15 replies to this topic

[trog1971]

Hi I've stone-chipped the underside of my car,it was applied over a zinc primer (painted when it was sandblasted) which was left to cure for about 10 days and was rock hard so applied a couple of coats of 2k top coat which went well but after 2 weeks I can still leave fingernail marks in it. Has something reacted or does it still need more time cure.my garage is not the warmest but I have had a heater on it in a polythene bubble.will this ever cure as the rest of the car will be done at a paint shop and baked.many thanks Trog

[minidaves]

after two weeks it should be solid no matter what

[Ben_O]

Stone chip should never go Hard. It's the soft rubbery finish that stops the stones from chipping.

 

If it went rock hard, then it would be susceptible to chips.

 

How soft is it?

[trog1971]

Hi ben it was rock hard before i applied the top coat and the paint appears to have dried but if i push my nail into it it will leave a mark.i used gravitex stonechip

[Ben_O]

Hi ben it was rock hard before i applied the top coat and the paint appears to have dried but if i push my nail into it it will leave a mark.i used gravitex stonechip

It's probably the solvents in the top coat have softened everything up. If it was a reaction, then you would expect to see pickling.

 

I would wait and see for now. It could take weeks for the solvents to fully evaporate and the paint harden

[STG95F]

Did you put the correct amount of activator in the 2K top coat ??

[trog1971]

Ok cheers mate,fingers crossed! Im wanting to turn the back upright so i can paint the interior but not sure weather to carry on
trog

[trog1971]

I done what the paint shop recommended. 2:1 and 10%

[matty1995]

hi there i used the same gravitex stonechip brilliant stuff provides a nice base, i then used 2k on mine and it dried fine, i have heard a few horror stories from a few pro sprayers who knew people that had mixed the brands of paint/hardener, by and chance was it a u pol hardener?

[STG95F]

sounds correct .  I had this happen once and it must of been faulty activator or paint ??  , i left it for about 2 weeks and it still never went off fully . right pain in the arse as i had to strip it all back off again 

 

As Matty said . some done mix well 

Edited by STG95F, 21 December 2015 - 09:19 PM.

[trog1971]

No it was churchill 2k premium extra fast air dry hardener supplied by rainbow paints as was the paint and thinners cheers Trog

[STG95F]

mix some more up and try on a small section of spare steel  without the stone chip and see if that goes off fully .  then you will know if it the stone chip at fault 

[matty1995]

well the 2k paint i used was the churchhill stuff had upol hardener all mixed correct, once the paint had cured i was then able to literally peel every bit of paint off back down to the primer, i had give it a good key as i did before primer, even the bodyshop said it was soulely down to mixing the brands bloody annoying when the paint was supplied as part of a kit :@ but hey ho!

[cal844]

well the 2k paint i used was the churchhill stuff had upol hardener all mixed correct, once the paint had cured i was then able to literally peel every bit of paint off back down to the primer, i had give it a good key as i did before primer, even the bodyshop said it was soulely down to mixing the brands bloody annoying when the paint was supplied as part of a kit :@ but hey ho!

Had this before!

[trog1971]

Ok did it ever harden or did u strip it back