drywall
My half bath rough in is under the staircase. The original builders put an angled side of the ceiling. I tried hanging a piece of drywall but I'm not super happy with the result. The right side sticks out too much.
Would a prefill layer of (hot?) mud run on each edge fix this? Would normal taping fix this? Or should I take it down and start over? If I need to take it down, would hanging a plywood backer first help?
Though you might be able to mud over them, you're looking at 1-2' of mud (feathered) around each screw to make it not noticeable, which basically means you'd be covering the entire piece of drywall with mud. Like pretty much everything in construction, it will be much easier to do it properly now rather than try to fix it later.
If your driver is slipping out, you are probably not using the right bits (or your bit is worn out) or are not pushing hard enough on the drill to prevent the bit from slipping out. Make sure the bit fits well in the screw head: it should not have any room to wiggle in any direction, and should not slide around. #2 Philips is the usual here, but depending on the screw head it may need to be a sharper/longer or blunt tip.
It could also be that your screws are not the right type. If you're going into wood studs, generally you should use coarse thread screws. If you're going into metal studs, it should be fine-threaded screws.
Since the board is also 5/8, it may be that the screws are not long enough. Try longer screws, which should get a better grip on the studs behind so once they start going in, they'll go in as deep as you need.
Assuming you have fixed the water problem (if not, give up), why not simply attach drywall directly to the entire surface. You may be able to adhere it with construction adhesive. If not, use screws, if necessary, with anchors behind them. If it is available, consider moisture resistant drywall or even paperless.
You can then put on any surface finish you want.
Best Answer
Prefill will take care of it. Prefill only enough to effectively get tape up there, then begin buildup. Feel free to go a little heavy, sand, go a little heavy, sand, etc.
Just remember though, hot mud only dries quickly on the surface, just enough to lightly sand and recoat. It's still wet underneath, so don't go too thick per coat, and make sure you give it a couple days dry time before priming and painting.