So I got my first sheet of drywall up today. Only took me an hour or two. :P At any rate, I precut the holes for my recessed lights. I cut them a bit larger for some play, but that didn't work as well as planned. The light has line up against one side of the hole leaving quit a large gap on the other side. The trim will not cover. Can I repair this with joint compound and some tape?

 

Yes, but how wide is the gap? It might be better to cut a piece of drywall about an inch or so bigger than the hole, then on the backside of the patch piece cut away everything but the paper except the part that will fit in the hole. You then mud the 3 sides and insert the patch piece like you would tape - makes for a stronger repair.

 

It's probably about 1/2" at the widest. It's shaped like a crescent moon. The can light backs up 90% of the gap.

The light trim just barely touches the edge of the hole. The biggest problem is fuzzy paper sticking out.

 

I'd prefill the hole - doesn't need to be completely filled, just some extra mud to give it strength. Once that's dry shave or sand off any mud that might protrude below the face of the drywall and mud and tape like you normally would.

If it helps, you can cut the radius on the can side of the tape or even make your own using some heavy paper. The art paper the kids use will work although dark colors might bleed thru without a good primer.

 

Ok. So I am hoping I will be done installing drywall tomorrow. I picked up ultralight compound. I really don't know the difference between them all except for the weight of it. Is it a durability issue?

 

The all purpose mud [green lid] is for the initial tape coat - it has better adhesion properties. Any of the other types of mud are fine for the other coats.

 

For the patching, I would use durabond. It comes in a powder, you mix your own in the amount you need. It dries quickly and by chemical reaction, not evaporation. It is stronger than joint compound and will allow you to partially fill the void in your light can holes before you apply tape. Wet the tape to help it stick to the compound before it sets up. Regular and Lightweight joint compound are for doing seams only, not for repairs as you have stated.

I have not purchased a large bucket of joint compound in years, but always carry durabond 20 min on the truck. The more you use it, the easier it is to work with. Here is a link, it is for 45 min. mud as the 20 min. will set up in the pan before you have a chance to get it on the wall. Mix in small batches, only what you can use in a short time. SHEETROCK Brand Easy Sand 45 18 lb. Setting-Type Joint Compound-384210 at The Home Depot

 

I am using Ready Patch in the repair areas.

All the versions say they are all purpose. I suppose I'll go out and grab the green lid. Is there any reason not to use that for the whole job? I'd rather stick with one version if I can. I don't want to wind up with several partially used buckets at the end.

 

They say the lightweight j/c sand a little easier but there is no reason that you can't use the all purpose for the entire job. I also like to use durabond for repairs because it speeds up the time it takes although whenever feasible I like to use regular j/c for the final coat. Personally, I'd rather apply an extra coat of mud than have to do much sanding. I've never used the 'ready patch' so I can't comment on how well it's suited for the job or applies.

 

Ready Patch is a repair spackle. Supposed to dry harder with little to no shrinkage. I know years ago a painter liked to use it when he had to lay it on thick. I also read another advice page that recommended spackle to fill large gaps.

I'm hoping not to do much sanding either. But we'll see how well I do with the mud. I picked up the green bucket. I have no idea how much I need. If I use the whole bucket and need more, I'll get the light weight to finish up. The green stuff is HEAVY.

What kind of consistency should I be looking for? Should I mix it down with some water?

 

I've heard of ready patch but have never used any.

I like to thin the j/c a little, it makes if flow better. I never have paid a lot of attention to how much water I use - I just add water and mix until it looks right...... I know that doesn't help you much Try adding a little bit to start, maybe a half a cup or so for the entire bucket or if you are just mixing up a pan full - a couple of spoon fulls. You don't want the mud real thin, just loose enough where it will spread nicely.

Maybe one of the others can do a better job than me at explaining how much to thin the mud

 

The only time I thin down JC is when I am spraying a texture. Ready mix has a nice consistency to begin with. I work it in the pan a little to get rid of any air bubbles. I will also work it on the wall for the same reason, air bubbles, before I pull my bead to feather it out. Too thin, and it will fall off the knife as you are trying to spread it on the wall. Thinned down, it also takes longer to dry.

