint
Post by: marku on 24 April 2018, 01:13 PM
Forgot to say that I did mechanically polish the clear coat mainly because I had such trouble with it. I could not get a coat free from "orange peel". It polished up really well using Farecla. The final finish is hand applied.