Ready for being stripped down to the bare wood.
I actually really like an original cabinet with reasonable patina. But this is just hacked up and gross. Time to fix it.
Every time I do a cabinet I find some weird flaw, here a whole chunk of ply was just detached.
On all corners of the head and cabinet I countersink Kreg screws, they grab really well. I then trickle fiberglass resin into each one. I finish with body filler but I only want a skim coat of filler at the end. This cabinet and head had solid corner joints I did not have to fix them, just reinforce them.
I don't know what happened here, it looks like a beaver gnawed at the corner. Made a dam from a gloss faced piece of cardboard (Cheerios I think), then pour the resin in. A couple of raised screw heads are embedded in there to provide a strong grip. Being the front you obviously want this to look good. This is the third cabinet I have done and the wood quality is always crap. I spent quite a bit effort removing the waviness, it turned out well but not perfect.
It looks like a random collection of materials. The lightest colour streaks are actually factory filler. It seems an awful lot like plaster. If it was at all loose I chewed it out and replaced it.
Honestly this is where the most time is spent. Many touch ups of filler. Glazing putty only for the smallest of flaws and never to repair a corner, only to smooth it. Even the tiniest wrinkle at a corner was fixed with resin, then filler if there were any voids.
I know this is a common issue but as the first time I had to deal with it. I cut new edges and glued them in down both sides.