 

Ok. So I don't think I am doing a very good job putting the mud on. I really want to avoid as much sanding as possible. I'm trying to do my corners without a corner tool. Maybe this was a mistake. I know I can only mud one side of each corner at a time. Getting the second side on nicely seems to be a challenge for me. My 90 degree corners aren't so bad. It's the less than 90 I am having the most trouble with. Any tips would be appreciated.

 

For final sanding, don't use sandpaper. I use a wet (not soaked) sponge wrapped in a silky synthetic fabric rag, not cotton because of the lint. I think there are sponges made for drywall, I never used one. This not only removes high spots but fills in the low spots. No dust. Just rinse it in a bucket when it gets too dry and loaded with mud.

 

They do make a sponge with a handle for smoothing out j/c. I like it especially when working in an occupied dwelling - no dust For a sponge to work well the mud needs to be applied fairly evenly. A wet sponge will soften up the j/c and move it around but there are limits to what it can fix. While very dusty, a sanding pole will level out uneven j/c better than any other method.

Believe it or not, I've never used a corner knife. Before I acquired a little experience I had to mud one side of the corner, let it dry and then go back and do the other side.

You say you are having the most trouble with the corners that aren't 90's - would this be an attic with off angles where the wall goes up so far and then a cathedral like ceiling? If the framing or the hanging isn't right they can be a bear to fix. One way to cheat is to use a rubber paddle like drywall knife. It will make the angle rounded instead of a crisp line. The only downside is it makes it difficult to paint the wall a color and the ceiling white. I usually recommend painting the wall and ceiling the same when the room is done that way.

 

This is the reason I use Durabond, quick setting compound, I can't afford to wait a whole day between coats. Here is how I would attack the situation: For those angles that are not 90 degrees, I have a bit of an unconventional way to progress. Keep in mind that I use a quick set mud, I pull on one side and let set up. I pull the other side and let set up. I then take my 6 inch stiff knife and scrape down any high spots following the direction of the tape. This will give a sort of "needs some work" transition corner. I then apply my next coat heavy on the seam and pull a 12" knife perpendicular to the joint removing most of the mud and working my way down the wall. Yes it leaves streak marks from the knife, but you knock those down with a 6" knife when the mud sets up. This fills the void between the two planes. Then you sand to the desired profile. Its a similar procedure I use when you have a major hump in a wall from a bulging stud that causes two sections of rock to be out of plane. But, the above can be accomplished is several hours as opposed to a couple of days waiting for mud to dry.

 

I probably should have added that a sponge doesn't really work when using setting compounds like durabond. A wet sponge works by rewetting the j/c, fine for the ready mix mud but setting compounds aren't water soluble so you are pretty stuck with dry sanding.

I also like to use durabond but I generally use regular mud for the final coat - it sands easier

 

This is for my house so I am willing to deal with the added time of using a ready mix. I'm not experienced enough to get involved with a setting compound. I would have to mix small batches all the time and probably toss a bunch in the garbage. The ready mix is just going to be easier for me.

Well, maybe I'm not so far off with what I'm doing after seeing the comments here. Mark, you are right about this being an attic space. Maybe my expectation of having a near imperfection free surface on my first few coats is not realistic. I guess once I get enough coats on, I'll be able to go back and touch up my trouble spots. I might try that sponge technique, but that may make things worse. I do want a nice crisp line on those off angles. There are a couple spots where the framing is boogered, but I think I have a chance of making it not so bad looking.

 

I just got done working on my corners with my next size up knife. It seems to be going on a little easier and nicer now. The very inside of the corner may not lay out perfectly, but I should be able to clean it up with some sandpaper and not a lot of effort. We'll see when I get there.

 

One modification I do to my drywall knives is to round off the corners of my larger knives. The rounded off corner lessens the change of leaving a ridge or slight drag mark as you are feathering. Makes for a smoother bead. You need not go at it with a grinder, just ease the corner and knock off the sharp machine point.