Finishing fast - setting vs. drying
 

It's come up again - I have a drywall patch to do, and I need to get it done in about 18 hours. Normally I use premixed drying compound, and just wait 3 days for 3 coats to dry.

If I need to do something faster, I'll use a setting compound for the first coat or two. I don't do big production work, but I do take pride in how smooth the finished product is, and that means some sanding. I try to sand less, and finish smooth more, but still, I'll be doing some sanding.

So how can you get this done in a day? Even though setting compound sets up firm, you still can't sand it because it's still damp. Is there some secret I'm missing? For a tiny job you could dry it with a hair dryer or something, but for a whole wall, even fans take awhile.

If it's not a big patch use 5 minute mud for the first 2 coats smooth them well as you apply, just knock down any high spots or ridges don't need to sand. When dry top coat with that new ultra lite mud (puke green lid) can go on thin and dries fast and very easy to sand. If the patch is larger use 20 minute mud, if you mix it with warm water it will set faster. If you use the setting mud all 3 coats you will find it's harder to sand.

Well, when I say "patch" I usually mean something bigger, like a wall or half wall (including corners) that had to be re-drywalled due to water damage or something like that. Do you find you can put the first 2 coats on along all the seams without having any sanding? That would be a feat for me.

If your not that good you mite be better of getting 20 or 45 min.For less sanding,as it dries take your knife and knock down the ridges.If you find you want it to dry faster use hot water.

Sorry just noticed i said the same think as toolseeker

For a patch that size I would just use the hot mud-setting-for the 1st coat and to do any fill use it to set your tape wipe it thin and it doesn't need to be pretty the main thing is to leave no humps, ridges don't hurt. when dry take your knife and scrap any ridges off. Any low places will fill with the next coat. Second coat use the pre mixed in the bucket with the bright green lid that is all purpose and feather it out a little farther than the 1st coat and remember you don't need to leave a lot of mud. sometimes on 2nd you can still see the tape. You can use the all purpose for your final coat but it is a little hard to sand. For I think $12 you can get the ultra lite (puke green lid or # 3 blue lid) for your final coat. If you are going to do corners I would use paper tape the mesh is almost impossible to do corners with. 18 hours is going to be the hardest part so concentrate on the first and second and you may not need a 3rd.

This worked well for me today. While "set", it was still easy to scrape off any high points with my knife.

I don't have any trouble on the basic seems and corners. It's in the tight areas where I have to make "swirls" and unusual moves around switches, fixtures and trim that I have more trouble getting it smooth without sanding.

Try using a sea sponge while it is damp but not set, blending the edges to smooth taper (no sanding). I first coat, paper tape, coat over the tape, both with the same mix of 20 min. This coat should be thicker than drying type coats as you are doing one less step. Feather the edges with the blade, again, before it sets. Mix more 20, but thinner, feather edges and fill any remaining lows, follow immediately with a squeegee or knock-down blade (bigger to level better), no third coat, not required or needed if applied thick/smooth enough. Bend your blade to create an arc or use a trowel with a camber from the factory and a hawk. Wipe with the wet sponge as it is setting, just after cleaning mud pan/tools. Takes some getting used to, though it is very quick.

Gary

I'm glad you reminded me because that's the other technique I've been meaning to try - sponging.