# Primer shrinkage??



## jetbox (Jul 12, 2009)

Hi,

I painted the roof of my car a few months ago following the below procedure..

1. rubbed down. back to bare metal only in places. to remove stone chips along front edge and various blemishes etc.
2. etch primer on bare metal areas
3. 1k high build primer. 3 coates
4. rubbed down again
5. reprimed areas that were thin from previous rub down
6. 1 k base coat
7. 1 k laquer 

I then left for a month before wet sanding and then polishing. It came up to a nice mirror finish and looked a decent job. But now a month later in the right light i can see areas where it looks like I can see signs of what it looked like at step one. You can see where there was original paint and where it had been rubbed back to bare metal. Difficult to explain and it does not show in photos. To me it appears that the paint has shrunk or soaked in to the original base. is this possible?

Now I can wet sand again and polish to refine but this is probably my last chance due to the available lacquer thickness. Will this continue to happen again? And how do I prevent this happening with future paint jobs?

many thanks


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## mr paint (Jul 11, 2009)

sinking is usually 


Too heavy coats 

not enough flash time 

too cold 

poor products


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## jetbox (Jul 12, 2009)

Thanks.

Could be any of those I guess apart from the poor products as I think it was decent body shop paint.

Ok, how do I recover. When will it stop sinking? Should I leave a lot longer before wet sanding again?


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## mr paint (Jul 11, 2009)

get some heat on it flatten with 240-320 past the repair /primer area then prime with a good quality 2k primer ...bake...or leave for a day or 2 then flatten wth 320 /500/800 paint and clear 




tommy


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## DEEJAY (Sep 6, 2008)

agree with the above, this is the method i normally use, depending on the repair area,


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## craigeh123 (Dec 26, 2011)

I've had the same happen to mine . 
All due to not 2k priming it


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## jetbox (Jul 12, 2009)

thanks all for replies.

So when will the primer stop sinking? It can not keep doing this surely. I plan to leave for a couple of months and then wet sand again.

Is there a technique that will work with 1k. I don't have the second compressor and airfed mask etc to paint with 2k.

There must be a method that will work ok with 1k??

thanks


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## Andyb0127 (Jan 16, 2011)

Another method instead of flatting the stonechips back to baremetal.
Use upol dolphin glaze it's a very fine liquid filler. Mix it up as normal filler, then the stonechips get a tooth pick and dab it into the chip making sure it sits a little higher than the chip, leave it to go off.
Then with a block and some P800 wet flat it until dolphin glaze is level and even, job done, then you can apply a couple of coats of primer over it, and flat as normal this way you Wont get any sinkage.

Unfortunately with 1k products it will sink as it has, but problem being you can flat and polish it but after a while I would say the sink marks will appear again. Or it could be the way you have blocked it causing a shallow which is what's showing in your paint.

Here's a link for dolphin glaze.
http://www.google.co.uk/url?sa=t&so...2qSzBw&usg=AFQjCNG7F_ngMgQWWkwR9lcnLJdl5OKJyQ


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