3/8 sounds pretty significant to me, too. Setting coupound is fine. The best advice I can give though, is take your time, whether in filling a wide gap, or final finishing. When you're doing a house you intend to live in for years, adding 2-3 days work time "is nothing". I've been very fussy, albeit very slow, with the taping and mudding that I've done in our house. It makes a heck of a difference, not only in the immediate finished product, but in how the seams look as time goes by. With my lack of speed, I wouldn't call myself good at drywall finishing, but when I look around my house, I'm much more satisfied with my own work than I am with that of the hurry-and-get-on-to-the-next-job professionals. Best of luck with your project!

Hi, I've patched just a few plaster walls. My goal was to cover the hole and make it look good. 3x7 is a small patch. This is how I would do it. Cut a piece of sheetrock 5x9 (thickness isn't important). Score the back of the 9x5 piece 1 inch all around then break the 1 inch piece off the back then peel the 1 inch piece off the front paper. You should now have a piece that is 3x7 on the back and 9x5 on the front. Fit the patch to the hole . It may take some scraping you don't want it too tight. Spread some mud on the edge of the hole and patch and the paper on the patch. Set it in the hole a use a 4 inch blade to set the patch. Let it dry. Most times the patch will be a little lower than the original surface let the patch dry finish as needed. Good Luck Woodbutcher

I am not-repeat not-a professional or expert, just a homeowner like yourself. Jost some ideas.... The edges: If it were mine, I think I would just tape and mud the wall and ceiling as best I could, and then cover the wall-ceiling joint crack with a crown molding or maybe even just some quarter-round stock. Light fixtures: On This Old House, when they have to make this cut in drywall, they use a special power tool with a spiral cutting bit that look like a drill bit, that guides on the inside edge of the metal fixture mounting box in the wall or ceiiling. Looks like you did this by hand with a keyhole saw or something similar. From what little I know about it, I'm not sure you can fix this with tape and mud. Again, if it were mine, I think what I would do is go down to Lowe's and buy an inexpensive plastic ceiling medallion, just big enough to cover the ragged part, and install that above the light fixture. It may be a bit "grand" for what looks like a pretty small room, but it's a lot less trouble than tearing out the ceiling and trying again.

I to have tried my hand at tapeing and texturing a few times over the years,what a mess!. Here's how I handled the last few projects,including a couple of room additions, a house that had fire damage and a few patches like yours. Around here builders don't keep sheet rockers on payroll so 1 and two man subs picking up day labor help, operating out of 1 truck pulling a trailer is common. I drive through new additions looking for a drywaller at one of the new houses and ask him to come by to bid my job. I have hired them for various stages from hanging to tape and texture and always been well pleased. If you are bent on diy all the way,buy a case of Bud Lite and give ne a call to come show you how. After it's screwed up beound hope we can go look for a pro to straighten it out.