Glossy Trim

jimbo123

My name is Jim. I'm a licensed painter in Florida who has a lot to learn about the trade. My dad was a painter for many years. I used to help him as a youngster. However I didn't pay attention too much to his teachings. He would slap a paintbrush in my hand and I would paint. I didn't ask too many questions. Now that he's gone and I'm doing it for myself, I have a ton of technical questions. The business side doesn't scare me as much due to my background, but the technical side terrifies me. I should probably go paint for someone else for a year or two to learn the trade better, but I've got to make a living to. I have discovered this website and have a ton of questions and hope that you will be patient with me. For today I have two questions. Both embarassingly simple. I KNOW THE TEXTBOOK ANSWERS. WHAT I NEED TO KNOW IS WHAT YOU GUYS DO IN THE FIELD ON A DAILY BASIS.

1. You walk into a house to give an interior bid. How do you determine if the previous trim was done in oil or latex? I tried acetone on it as suggested at Sherwin Williams and the paint didn't react. (I was told that latex will get "gummy") Therefore, I am assuming it is oil. Will old (10 years old) latex get gummy also?

2. The trim is in good shape. It is glossy however. My question is will you always, without a doubt, no questions asked, always-always-always sand or degloss a glossy coat? Will I get in trouble if I just paint over the glossy trim. The trim is in good shape and as I stated I am pretty sure it is oil. I'm using Sherwin Williams Enamel, Gloss. If it's 100% sure I'm going to screw up by doing this, then I don't want to do it. But also, If I can be comfortably sure that the paint will hold, then I would like to just paint over the old trim after cleaning. What do you do?

Thanks in advance for your help.

Jim

jimbo123

I will be using oil to go over oil.

rws

Oil needs to be deglossed using 220 production paper.Another way to test is to use wilbond (a liquid deglosser) on a rag. Rub the trim if you get drag it is latex.

AAPaint

Any gloss paint needs de-glossed before repainting. You can sand or use a chemical deglosser. Sanding is the simplest. Sand, tack, paint. Walls are the same. Satin sheen or higher, we pole sand.

Testing for oil or latex is easy. Keep a jug of denatured alcohol on your truck. Put some on a rag, if you pick up color, it's latex. RWS basically said this already, just left out what solvent.

__________________
-AAPaint

AA Quality Painting & Pressure Washing LLC
Jacksonville Painters
Jacksonville, FL.

Brushslingers

What they said, however.. after 25 years of this I can look at it and tell you 99% of the time if it's latex or oil.

Certainly "scuff" sand before painting, as far as a real test to see if it's oil or not, denatured alcohol works well.. as AA said, if you get color on the rag....

__________________
Benn

Danahy

Ditto this.

I used to use nail polish remover with Acetone to check. Nowadays, I just know either by feel or a crack test. Latex bends, Oil snaps.