Primed trim peeling

I've got a builder grade 80s home and I'm slowly painting and updating it. I'm working on the stairs now. The stringers, railing, newel posts are all stained oak that I want to paint semi-gloss white. I have seen my exact staircase on many blogs and forums, so I know it is a common configuration!
I used TSP first to get the grime off, then a light sanding with 100 grit. I then used Kilz Premium and let it dry 24 hours. I used Benjamin Moore white semi-gloss (the Ben product). Two days later you can take your fingernail and gently scrape right down to the wood. The paint isn't peeling by itself, but my nail can peel it right up.

I have read so many articles and forum posts about priming and painting that I'm about to go blind, and I still don't see why the Kilz didn't work. I hate to use the oil-based Kilz because I don't want to use oil-based paint because of the VOC odors and clean up, and am pretty sure I'd have to if I use the original Kilz or the BIN product.

I've read about using a sander/deglossing product, I've read about Sherwin Williams Preprite Problock Seals and Bonds, and am not sure what I need here, but I DO know that I'm going to have to get all the paint off and start over, not anything I'm looking forward to, given the angles, curves and corners of the newel post and railing.

Any reason for the Kilz not to work after I used TSP and sanded?

 

Assuming the kilz premium is latex - that's the likely culprit. A solvent based primer should be used whenever you paint over poly/varnish or switch from oil base enamel to latex. SWP's problock primer is similar to oil base kilz. Liquid deglossers also have a strong odor. Fresh air ventilation is the best way to dissipate the odor from solvents.

TSP can also also be an issue. When the TSP isn't rinsed well, the remaining residue can cause adhesion problems although sanding probably removed any leftover residue.

While there is no guarantee what you have will hold up long term, 2 days is too soon to know if the paint will stay adhered long term. It can take a week or more for latex coatings to cure.

 

Latex Kilz is known to have adhesion issues.

Additionally, did you rinse off the TSP? It can also create adhesion issues.

Personally, I would sand this mess off, prime with an oil based primer and then the paint you've chosen.

EDIT: Dang, looks like Mark beat me

 

Thanks so much! I had such high hopes for Kilz! I did not rinse the TSP off carefully, just scrubbed the grime off and used a damp cloth to wipe afterwards, but I did sand it. I will take better care with the TSP in the future, as I move on to more projects.

I didn't think I could put latex paint over oil-based primer, so that's why I went with the latex Kilz.

That is also good to know that maybe more curing time is necessary before I begin the chore of starting over.

 

There are many times when the best paint job will involve a solvent based primer with a latex top coat. You can almost always apply any latex paint over top of most any solvent based primer. I rarely use TSP inside because it needs to be rinsed well but do use it a lot outside where I can rinse it with a water hose

Mitch, I had a head start

 

So do I need to use a detergent or will sanding remove anything that lingers?

The hand rail I am about to paint next doesn't have true grime on it, but who knows what wood polishes/dusting sprays might have been used on it before we lived in the house. I could use Simple Green if that would be a good idea prior to sanding. Rinsing TSP on this 15' railing indoors would be messy.

 

Simple Green would be good, you still want to rinse but it won't be critical like it is with TSP. Whether or not to clean first is a judgement call. You don't want to paint over or sand in a bunch of grime or wax but it doesn't need to be pristine either. I usually rely on a liquid deglosser to remove any wax or finger oils but I'm sure there are household cleaners that will work just as well at removing contaminants.