So the previous owners had a dog that they liked to keep in the garage for whatever reason. Dogs being dogs, it didn't like being cooped up in there and clawed at any opening it could to try to get out. This resulted in a fair bit of damage to both the door leading outside (which is a writeoff thanks to both the dog damage and just general rot and neglect) and the door leading into the house.
I had previously repainted in the inside half of the door leading into the house, just so I could contain the ugliness to the less trafficked side of the world, while I mulled over the option of either replacing the door or fixing the other side.
This weekend I finally got around to fixing the other side.
Step 1: forget to take a "before" picture.
Oops. I thought I'd taken a picture of that side of the door before that I could reuse, but apparently I never did.
Step 2: chisel out the damaged section of plywood veneer.
The dog had managed to claw its way through two plys of the plywood, so I scored along the edges of the damage and chiseled away the remains down to a flat base of reasonably solid wood.
Step 3: glue in a conveniently perfectly sized piece of veneer sliced from a 2x4.
So a few weeks ago when I was replacing my broken bandsaw blade and tires I made some test cuts by slicing some 1/16"-ish veneer slabs out of a scrap piece of crappy 2x4. Fast forward to today and it just so happens that one of those pieces is the perfect size and thickness to exactly fill the space left after chiseling away the damaged plywood. Weird how that works out sometimes.
At this point I had also given the door a bit of a sanding. I was hoping to possibly sand smooth the places where the paint had chipped out but the sanding didn't go as smoothly as I'd hoped so I opted to fill the chips and scratches and other damage with wood filler.
Step 4: the wood filler.
I ended up doing two coats of wood filler. Initially I had only filled the big divots, but upon reflection I decided that if I was going to go to all this work I might as well go all in, so I sanded, applied a second coat, then sanded everything down smooth.
Step 5: the paint.
It took three coats of paint to cover the grimy "white" that the door was blessed with previously. I had a lot of difficulty fighting sags in the paint, and ended up having to do a fair bit of sanding after coat 2 to get things reasonably smooth before applying coat 3. I also thinned the paint a little for coat 3 which helped me smooth on just the thinnest possible coat of paint. The end result isn't really perfect, but it's good enough and a huge improvement over what I started out with.
I still need to replace the trim, but that's a project for another day.