Paint question

[Jasonrkba]

Im restoring my 1-70 mac. The air filter cover, I stripped it all the way down and put two coats of black enamel paint on it. It looked great. As an added bonus three days later I put a light coat of clear on it. The clear wrinkled up like a bad sunburn. Any one have an idea why? Before I applied the black I wiped it down real good with acetone.

 

[cookies]

The black base coat is incompatible with the clear (dissolved and softened it), the clear caused lifting in the base coat and when it dried and shrunk it pulled the black paint creating wrinkles.

 

[Jasonrkba]

Looks like I'll be sanding it back down to bare metal and starting over. Disappointing because it really looked good.

 

[cookies]

when you repaint let it flash off all the solvents then bake it in a oven or box using a space heater or hair dryer at around 140-150 for 2-3 hrs and it should be hard as nails when it cools saving you a week

 

[buzz sawyer]

I apply two coats of clear poly while the last color coat is still tacky. Never had a problem with wrinkling. Make sure you're not mixing enamel and lacquer.
Some paints caution about recoating time - some recommend several days. Baking is a good idea.

 

[Jasonrkba]

Sounds good. I gave it the recommended 48hrs but that obviously wasn't enough.

 

[Huskybill]

I don’t like using clear coat. My pc husky paint says 24 hrs between coats of orange. I do very thin coats but multiple coats.

What paint is good enough? On my equipment I use Rustoleum it lasts for decades.

 

[Jasonrkba]

Both products where rustoleum. 48hr wait time as suggested on the back of the can.

 

[Huskybill]

The 48 hours matters how thick you layer the coats too.

 

[cookies]

enamel paints have a 2 stage curing process. the first stage is evaporation of volatiles, this is the reason for not applying in thick coats and waiting between coats. the second stage is a chemical polymerization reaction, this is the part where the paint physically hardens. depending on paint blend, applied thickness and temperature it can take several days or even months to fully harden. this is why i suggested the baking. Baking will force cure the polymers, reduce viscosity and increase flow to give a smoother finish that should be fully hardened in about 24hrs.
Many years ago I painted a lawnmower deck using enamel spray paint in november, it took until march to finish hardening due to colder temperatures and laying it on in several thick coats. I made it a point to learn from that mistake!

 

[sled_22]

Here's a lesson that applies to the curing process my wife doesn't understand.
She wanted to paint some shepherd hooks that had become rusted. So I help her sand them down, wipe clean, then she get the cardboard out and paints them out in the sun... I said you should move them to the shade, they'll dry faster. She didn't believe me. When she went to pick them up a few hours later, paint still tacky wet and covered her hand.
So the next day I sanded that down and repainted them in the shade of the garage. It was dry in about 20 minutes roughly the same ambient temp/conditions.

TL;DR
The sun's radiation effects paint's curing process.

 

[a. palmer jr.]

Are you using spray cans to paint the saw or a spray gun? Sometimes spray enamel in the spray cans isn't very good quality and will wrinkle when even clear enamel is sprayed on it. I usually try to buy paint from an automotive paint store but will caution you it's getting expensive..I painted the tailgate on my S-10 and bought a pint of metallic red and it was around $50 and didn't include the hardener or the clear..

 

[Jasonrkba]

Rattle cans. Red is the most expensive. Im just going to bake it with no clear.

 

[a. palmer jr.]

Rattle cans. Red is the most expensive. Im just going to bake it with no clear.

When I painted my tail gate I had them put the clear in the paint so all I mixed in was the hardener. Thought about clearcoating it later but it looks okay as it is...Hardened acrylic enamel.

 

[Jasonrkba]

Oddly enough 25-30 years ago I went to school for auto body repair. While I went on to do other things to pay the bills many of the lessons learned still apply today. The thing is like every thing else science and technology change at a crazy pace. I never was a very good painter but I did excel at body work. I think had I used a good primer there would not have been an issue. Cookies nailed in his first post. I'm just glad I had not applied the decal yet.

 

[a. palmer jr.]

Since I first started messing with cars back in the early sixties paint has improved greatly, it's a little easier to paint and do a decent job nowadays but the paint today requires that you protect yourself, a good mask is a must have..