you don't succeed, gouge a big hole in your wall and try again!
Fixing this corner of the drywall in my craft room was making me guano loco. So finally, I took my Exacto knife and cut out as much of the old compound as I could. I guess the angle of the wall coupled with the new addition settling prohibited a smooth job the first time, so I figured starting over with drywall mesh and compound was the way to go. It's curing right now. My goal is to add the skim coat and repaint the corner by this weekend. It already looks (and feels) much better.
While I was working painting and staining projects this weekend, I realized I had never shown you a picture of my paint storage. It's a mesh cart I got from Target about a year ago (didn't see it on their website, though). The bottom drawer holds little cans of stain and touch up cans of all our wall colors. The second drawer is primers, spackle compounds, and the trim paints. The top drawer is painting supplies like rollers, steel wool, sponges, trimmers and stirrers. The basket on the top holds spray paints, polyurethane, the paintbrush cleaning jar, metal brush for cleaning bristles, and my much-loved angled paintbrush. The beauty of this cart is that it wheels easily in and out of the kitchen closet which means I don't have to dig for what I want. One of the best $20.00 I've ever spent.

