15 replies to this topic

[daniel_johno]

Ive been painting a few parts of my car that needed sprucing up. All the parts where rubbed down with 600 and 800 wet and dry, filled and primed where needed with UPOL 2K primer. The panels where then wiped with panel wipe and a tack cloth before the black basecoat was applied. The base coat was thinned with 2K thinners. There are small areas which look to have had a reaction. The area where the reaction occured was then rubbed down again and clean up, degreased, tacked etc and painted and the same happened again. It actually happened alittle worse the second time!

Id added some pics, Has any one seen anythign like this before or know why it is occuring. My dad resprayed his MX5 a few weeks back and the same thing happened on his last coat lacquer. All the rest of the paint was fine until the very last coat. He rubbed it all down repainted it and it was fine after.

Ive added some pics of the reaction. Could it be to do with the temperature we're spraying at?

Thanks

Daniel

[jack_marshall]

Not great pictures but it looks as if your basecoat is lifting the primer.

This can happen when the primer isnt fully cured or you have used too much thinner in your basecoat.

800 it back till you get down to good primer.. if needed reprime. Leave it overnight to go off, re flat then try again. Also try halving the amount of thinner your using in your basecoat.

[MarlonSpi]

i had this once..... it turned out that where i was painting in my garage, there was brake fluid in the atmosphere etc from where we had been doing mechanical work in the same shed. hope this helps..........

[jack_marshall]

The result of oils in the air is usually fish eye/silicone marks.. where as that looks like a common paint reaction.

[Surfbluegarage]

the primer used underneath wasnt etch by anychance was it... had this before when i didnt apply a high build or standard 2k primer over etch/zinc primer and had exactly the same affect.. its the etch thts causes it. that can also happen when like stated above the paint is thinned out/overstretched too much as the thinners reacts with the paint layer below it

[jack_marshall]

I've also had that problem over Upol etch.

Sounds like aerosol primer your using too.. even though it says high build 2k, its still very thin to come out the aerosol in a decent spray pattern.

[Surfbluegarage]

I've also had that problem over Upol etch.

Sounds like aerosol primer your using too.. even though it says high build 2k, its still very thin to come out the aerosol in a decent spray pattern.

me spinks its etch.... one thing tho.... how do you get 2k etch in a can????

[jack_marshall]

From what he says it just sounds like he is using that Upol 2k high build in an aerosol, called high 5 or something.. and although its 'high build' its still really thin so is likely to react if it hasnt fully cured or your putting very thin basecoat over it.

[Surfbluegarage]

aaahh i know the stuff you mean.. acid 8 by upol? yeah its only 1k that stuff.. *yellow human water* thin aswell lol. ya cannea get 2k in an aerosol as 2k its 2 parts which means you have to add activator/accelarator seperatly.. anythin in an aerosol is only 1k.. wish they did tho.. life wld be so easy... perfect finish in a can ay! haha awesome!

[daniel_johno]

Thanks for all the replies guys. The UPOL high build primer wasnt in an aerosol form it was applied with a spray gun. It was the 2K one you mix with a hardener.
Thsi stuff..... http://cgi.ebay.co.u...34.c0.m14.l1262

The reaction looks like crows feet. The primer was only sprayed friday night and then the black applied saturday morning and the temp was quite cold so maybe the filler hadnt set.
The panels where rubbed down more tonight and then repainted and it has still reacted alittle bit. Im now worried the same thing will happen when I spray the lacquer on tomorrow!!

Thanks again everyone

Daniel

[Surfbluegarage]

for some reason it wont happen with the laquer... good tip here i found out not long back... flat it back so its not proud of the service and laquer it... sounds mad i know but its actually insluates it.. then falt it back again really for ya base and reaply... 99% sure it wnt react again if you do that...

[jack_marshall]

Yeah I've done that before but using 1k as it goes off alot quicker. Could also try a 50/50 mix of hardener and thinner over it as a block.

[wassupcrew]

I've had this reaction before. it was due to the primer not being cured properly due to temperature, and time. i got around it by increasing the amount of hardener i used with the primer. it hardened lovely and had no reaction s

[joe90]

Its the thinner in the base coat that is corsing the problem. the thinner will be soaked up buy any paint that is not sealed properly (the primer. when you flatted the primer back was it clogging the papper? good sign the primer has not gone off)look what happens to a base coat when left to dry out in a pot (thinner evaporates) then add a spash of thinners you will see the same result. It crinkes up!
You can try & stop it buy trying to evaporate the thinners quicker, light application of base coat, pull the trigger half way. only air will come out over the painted panel which will make the thinners leave quicker.
This dose not happen with lacker because the thinner content is lower.
i am assuming you are not using water base.

[daniel_johno]

Thanks for all the responses.

We painted everything again today after rubbing it down and it all went on ok with no reactions so it must have been the primer underneath not being set. Lacquered it aswell with no issues so just the hard job of wet sanding it and buffing it up.

Thanks again

Daniel