First paint job: quick question about acrylic enamel v. urethane

[JoshPDX]

Well after a full day of pulling my hair out trying to locate and purchase a simple and economical paint system, I was happy to find this site!

I have a '56 Studebaker Hawk that I am repainting in my garage-- I took it down to bare metal and have a couple coats of Martin Senour red acrylic primer on it (it doesn't say whether it's enamel, urethane, laquer...).

So I am looking at some of the paint kits online from Kirker that are acrylic enamel or urethane-- for about 100 bucks you get everything you need.

I'm not sure what is compatible with my primer (or maybe it doesn't matter as long as it's not laquer?), nor do I know what's better for a newbie on a budget... the enamel and urethane are about the same price, but I've heard urethane is easier for beginners.

[JCCLARK]

Night and day difference between enamel and urethane.
Enamel is probably the least durable paint out there,
very old technology.
Urethane is one of the toughest paints out there.
The clear that most use to cover basecoat is urethane.
The only thing tougher is polyurethane, which you don't see much.
Imron is a popular poly, it's used on aircraft.
Some clears are polyurethanes.
They're the best, but urethanes are very close.:cool:

[stealth1]

You say the Acrylic primer doesn't say what it is ? Did you add hardener/catalyst to the primer ? If not it is just 1k Lacquer primer, which as you will learn is not the best foundation for a solid long lasting paint job, but it will work. The best way to go is 2k epoxy primer, then 2k urethane primer, then your Urethane based top coat over that, be it basecoat/clearcoat or single stage Urethane paint.

If you already have the primer done and are ready for paint, then you could apply Acrylic enamel, Urethane enamel, or urethane basecoat/clearcoat and still be OK, it's just that the 1K lacquer primer will be your weakest link, but with a good Urethane paint system it should still last for many years. If you are using a metallic color I would recommend basecoat/clearcoat system for easier application and you can sand it smooth and buff it where single stage metallic you have to be careful not to cut into the metallics when wet sanding and buffing after the paint has been applied.

I fully agree with JCCLARK that I would highly recommend using Urethane as it is night and day difference as far as how hard the paint gets and how long it will last before it begins to fade etc, plus it is easier to take care of. Acrylic enamel will begin to fade within a few years in the sun if not waxed regularly, and it remains softer than Urethane based paints and is much harder to buff without burning the paint. So all in all stay away from Acrylic enamel based paints unless it is a work truck or a piece of farm machinery.

I would consider Dupont Nason single stage urethane as it is priced right, and even the Kirker line you are looking at but in Urethane. Nason can be bought from local Dupont dealers and Oreilly's auto parts stores can also get it for you if you have one of those local to you................best of luck

[JoshPDX]

Thanks a million to both of you. I do believe you may have saved my paintjob and sanity. I now see in hindsight where I let impatience get the best of me in this process-- the next paintjob will go twice as fast, and cost half as much!

I will definately go with the urethane, and hopefully pick it up tomorrow at DuPont (Viper red).

One last question- if I decide later I want to clearcoat it, do I have that option or is there a limited window of opportunity (I'm just looking at my budget here).

Thanks again. Can't wait to let you guys know how it turns out!

[Len]

Thanks a million to both of you. I do believe you may have saved my paintjob and sanity. I now see in hindsight where I let impatience get the best of me in this process-- the next paintjob will go twice as fast, and cost half as much!

I will definately go with the urethane, and hopefully pick it up tomorrow at DuPont (Viper red).

One last question- if I decide later I want to clearcoat it, do I have that option or is there a limited window of opportunity (I'm just looking at my budget here).

Thanks again. Can't wait to let you guys know how it turns out!

While urethane is a great product it can also be much more harmful to your health. Be sure to protect yourself PROPERLY when you spray anything but especially urethane products.

[stealth1]

Yes you could sand the single stage urethane with say 800 grit in the future and apply clear over it, but there is no better time than the present to do so because it will already be masked off and clean. If you want a clearcoat then just check the price of basecoat/clearcoat urethane versus single stage urethane in the Dupont Nason and see if the price difference is that much for your color. Sometimes the price difference is not that much, but red is always an expensive color regardless of the paint system you are using..........................best of luck with your project

[JoshPDX]

Thanks a million-- I'll let you guys know how it comes out!

[lucky2505]

I'm confused (Happens alot). Are you saying it is best to use a 2k urethane primer between 2k epoxy primer and urethane topcoat?

You say the Acrylic primer doesn't say what it is ? Did you add hardener/catalyst to the primer ? If not it is just 1k Lacquer primer, which as you will learn is not the best foundation for a solid long lasting paint job, but it will work. The best way to go is 2k epoxy primer, then 2k urethane primer, then your Urethane based top coat over that, be it basecoat/clearcoat or single stage Urethane paint.

[another2centsworth]

not necessarily....If you have a good 2K topcoat that is sound...be it enamel or urethane you need no epoxy.

[lucky2505]

Thanks for all your advice. Is it safe to spray urethane with a quality mask and new canisters or is the hooded system you use on Spray Paint 101 necessary?

While urethane is a great product it can also be much more harmful to your health. Be sure to protect yourself PROPERLY when you spray anything but especially urethane products.

[Len]

Thanks for all your advice. Is it safe to spray urethane with a quality mask and new canisters or is the hooded system you use on Spray Paint 101 necessary?

A canister mask works BUT it's not nearly as safe as a supplied air system. The main reason for this is that the cartridge mask works on negative pressure and tends to leak around the edges as you spray and the overspray coats the prefilters and the chance of leaking increases. When spraying non-hardened materials this leaking is less dangerous but when using hardened products like urethane it's highly advisable to use a supplied air system. If you vent the room well and you're only planning on painting one car then you can make an argument for the cartridge mask but because of the toxicity of the paint and the availability of a good supplied air system for under $500 it's highly advisable to play it safe.

If the supplied air system air system leaks it will leak OUT not in and you wouldn't even smell the paint and, as long as you place your pump in clean air, you can relax and enjoy spraying any kind of paint.