Two tone job with leftover single stage urethane

[magnang]

So... I screwed up a paint job on my gas tank by using Duplicolor High Build Enamel. This paint stays quite soft and did not hold up well to fine line tape when came the time to mask some pinstripes.

Money is getting tight for me on this project. However the good news is that I have some leftover single stage urethane from previous truck I had worked on and the color will work on this bike. I also have lots of 2K urethane clear on hand.

I was wondering if I should be ok to use these as follows:

- Wetsand the duplicolor down untill all the marks are gone.
- Basecoat over it with the SS urethane and let it cure
- Do the stripes with enamel (probably duplicolor as I have some left)
- Clear the whole thing with 2K

 

[Scratcher09]

I would not put a rattle can enamel between a urethane base and clear. It may react negatively. Also, if you use 2k clear over the enamel I think the enamel would never fully cure. (Enamel needs air to cure). Sealer should be used before spraying the base just to minimize any chance of the existing enamel reacting funny with the urethane. But then again, it will never fully cure, so best thing would be to strip it and start from scratch. If you do it right, you won't have to worry about another redo.

 

[magnang]

Thanks for the insight, I will start over again and re-prime over bare metal

As far as pinstripes, would I be better off using some lacquer once my single stage coat is on? It cures much faster than enamel. The single stage should be pretty resistant to lacquer thinner once cured right ? Provided I scuff up the areas where the stripes will be with say 800 grit?

I would rather not have to buy another can of urethane for a couple of pinstripes...

 

[Scratcher09]

Using urethane clear over a lacquer is not a good idea because it will likely delaminate--could be next week, could be five years from now. Some people do it. I would not chance it.

Here's another option if you are trying to avoid buying another can of urethane base coat and catalyst. You could use One Shot enamel. The 4 oz cans are pretty cheap. When clearing over them, I add just a tiny bit of the same hardener to be used in the clear. Make sure the enamel is cured before clearing and when clearing, be sure to shoot a tack coat (light mist coat) for the first coat. This will lessen the chance of a reaction with the clear. Using One Shot is not ideal but it has been around a long time and is widely used. I've seen it used in graphics that are cleared and I have used it like that myself.

Another option is to find a supply shop that sells small cans of base coat. Some do. You can also look for places that sell small cans online like coastairbrush.com. Most of the paints they sell are available in two ounce cans.

Auto Air waterborne paints are another option. Four ounce bottles are inexpensive. And water base paints have come a long way in the last two decades. Most automotive manufactures are now using water base paints. And the industry is going to have to switch over to water base systems in the near future due to government regulation. They are great for graphics. No time window to worry about. Only difference is you have to build up light coats instead of spraying wet coats and no sanding is needed before clearing. And they are compatible with urethane clearcoats.

Im just trying to give you some options that are known to work.

 

[High On Octane]

Lacquer and urethane does NOT work together! As Scratcher09 stated, you're best to strip the tank and start over. My question to you is why do you want to use clear coat over a single stage paint anyways? And as far as pin striping, the One Shot paint does not require you to sand anything for it to adhere. But again, make sure your first coat of clear is a tack/bridge coat. The One Shot tends to react to medium/wet coats. Really, the proper way to do any kind of multi-tone paint jobs is to clear coat in between each layer. This keeps the original layer unaffected by any mistakes.

The single stage should be pretty resistant to lacquer thinner once cured right ? Provided I scuff up the areas where the stripes will be with say 800 grit?

If it is a very small amount of lacquer thinner on a rag, you may be ok for small clean up. Typically, lacquer thinner will not necessarily eat the paint, but it does tend to take the gloss out of it and leave it prone to staining. Depending on what you are doing, a quality wax & grease remover usually is safer and works almost as well for clean up.




Scottie J