MTFCA Forum

I am painting some parts with a gloss paint (Rustoleum Appliance Epoxy). The directions say that a second coat cannot be applied unless the gloss is dulled with sandpaper. The parts are very irregular and cannot be sanded. Is there any chemical or solvent that can be applied to the gloss finish that will chemically dull the finish without using sandpaper that will enable me to apply a second coat? Thank you.

I often use a purple scotch pad on irregular parts with good success to dull a shinny surface. I have painted for a lot of years and it’s very important to ruff up all shinny surfaces to promote good adhesion. Hope the helps.

Second that on the Scotch-Brite pads. Best thing for paint prep, especially with your irregular parts since the pads will conform to any shape.
As Mark stated, the maroon VFN (about 300 grit) would probably be best with the harder epoxy appliance paint.
If you weren't shooting epoxy, or other catalyzed paint, the Gray ULF ( about 600 grit) works well to prep between coats.

Most epoxy paints are not UV friendly. That means they will chalk after exposure to sun light.

I have painted for 60 years. No reason to sand between coats, reapply the second coat before the first one completely dries. It will bond with no trouble. As long as you do not have dust problems everything will be fine and a whole lot less trouble.

Painting is a bit of a science / chemistry experiment so the manufacturers give us recommended instructions.
Choosing to follow them or not is your choice, and I have been bit by ignoring them before.
Rustoleum has a TDS for this product on the web here:
https://www.rustoleum.com/-/media/74656 ... 0C54C3.pdf
And the Safety Data Sheet which is a boring read but says it is an old school enamel product like Henry used
https://www.rustoleum.com/MSDS/ENGLISH/ ... YwMDAyOTEy

Ok, the original question was about sanding between recoat layers.
Quote - "The directions say that a second coat cannot be applied unless the gloss is dulled with sandpaper."

On older well cured paint surfaces (or bare metal) it needs something to bite into or it will peel off making a mess.
This is where you need to scuff the finish or use an etching primer to bite in.
But on "fresh" paint it is soft enough to "melt" into layers below bonding it together IF! you follow the recoat time rules.
Rustoleum recommends 2 windows of recoat times

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DRY and RECOAT TIMES
Based on 70ºF (21ºC) and 50% relative humidity. Allow more
time at cooler temperatures. Dries to the touch in 2-4 hours,
to handle in 5-9 hours and is fully dry in 24 hours. Appliance
Epoxy may be recoated within 1 hour or after 24 hours.
-----------------------------------------------

I use a lot of Rustoleum paints and will tell you if you follow that it works fine but....
If you are curing your paint in less than desired conditions, leave more than 24 hours.
If it has not cured enough you will make yourself a very impressive wrinkle finish paint job.
If you create a wrinkle finish job it is a serious PITA to fix leading to lots of bad thoughts, work and time.

Mike

I use Rustoleum Automobile Paint for touch-up on my T and it works great. I do scuff the old paint up a bit. It's available in enamel or lacquer and there is even a product optimized for touch-up.

I have used appliance epoxy enamel for several years. You can apply a second coat as long as you do it within an hour. I have not had very much luck with applying a second coat even after a day or two of drying. I even tried spraying it with a clear enamel several days later, with no luck. It just blisters up. Properly dryed the paint is very tough.