How long to top coat primer

[ronan]

How long do i have to wait for 2 pack epoxy primer to dry before i paint it ?

 

[RaceDiagnostics]

I put on my lechler 2k high build onto lecher epoxy after an hour.

 

[langy]

How long do i have to wait for 2 pack epoxy primer to dry before i paint it ?

I usually wait an hour but if I remember right the spec sheet says a lot longer window is available

 

[RaceDiagnostics]

I don't really understand the lechler data sheet for this.

It says for wet on wet cycle 1 to 24 hours, and for dry on dry after 8 to 10 hours, how can that be?

I guess I don't understand exactly what wet on wet and dry on dry means.

 

[Maxakarudy]

I would wait at least 24hrs if air dying, shorter if you force dry. Epoxies skin over in a few hours, but don't dry/harden thoroughly for a couple of days at garage temp. Once you've epoxied, use 2k filler primer for preping as they dry quicker.
Martin

 

[ajlelectronics]

I would wait at least 24hrs if air dying, shorter if you force dry. Epoxies skin over in a few hours, but don't dry/harden thoroughly for a couple of days at garage temp. Once you've epoxied, use 2k filler primer for preping as they dry quicker.
Martin

And then you negate all the benefits of the epoxy. If you need more thickness, then laying additional epoxy coats has to be more sensible than laying a different and potentially inferior product.

 

[ronan]

Some of what i was spraying was cast iron fork yolks etc, which being cast is pretty rough. I've found the epoxy is thick enough to cover the pits and dings pretty well.

 

[langy]

I would wait at least 24hrs if air dying, shorter if you force dry. Epoxies skin over in a few hours, but don't dry/harden thoroughly for a couple of days at garage temp. Once you've epoxied, use 2k filler primer for preping as they dry quicker.
Martin

If you do that you need to rekey which negates the idea of wet on wet

 

[Maxakarudy]

And then you negate all the benefits of the epoxy. If you need more thickness, then laying additional epoxy coats has to be more sensible than laying a different and potentially inferior product.

I take your point about the quality of an epoxy primer, but if you are filling & blocking down panelwork to get really straight panels, then that's what filler primer does best, epoxy doesn't block down as well as 2k primer.
The purpose of epoxy is to act as a water resistant barrier on top of the metal that's all.
Everybody has their own methods & criteria, this what works best for me.
Martin

 

[ajlelectronics]

Don't agree. Epoxy blocks down beautifully and has a good build. As far as I am concerned, the fewer different materials the better.

 

[Maxakarudy]

You say filler primer is inferior to epoxy, explain why?

 

[RaceDiagnostics]

I would wait at least 24hrs if air dying, shorter if you force dry. Epoxies skin over in a few hours, but don't dry/harden thoroughly for a couple of days at garage temp.

Depends on the brand of epoxy, I have found Jotuns 101 and 87 are slow curing whereas Lechler is fast curing.