1k Primer Sinkage Woes

[MyWifeIsHairy]

Hello,

I'm hoping you guys can give me a definitive answer to a sinkage problem I'm having with the roof of my car. I can't seem to find an answer to it.

The car was painted professionally in a water based base and clear but I did the prep and primer. I used a 1k primer over several areas of repair. I put it on far too heavily and didn't allow enough time between (several) coats for it to dry.

I now realise that this is the cause of the sinkage and now know what I should have done to avoid it / put it right.

My problem is this: The roof was primed around 1 1/2 to 2 years before topcoat. During that time I was aware that it kept sinking and I guide coated and reflated it several times. I then left it for several months with no further signs of sinkage, therefore I thought I had it beaten and all the solvent had evaporated. Unfortunately when the topcoat went on it was immediately evident again. The body shop, flatted and polished the clear coat and it was perfect. Five months down the line it has come back again.

My question is this: Will the 1k primer ever stop shrinking? It's been two years now!

Obviously there is a limit to how many times I can flat and polish it before I run out of clear coat.

Any help would be greatly appreciated!

Steven.

 

[steveo3002]

if its still doing it years after application then you might be stuck with it , you might find it gets worse when the summer sun gets on it

thats why time and time again we advise people against 1k products

 

[ajlelectronics]

if its still doing it years after application then you might be stuck with it , you might find it gets worse when the summer sun gets on it

thats why time and time again we advise people against 1k products

1K products INCORRECTLY applied I think you mean?

 

[steveo3002]

well it does sound like theres some prep /application problems

but i wouldnt advise anyone to use 1k products - 2k primer would have been fully cured in 48hrs and job done

 

[MyWifeIsHairy]

Thank you for the quick reply replies guys!

That's not good news but it is as I feared

I have used 1k (correctly applied) on other areas and it's been just fine. It's just the roof that I made a mess of.

Is my only option to take it back to bare metal and start again? Someone suggested that I put more clear on it and just keep flatting it but I'm not sure I like that idea.

Thanks again!

 

[ajlelectronics]

"but i wouldnt advise anyone to use 1k products - 2k primer would have been fully cured in 48hrs and job done"



IF you have the breathing equipment I agree. However, Cellulose products have been used commercially for a long time before 2K became available. Apart from incidents like Ford Blue Mink and Silver Fox self stripping, it has been a robust and reliable paint system that CAN be used by the amateur with realistic mask requirements. In my years, I have only had one failure. That turned out to be the paint shop selling me 2K primer instead of 1K. I didn't find out until three days later when the paint was still soft.

 

[ajlelectronics]

Is my only option to take it back to bare metal and start again? Someone suggested that I put more clear on it and just keep flatting it but I'm not sure I like that idea.

You can work on it all you like but until you bite the bullet and strip it, it will never be right.

 

[steveo3002]

was it original paint around the repairs ? might have been some kind of rubbish you primered over causing it

trouble with adding more clear ...the sinkage is the primer /old paint moving so eventualy the 2k clear will crack

 

[MyWifeIsHairy]

Hi Steveo,

Yes, it was original paint around the repairs.

What do you mean by rubbish? Are you referring to rubbish quality primer or what was already on the car?

As far as I am aware it was the original factory paint I painted over. I have owned the car for most of it's life and don't believe it's been repainted.

Thanks for the info on not applying more clear.

 

[MyWifeIsHairy]

Th

You can work on it all you like but until you bite the bullet and strip it, it will never be right.

I think that quote has just inspired me to get it back to a professional shop and get it done correctly.

Thanks for your help everyone!

 

[steveo3002]

id expect modern factory paint to take the repair , what i mean by rubbish - chips away type stuff , synthetic paint , bodged aerosol repairs etc

 

[MyWifeIsHairy]

I see what you mean now.

In this case I think it's just a case of me making a mess of it and not sorting it correctly before it went for it's top coat.

Lesson learnt