Hey y'all, what do you guys use to get paint to stick to cast metal parts? I cleaned them with alcohol first, but the Tamiya primer is coming right off with my nail.

Anyone use self etching auto primer on these style parts? I think they are zinc.

Hooben T-55 metal bits.

Hi, What paint do you plan using? Acrylic or Enamel?
Before I put anything on the metal, I first of all give the surface a very good clean with an Acrylic thinners.
Next I use Mr Hobby Metal Primer on all the metal on my builds before I paint on an Acrylic undercoat then finishing with an Acrylic top coat,
It works for me but others might have another idea or two.
Shaun.

I use 'Adhesion Promoter' by Dupli-Color. An 11 ounce can is under 6 dollars at automotive parts stores.

Sprays on clear like Tamiya metal primer, dries faster and I think is the best without going to an expensive etcher primer... especially on smoother surfaces. Of course, I still prep them with a light scoring of wet sand paper.

Much less expensive $$ and you get more than twice the amount. Will work on plastic as well.




Jeff

I am using acrylic paint. I have a little one and even with a paint booth/fume hood you can't be too careful.

I guess I didn't use a metal specific primer or an adhesion promoter.

Thanks guys!

We ALL need to be careful no matter how old we are. I can't even use super glue anymore without first masking up and exhausting the fumes.

The primer I use works with any paint, when allowed to dry properly.




Jeff

Jeff, you can skip the mask, just keep the exhaust going with CA. Masks filter organic vapors, CA is the from a family of isocyanates, same as expandable foam or urethan resin. There's no respirator that filters it (they've been researching for decades). The closest thing is using a wet filter pad which binds the iso before it gets to bind with your lung moisture.

If you're experiencing tightness in your nose and throat when using CA, that's what's happening. People get sensitized over time, so it may not bother you for years of use, then all of a sudden it does.

Not writing to scare you, just to let you know there's no need to put of a respirator. Pulling air past it and away is enough in the small levels in CA and it'll readily bond with atmospheric moisture. I have a friend who spilled it in a lab, left it for the hazmat crew. By the time they cleaned it up, a specimen aquarium in the lab had a solid plastic crust on the surface.

Solvents like lacquer thinner attack the brain, liver, etc, the same as alcohol but on a much more dangerous level. Isocyanates don't, they just bond with moisture and crystallize. The problem arises when that crystallization is in your lungs.

I have a powerful booth set up to keep me out of the airstream when casting resin, but with measuring and stuff, I occasionally get close to it. If I'm doing a lot of production, running the molds on the hour, I'll start getting the tightness in my sinuses by the end of the day.

Thanks to you Jeff, my eyes had been opened after our conversation on this topic a while back with your past experience. I wear a mask out of habit and rely strictly on venting/air flow.

It's not like I was directly over the fumes but just the odor made me ill, so I have a clean air flow now. I don't even use CA like I used to but try to incorporate more epoxies in my work... still venting as that smell is awful too. After my health issues the past couple years things have changed, I have changed and I used to enjoy painting and heavy assembly work with plastics and resin.

Out of the blue during a routine examine I had an initial diagnosis of COPD by an x-ray technician/radiologists who really misread the film, but after a battery of tests by a Pulmonologist it was concluded I had an unusual large capacity of lung function (mainly what most swimmers and runners have) and that I had no issues but was just now hypersensitive to odors.

Even the odor of dried/cured resin I can smell now.




Jeff