# Paint problem



## ST_Tarps (May 8, 2011)

Hi all

I sprayed my mini about 4 months ago when it was finished it looked really good i was really pleased with the results

here is a picture half way through wet sanding as you can see it doesn't look so bad









but this is what it looks like now









can any one tell me whats gone wrong as its starting to get worse.

Thanks


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## squiggs (Oct 19, 2009)

Give us some more info buddy.
What undercoat?
What paint?
What lacquer?
How was each stage dried?


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## ST_Tarps (May 8, 2011)

when i say i sprayed i mean me and my partners dad and he brought the paint just had a look at the tins, now we are no professionals and this is the first time we have done this
so forgive me if this makes no sense

undercoat - cellulose high build primer?
paint - 2k basecoat ?
ive no idea what laquer 
we left it in the garage to dry not sure what temp though

i probably should of got a pro to do it but i got quoted £2500


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## Tom-1 (Jan 23, 2013)

To me it lools like the colds got to it, but if you sprayed in december and dident get the area warm cpuld of cause this or really cold weather on fresh paint?


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## Tom-1 (Jan 23, 2013)

Cellose primer is absoulte cack only 1k 50/50 mix with thinners .no hardner so doesent really go hard


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## id_doug (Apr 6, 2011)

Hard to tell from the picture on my phone but is that not just bad wash marring?....


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## Franzpan (Mar 2, 2009)

I had a smart repair done on my wingmirror cap last October. It looked great at the time but now its gone exactly the same as yours. Its almost as if the paint is cracking under the laquer. Would love to know what causes this as well!


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## Mondeo220 (Apr 19, 2010)

Almost definitely a 1k lacquer used.

Caused by heavy application of coats with minimal flash off time. If the basecoat had insufficient time to flash off, this can cause the dry film to crack after a while. 1k is very brittle, after a period of time the layers of paint gas off and eventually the lacquer will crack like crazy paving.

It can happen with 2k lacquer but much rarer.

Celly primer is fine if left for 24 hours or baked with IR but only if the recommended amount of coats are applied, if its applied heavy, it will take ages to dry, as its not activated like a 2k.

Bascially the whole spraying process was carried out too quickly. To do a proper job, the whole lot needs to come off.


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## Tom-1 (Jan 23, 2013)

1k laquer? Aerosol? :s


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## Mondeo220 (Apr 19, 2010)

Tom-1 said:


> 1k laquer? Aerosol? :s


Yes 1k Acrylic, air drying, you can buy it in litres, 5 litres, doesnt have to be in aerosols.


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## ST_Tarps (May 8, 2011)

what would people recommend is the best kind of undercoat, base coat and laquer to use also how long between each coat to dry and at what temp?

thanks


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## robby71 (Jun 4, 2006)

Looks like this is the problem - http://pc.dupont.com/dpc/en/US/html/visitor/s/trouble/PDSG_Cracking.html


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## Andyb0127 (Jan 16, 2011)

Looks like a problem with the primer and basecoat reacting. Only cure for that strip back to baremetal start again.

Using.
Acid ecth primer on baremetal, only a light coat needed, as its an adhesion promoter for the high build.

2k high build primer.
Apply and mix as per data sheet. Do not rush between coats, allow to dry properly, around twenty mins between coats.

Basecoat colour.
Your choice either waterbase or solvent base. If its air dry again would be better of with solvent, again allow to dry between coats don't rush it.

2k hs laquer.
Again your choice which brand, depends how much you want to spend.
Apply as per data sheet and mix at correct mixing ratio.

Don't rush any of the prep work take your time with it as its the prep that will make the paint job.


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## Mondeo220 (Apr 19, 2010)

robby71 said:


> Looks like this is the problem - http://pc.dupont.com/dpc/en/US/html/visitor/s/trouble/PDSG_Cracking.html


As I said, incorrect flash times and excessive film build.


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## ST_Tarps (May 8, 2011)

Thanks all for your help i will try again.


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