clear coat reacting with base!

[San Migweld]

I am using Lechler solvent metallic base coat but find if I apply a wet coat of 2k clear over it I am getting a reaction. This generally happens if I go on with multiple coats. I have tried long intervals between coats but still having problems.

Any advice from the wise please

 

[langy]

Sounds like the basecoat hasn't flashed off ???

 

[steveo3002]

very rare to get problems at the clearcoat stage , its usualy the solvent heavy basecoat that starts things off

more details on the prep please? any pics of the reaction

 

[San Migweld]

Hi there and thanks guys!

Prepped with 2k Lechler Hi build primer flatted with 800.

1:1 basecoat + thinner air dried.

No pics I am afraid as flatted out and reprimed but basecoat was shrinking and cracking I think due to the solvent in the clearcoat?

I am a hobbiest and not had these problems with other 2k base+clear systems.

How long should I leave between coats for basecoat to flash off please?

 

[steveo3002]

basecoat takes a matter of minutes to flash off , say 10-15 assuming you have reasonble temps

you probably should have stopped and let the first failed coat of clear harden up and deal with that rather than re prime

 

[langy]

Hi there and thanks guys!

Prepped with 2k Lechler Hi build primer flatted with 800.

1:1 basecoat + thinner air dried.

No pics I am afraid as flatted out and reprimed but basecoat was shrinking and cracking I think due to the solvent in the clearcoat?

I am a hobbiest and not had these problems with other 2k base+clear systems.

How long should I leave between coats for basecoat to flash off please?

Basecoat usually flashes in 10 mins depending on temp, I like to leave for an hour before putting on the clear.

How much thinner are you mixing in the clear ???

Just a thought but some basecoats thin 2-1, Is yours definitely 1-1 ???

 

[San Migweld]

Thanks Langy.

Yes just checked the data sheet which says 1:1 but says flash off can take up to 24hrs!!

Normally mix 10% thinners with 2k lacquer

Never had this problem before. I usually lacquer after 20 mins ok!

 

[steveo3002]

if its dried over so that you leave a thumprint , but your thumb isnt covered in paint its about ready

are you painting somewhere with decent heating?

 

[San Migweld]

Yes try to keep it nice and warm .

Maybe the cheap lacquer I am using is the problem?

 

[langy]

Thanks Langy.

Yes just checked the data sheet which says 1:1 but says flash off can take up to 24hrs!!

Normally mix 10% thinners with 2k lacquer

Never had this problem before. I usually lacquer after 20 mins ok!

I've never known a basecoat take more than 15 mins max