Acceptable ranges of temperature and humidity for applying lacquer paint?

[oly]

If it matters, I'm applying touch up lacquer paint with a brush, match stick, or tooth pick.

The paint is from PaintScratch.com and when cured (two weeks) is slightly grey so that it does not match the black on my 1985 911. When I applied it, the temperature was about 60 F and the humidity was about 55%. The only information that I get from PaintScratch is that it should not be applied above 120F.

[Ernesto 911]

Hi Art,
The temp and humidity variables during your application of the touch up paint were acceptable.
Was your finish a base coat/clear coat color? If so, color will not match until a clear coat is applied.You can find clear coat in a spray bomb at the auto parts stores if that is the case.
Assuming the formula from PaintScratch was correct, fresh, and mixed well before using, another step to do is prepping with a good wax and grease remover like PPG DX330 to remove anything on the surface that can contaminate your results and cause a paint failure.
Hand application of paint will also look different than the paint applied with professional tools.

Touch up paint can be tough to match an existing finish...original or not.
Believe it or not Black and White are tough to hit.
As many others have said here, you can find a local auto parts or paint & body supply store that will mix small quantities of paint to match your color. Some, like our store, even have equipment to analyze the paint on your car and create a more accurate formula that can account for fading, or the variant of the factory color you have.

Regards,
Ernie

[oly]

Ernie,
Thanks for the post. The bottle marking indicates that the PaintScratch paint was not meant to be clear coated, but I think that this may have been an error. I did test samples of the Paintscratch and some 20 year old Porsche black touch up paint. After an hour of drying at about 70 F, the Paintscratch looks very dull and the Porsche paint looks very shiny.

What is the minimum temperature that I can apply the lacquer and still get good results?

[Buckterrier]

Black paint should not look gray. Black is black is black. I agree 100% that whites can be difficult to match but black is black. Even if clear was meant to be on top it would not make the black blacker. It would give it more depth & protect the basecoat from UV light. Applying lacquer in high humidity will cause blushing which may look slightly gray.

[Ernesto 911]

Art,

I was wondering how you ended up with lacquer as your touch up paint so I visited the PaintScratch.com site
They state that the only sell basecoat colors there (they just say you can thin with lacquer thinner).
If that is the case your basecoat paint will dry dull black and need the clearcoat to give it gloss, and as Mark said its depth and protection.

To answer your question, the minimum temperature that you can apply automotive paint depends on the temperature range of thinner or reducer used with the product. Lacquer uses thinner and basecoat/clearcoat paints use reducer. We don't know if the PaintScratch product has either in it.
A medium range product is for use in temperatures moderate to warm…Let’s say 65-80 degrees.
I would not use thinner in paint calling for reducer.

Your paint defect could have been a color mistake, bad product, cheap thinner/reducer, a reaction to contaminants still on the car, cold paint or indeed as Mark says high humidity. The more uncontrolled variables, the worse it is to diagnose paint defects. I’m glad to hear you tested another sample, hopefully at room temp.

I don’t know if your car has single stage paint or a basecoat/clearcoat finish.

If you asked me to mix you a cheaper basecoat/clearcoat formula, per the code 700/LO41, you would get a single, cheaper mixing color “black” cut with mixing clear and poured in a can.
Coverage is less and the match may or may not be perfect.
However if you asked for a top-shelf formula I would have to ask you which of the two “black” variants in enamel…Or the three “black” variants in urethane you wanted to go with.
Coverage would be better and the color match would better account for the different blacks encountered by body shops painting an ’85 911.

Actually, I would use my Prophet equipment to match your car.

Regards,
Ernie

[oly]

Mark & Ernie,

Thanks for the detailed posts, they are very helpful!

[oly]

Ernie,

I'm using acrylic lacquer thinner from a local body shop. Does that have a single minimum temperature for application? Or does it come in different minimum temperature values?

I believe that the car has its original paint and that the paint is not clear coated because:
1. I did the polish check and that produces black marks on my polish cloth
2. I've read here that Porsche did not start clear coating black until some time after 1990

Thanks for your offer to match and supply paint. My plan though is to use the Porsche Touch-up paint since it flows well, drys to the correct color and gloss, and drys without any bumps. I want to thin this paint because that is the only way that I know of to get the thin coats that I want. And because the packaging for this paint says "lacquer" I think that the acrylic lacquer thinner is the correct thinner.

[Ernesto 911]

Art,

You're welcome!

I'm guessing the lacquer thinner is "general purpose" I'd expect it to be in the 65-80 degree range.
Lacquer paint hasn't been commonly available from manufacturers for some time now even though thinner is still around.
Back in the day lacquer thinners were available for different temp ranges from a good PB&E supply store.
I'm betting your original finish is a single stage acrylic enamel, as most of the color names for an '85 were designated "poly" in the PPG book.

Good luck,
Ernie

[oly]

Okay, thanks again Ernie.