Paint 101

gerlacr · Mar 25, 2003

I am nearing completion of my CADPlan loader and starting to think about paint. I’m not too worried about color yet. I just need to look into the basics. How do I prep the raw metal? What kind of primer do I use? I have an air compressor and a small suction type spray gun. Should I get a gravity feed type gun? Can I use aerosol cans for the primer and then the air sprayer for the finish coat? What kind of paint do I use? Acrylic, alkyd? Are some types of paint tougher and last longer in the sun but cost more? Does the finish have to be baked? Help!!!! /forums/images/graemlins/confused.gif

shado · Mar 26, 2003

That depends on how durable you want. I did some automotive painting a while back and my studies concluded the best way to do a good job when starting with bare metal was metal prep, primer, sealer, then topcoat. But I doubt you would want to go to that much trouble, especially if the item in question will be taking a beating from time to time. I would at least make sure the metal is clean down to it's bare surface, you can buy a metal prep 'spray' now to etch the metal, then shoot a decent primer (grey, such as 100 or 110S type), then the top coat or 'color' coat, which enamel based with a hardner added would probably suffice. For durability & high-heat applications, I used some stuff called 'Durathane' by Ditzler (if my memory is working right) some time ago, cost was somewhat reasonable back then but I don't know what it runs these days. While the item is in primer, it can't be exposed to any moisture, primer is not a vapor barrier, a big mistake is driving a car around in primer, then shooting the topcoat shortly afterward. Rust may take a while, but it would eventually appear. As far as what type of gun, looks like a lot of people have adopted over to the gravity-feed versions. I don't know how well they work when needing to shoot upward, I still have the suction type and a pressure-pot available.
J.W.

mbrule · Mar 26, 2003

I do quite a bit of painting, my experience is:
1. Use whatever gun you are most comfortable with
2. Use quality materials
3. Follow the directions when mixing

When I am in a situation like you and am not sure what use, I go to my local paint supplier, and explain what I am doing and look for his advice.

I used self-etching primer and Duponts Centari enamal on my Cadplans loader and it is standing up quite well.

Hope this helps!

Matt

RayDiers · Mar 28, 2003

Have a look at this painting system.

POR15

They say it seals out moisture and does not allow rust to happen and is very tough.

Ray

gerlacr · Mar 31, 2003

Ray

Thanks for the link. I will look into it. Is this used as primer or for a final coat? The web page mentions that it is UV sensitive and needs a top coat.

Ron