This is my first experience with drywall, so as I have pointed out in my other threads, I have no real idea what I'm doing!
I thought I wanted to use a setting compound for my corner tapes, to make some deep fills for repairing a few damaged spots in the drywall, and to fill in a recessed area that I wanted to bring flush up to some trim after removing hardboard from the walls, as shown here:
I picked out USG Silver Set 90 instead of Durabond 90 since I figured that would be easer to sand down when I made a mistake and needed to remove some. It seemed to work well when doing the deep repairs, and starting some inside corner taping, but then I made a batch for doing the second coating over the tape that I couldn't seem to get to go on right (getting crumbly right in the corner instead of smoothing nicely).
So, I went back to re-read the instruction for mixing on the bag, which seem simple enough and didn't suggest any problem except that I didn't mix quite as long as they suggest, but then I read farther down and found "Application to porous surfaces or at less than 1/8" thickness may prevent chemical setting and bond." What the heck? Lowe's website recommends this stuff for taping, but that's going to be using it at WAY less than 1/8" thick.
I looked up a USG "submittal sheet" for this stuff
https://www.usg.com/content/dam/USG...ttingtype-joint-compounds-submittal-J1649.pdf
which doesn't say anything like that language on the bag. It says to tape with a thin edge, as you'd expect.
Can anyone make sense of this?
Nothing I've done seems to be falling apart, so I hope it set properly, but I may quit making this more complicated than it needs to be and pick up a bucket of green lid premix!
I thought I wanted to use a setting compound for my corner tapes, to make some deep fills for repairing a few damaged spots in the drywall, and to fill in a recessed area that I wanted to bring flush up to some trim after removing hardboard from the walls, as shown here:
I picked out USG Silver Set 90 instead of Durabond 90 since I figured that would be easer to sand down when I made a mistake and needed to remove some. It seemed to work well when doing the deep repairs, and starting some inside corner taping, but then I made a batch for doing the second coating over the tape that I couldn't seem to get to go on right (getting crumbly right in the corner instead of smoothing nicely).
So, I went back to re-read the instruction for mixing on the bag, which seem simple enough and didn't suggest any problem except that I didn't mix quite as long as they suggest, but then I read farther down and found "Application to porous surfaces or at less than 1/8" thickness may prevent chemical setting and bond." What the heck? Lowe's website recommends this stuff for taping, but that's going to be using it at WAY less than 1/8" thick.
I looked up a USG "submittal sheet" for this stuff
https://www.usg.com/content/dam/USG...ttingtype-joint-compounds-submittal-J1649.pdf
which doesn't say anything like that language on the bag. It says to tape with a thin edge, as you'd expect.
Can anyone make sense of this?
Nothing I've done seems to be falling apart, so I hope it set properly, but I may quit making this more complicated than it needs to be and pick up a bucket of green lid premix!