Ask the paint chemist

Elwarpo · 2025-09-10T11:12:50-0400

First off, I hope this is in the right subforum, if not, mods can you please move it.

I have learned a lot here and thought I would give back.

I am a paint chemist and have been inventing paint for the last almost 40 years. I regularly travel the world and give coatings training. So I know people have questions on paint and would like to help, so please post up any questions you have on paint. I will not recommend any company or brands but help you understand what type of paint will work best and help with questions on surface preparation and how to use paint.

My first and most important piece of advice, RTFI (Read The Friggin Instructions) on the paint. 99% of paint issues are on the wrong end of the paint brush, meaning not the paint... And no, you will not lose you man card by reading them

DoomMeister · 2025-09-10T12:52:42-0400

I’ll have to check with you the next time I run into a paint issue (and did read the instructions first). Being a former military technical instructor I am very familiar with RTFM.

Dogpilot · 2025-09-10T13:40:11-0400

Paint. I have had far too many dealings with paint. I worked my way through college partially as a painter, as my Navy scholarship didn't even meet the cost of both eating and housing. In a weird twist of fate, I ended up managing a huge painting facility at our aircraft re-work facility. So big, we were fined $22,000 a month for our emissions and it was owned by the government. Later in life, I owned an aircraft painting facility as part of my repair station for aircraft.

There is so much to know about paint, prep, and disposal of materials. It is ever changing as it evolves. Prep is perhaps one of the many things that affect how your paint comes out. Infinitesimal bits of silicone will cause huge defects in the coating. Interactions with primers, temperatures, humidity, how it is laid on. It goes on forever. All I know is had so much education on it, and it all is to naught, since the tech moves on so fast.

On a funny note. When we first got the F-18 for its first overhaul cycles we had a huge problem. Nobody had worked out how we were suppose to get the old paint off to put on a new shiny coat on. All of the traditional chemical methods also had the side effect of dissolving the composite panels (we used prototype #3 for testing, it was never going to fly again). We looked into all kinds of methods, including sandblasting with dry ice. Finally ended up settling on plastic media blasting. It worked, but left material behind. You cannot sand the aircraft or you compromise the skin. So the first coating of very special epoxy primer was sanded, by hand. It was a major PIA. I did like test flying the F-18, probably the easiest plane I ever flew. Even auto trimmed for you. Not quite sure what I was supposed to do, felt at times like I was just the safety monkey. My biggest problem was setting the frequency on the radio with the stupid HOTAS joystick on the throttle. I flew a bunch of planes at the same time and all the others had much more evolved tech: knobs.