I'm not an expert but have painted my kitchen cabinets twice. I think you might be taking the sanding part too seriously. I washed the cabinets with TSP, hand-sanded with large grit sandpaper (I don't remember the number), primed, lightly sanded by hand with a very fine grit sandpaper, wiped down to get the dust off, painted a coat, lightly hand sand, wipe, and the last coat.

The paint never peeled or fell off. It adhered just fine. The first time I painted was over stained walnut and the second time was over the paint of these same cabinets.

I'm in the process/purgatory of this project right now.

blfenton is right - you don't need to sand down to the wood. Just scuff sanding with 120 grit paper to give the old finish tooth for the new finish to stick to. Due to some issues along the way (I foolishly stacked up some completed doors and they ended up sticking) I did sand some parts to completely remove some finished paint. When I did this I got down to bare wood in some places. Unfortunately, when I primed and painted again the sheen appears somewhat different where I got down to bare wood. Anyway, I'm just suggesting that it could be more headache/heartache than it's worth to sand so much. If you happen to find old streaks or runs I would make the effort to get those sanded out now.

A few other words of advice that I've picked up from reading or wish someone had told me before I started -

Don't use TSP to clean as it leaves a residue that can interfere with adhesion if not cleaned off properly.

Vacuum off all dust and use a tack cloth. For dust in corners use a paintbrush to get small particles of dust out.

Sometimes it's good to do two coats of primer. I wish I'd done this on my entire project - especially when I had some bare wood showing.

Add flowtrol or penetrol to extend the open time and help enhance the leveling.

Wipe up any paint that gets into areas that you're not currently working on - say you're working on the inset area and some paint gets onto a stile - wipe it off so that you're not painting into drying paint.

Maintain a wet edge - I never really understood this one until I got started. I find rather than trying to stretch the brush strokes from one end to another it's better to lay down the paint in a couple of passes and then tip off and do one long brush stroke. Sometimes it's also easier to lay down paint with a roller and then tip off with a brush.

Be careful not to thin too much or apply too much paint because you can experience runs or sags.

When mistakes happen wipe up particles, remove hairs, etc. right away. If you wait too long it's my preference to actually wash off drying paint completely from the piece rather than trying to sand it out later (this is my personal preference).

I also prefer to tape off and remove tape while paint is still very wet and then tape off again when I recoat. This has allowed me to catch bleed through on my hardwood floors. When I didn't do this for my drawer faces/boxes despite cutting the tape the tape did pull in some areas.

If you're installing new hardware consider drilling holes before you paint to avoid damaging your finish coat. Also consider taping over where hinges go especially if they are inset hinges (probably not the correct term), I didn't do this and I'm dreading possibly scraping/sanding out such a small area.

A dumb mistake I've made is not to move the paint closer to where I'm currently working and I've dripped on finished work - try not to move a wet brush over finished work.

Don't paint out of the gallon but pour what you think you'll use into a smaller container. Your brush picks up dust as you go so it's best not to contaminate the whole gallon. Also, don't pour any remaining paint back into the container unless you strain it. Don't forget to stir well and close up the gallon asap.

Another mistake I made was not to caulk the doors before I painted and paint has some microcracks where the inset panel is. Honestly I'm not great at caulking and I'm not positive how exactly you execute this properly but if you're doors are an inset style I'd look into it.

Sorry if I dumped all of this here and you already know all of it. I've found this to be a really long and painstaking process so I'd write a book if I thought I could save anyone from some of my mistakes!

Best of luck to you!!

browneyes, that was all VERY helpful. Thanks. But I am not sure what you mean by "tipping off". I am getting ready to paint trim and walls so I am eagerly searching for all advice!

Tipping off - I think that's what it's called - is when you make one final brush stroke that goes end to end and smooths out the smaller brush strokes.

Good luck, raee! I'm no guru but I have been working on this project for a while now - if you have other questions I'll be checking back (or better yet, someone with more experience will likely answer you!)