I need to do some touch up painting on trim on several doors inside, they have oil based paint on them now. Can I just apply some kilz to the oil base layer and touch up the areas with regular oil base paint or do I need to try to sand the areas down where I will be touching up and then apply the kilz and the fresh coat?

I have used Bullseye 1-2-3 without sanding the base layer prior to painting trim. It seems to stick to anything. It is not fun to paint on with a brush, however. Kind of like painting with glue.

If completely repainting, sand down any old runs or issues, apply a zinger's primer and topcoat with latex. If your just touching up, grab a quart of color match oil base and touch up....

It's touch up only, not completely repainting.....thanks.....

Thanks...it's just touch up, so I am not sure I want to go that route....

You can touch up oil with oil but it probably won’t look great. I’m assuming it’s semi gloss on trim? How old is the existing and has it yellowed any?

My .02 , paint the trim with good latex and be done . Oil looks great for a few years but fades and yellows. The new paint most likely won't match. Oil based paints in a house is a thing of the past.

We tried the primer/sanding route, still didn’t stick. Either get oil paint to touch it up or replace the trim.
Several paint stores told me they’re getting away from oil paint.

You talking about priming on top of the oil; then latex? Latex will not stick to oil. I had a dumb painter try that without telling me. Made a mess

My house trim was painted 32 years ago with oil . Most of it has been painted over by a pro painter with latex enamel . It was scuffed up .It is sticking fine. It's S&W Pro Classic, enamel finish, interior acrylic latex.

I checked with the painter , she said she did prime with a S&W primer. Anyway , you can make latex enamel stick to oil.

You can if you use a hot enough primer. Sand a little on the existing oil, prime with a good hot primer, and then paint with latex.

Or you can just repaint with oil. That’s why I asked how long the existing paint has been there. If it has yellowed it won’t touch up. Still easier to just repaint with oil if you ask me. Oil is becoming a thing of the past though. Especially in the residential market. Latex paints are just as good now

Existing is about 3 yrs old, it hasn't yellowed at all.....

I little scuffing up and using latex sounds pretty good.....

Yep, if you tell S&W what you want to do they can hook you up. Painters paint latex enamel successfully over oil every day. However, there's nothing slicker than a oil based paint job by someone that knows what they're doing. Top quality brush, sand between coats , thin the paint a little and put on several coats. It'll look like it's been clear coated. But it will fade and yellow over time.

If it's still "fresh" and not yellowed , just touch it up with oil. If you go latex you'll have to sand and prime, then go with a good latex enamel. Talk to the folks at the paint store .

If you want to touch it up, use oil. If you want to prime and repaint the entire frame, sand, prime, and paint with latex.

I would touch it up with oil, but I hate painting and avoid it at all costs.

Is it chips in the finish you are needing to touch up or just normal wear on the parts that get touched? Also what is the door finished with? Or is it just a cased opening?

It's just normal wear on the parts that get touched and a few chips, nothing major and they are cased openings....

S&W Emerald Urethane Trim Enamel interior/exterior is supposed to paint over oil with only a good sanding and cleaning. My painter lady uses it on painted cabinets but hasn't tried it on oil trim. I'd say it ain't cheap either.

Urethane over oil can be tricky. It is a hard paint and if there is no profile for it to grab it will let go. If you use the urethane, make sure you sand the existing oil very good and get a surface profile there for the urethane to bond too. Wipe it down with mineral spirits after sanding before the first coat. Me personally I would stay away from it but it definitely would stand up to wear and tear better than latex. If you are going to go through the trouble of urethane you might as well go back with oil. Just my opinion though.

2Dogs ain’t wrong though. It can be done and you will have a good product in the end if applied right.

Thanks fellas, I appreciate the feedback......