Clear coat ruined it

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dazthephot
Joined: Wed 09 Apr, 2008 18:58
Posts: 266

  Z3 roadster 1.9i
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Clear coat ruined it

Post by dazthephot »

All that hard work and I think I’ve knackered it with the clear coat.

Refurbing the mirror bases to fix the bubbled up galvanise. Rubbed down, two coats of acid etch, two coats of prime, two coats of colour all looking good. Get to the clear coat and on the second coat I dropped the mirror on one then got all manner of runs and bubbles. Gutted.

Can I wet n dry through to the colour coat to start the clear coat again or do I have to start from scratch?


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Gazza
Joined: Tue 04 Oct, 2005 20:58
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  M roadster S54
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Re: Clear coat ruined it

Post by Gazza »

If there is damage to the colour coat you will have to flat the clear and then do the colour coat again, then clear.
Gazza

"Understeer is when you hit the wall with the front of the car, oversteer is when you hit the wall with the rear of the car. Horsepower is how fast you hit the wall and torque is how far you take the wall with you"

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LaRy
Joined: Mon 12 Nov, 2018 17:47
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  Z3 roadster 2.8

Re: Clear coat ruined it

Post by LaRy »

I think you have to start it all over again! But my guess is that the color coats and the clear coat is not from the same manufaktur.

Or you waited to short time. Normally when spraying, wait 5 minutes between each spray layer, but wait 15 minutes between color and clear coat layer.
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dazthephot
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Re: Clear coat ruined it

Post by dazthephot »

Gazza wrote:If there is damage to the colour coat you will have to flat the clear and then do the colour coat again, then clear.
I suppose that’s the better option so will try that first.


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dazthephot
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Re: Clear coat ruined it

Post by dazthephot »

LaRy wrote:I think you have to start it all over again! But my guess is that the color coats and the clear coat is not from the same manufaktur.

Or you waited to short time. Normally when spraying, wait 5 minutes between each spray layer, but wait 15 minutes between color and clear coat layer.
I was sort of making it up as I went along. I left it 2 hrs between colour coat then left it overnight to dry fully. Then the clear coat I waited 1 and half hrs between first and second coat. The rattle cans all came from the same place but I suppose that doesn’t guarantee anything.


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dazthephot
Joined: Wed 09 Apr, 2008 18:58
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Re: Clear coat ruined it

Post by dazthephot »

LaRy wrote:I think you have to start it all over again! But my guess is that the color coats and the clear coat is not from the same manufaktur.

Or you waited to short time. Normally when spraying, wait 5 minutes between each spray layer, but wait 15 minutes between color and clear coat layer.
Lary

Are you saying spray colour coat then 5 minutes after another colour coat then 15 minutes later a clear coat before the colour has properly dried?


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Juvvajuvva
Joined: Sun 06 Nov, 2016 16:52
Posts: 87

  Z3 roadster 2.8

Re: Clear coat ruined it

Post by Juvvajuvva »

It needs to release the chemicals in the paint. The time is irrelevant. Some solvents can release weeks later.
The paint in all layers needs to be dry or it can fry.
Try putting on thin coats, you should only need a light coat of colour then one more to cover and the metalic stand up.
A light coat of clear, then keep touching the masking tape to see if it’s going, well, stringy.
That means you can put a heavier coat off clear on top.But don’t go mad, try to see it flow out and then STOP!
It can be harder to use cans than a gun.
The trick with painting is just, do it all again.keep practicing. Don’t bother trying to correct a big mistake, unless you are experienced and know how.
Instead you can get some fantastic tutorials on YouTube.
Good luck and Paint some Sh!¥ as the great Gunman says:)
LaRy
Joined: Mon 12 Nov, 2018 17:47
Posts: 149

  Z3 roadster 2.8

Re: Clear coat ruined it

Post by LaRy »

I read about this painting method and it has been working very good for me.

First, of cource, a good suitable primer and let it dry totally.
Then spray a coat of color, should just be looking wet, not very wet. Wait always exactly 5 minutes between each layer. Spray 4 layers like this.
Then wait 15 minutes before the clear coat.
Same principle again. 5 minutes between each clear coat layer, not more than it is just looking wet. Minimum 2 coats.

It is taking almost 1 hour, but the result will be very good. I've been using this principle for my mirror bases as an example. You cannot see any difference compared to the rest the car.
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dazthephot
Joined: Wed 09 Apr, 2008 18:58
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Re: Clear coat ruined it

Post by dazthephot »

Juvvajuvva wrote:It needs to release the chemicals in the paint. The time is irrelevant. Some solvents can release weeks later.
The paint in all layers needs to be dry or it can fry.
Try putting on thin coats, you should only need a light coat of colour then one more to cover and the metalic stand up.
A light coat of clear, then keep touching the masking tape to see if it’s going, well, stringy.
That means you can put a heavier coat off clear on top.But don’t go mad, try to see it flow out and then STOP!
It can be harder to use cans than a gun.
The trick with painting is just, do it all again.keep practicing. Don’t bother trying to correct a big mistake, unless you are experienced and know how.
Instead you can get some fantastic tutorials on YouTube.
Good luck and Paint some Sh!¥ as the great Gunman says:)
Thank you.


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dazthephot
Joined: Wed 09 Apr, 2008 18:58
Posts: 266

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Re: Clear coat ruined it

Post by dazthephot »

LaRy wrote:I read about this painting method and it has been working very good for me.

First, of cource, a good suitable primer and let it dry totally.
Then spray a coat of color, should just be looking wet, not very wet. Wait always exactly 5 minutes between each layer. Spray 4 layers like this.
Then wait 15 minutes before the clear coat.
Same principle again. 5 minutes between each clear coat layer, not more than it is just looking wet. Minimum 2 coats.

It is taking almost 1 hour, but the result will be very good. I've been using this principle for my mirror bases as an example. You cannot see any difference compared to the rest the car.
Thank you.


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dazthephot
Joined: Wed 09 Apr, 2008 18:58
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Re: Clear coat ruined it

Post by dazthephot »

As an update. I used 1000 grit wet sand to get through the clear coat. I did burn through To base metal in a couple of small areas but it’s all smooth. I’ll try with some thin layers of primer tomorrow then let it dry fully before a light sand with some 2000 grit to smooth. Then I’ll go for the colour and clear after. Two times a charm!


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