Technical chassis paintjob

I use Ospho to etch zinc plating before applying any primer. I've never had much luck just applying a coating primer/paint, to it without it being etched first.

 

I was a body man for over 60 years and I can tell you lead will not stick to sandblasted metal unless you you grind or wire brush it back down to shiny metal.

 

I send an e-mail to the company who blasted the chassis.
Waiting for an answer.

 

Por 15 will fill and stick.

 

Terrible crap if you ever want to get it off, & ugly too !

 

light sand blast (not to remove the galvanizing but to etch for adhesion)
may help cleaning with vinegar, a common household method for cleaning galvanize before painting
a self etching primer or epoxy may be used to help fill pits

 

Ppg product CRE would be good to fill the pits. Spray sand repeat.
Not sure how it will like fresh galvanized/metalized though.

 

If the pits aren't too deep, I'd just shoot a good epoxy, with filling qualities, like HOK's KP-2, 4-5 coats, block down til you hit metal. Repeat if necessary. It's advertised to be able to fill 36 grit scratches, though I hope no one does!

 

Sand with 80 grit on a DA and prime with an epoxy. Sand all surfaces thuroly, I use a sand able epoxy.

 

Thanks for your replies !

I've an answer.

I 've to clean the chassis with a metal brush to a "shiny" metal.
Then apply a filler reinforced with metal fibre.
https://restom.net/carrosserie-prep...159487.html?search_query=fill+metal&results=2

The paint is a duo component epoxy
https://restom.net/peintures-colori...ml?search_query=2092&results=15#/couleur-list

 

Yep, Allmetal I believe.