On 07/09/2016 2:25 PM, Percival P. Cassidy wrote:
I repaired some holes in a wall that is to be wallpapered, and then
started applying "Shieldz" to provide the proper surface for the
wallpaper -- and now, an hour or so later, I find that the drywall
compound is lifting up and falling off at the nicely tapered edges. The
dry-wall compound has had a couple of days to dry.

What have I done wrong?

Dunno'; never used the product. The Tech Data sheet doesn't say
anything terribly much on new drywall; does say plaster must cure 90
days before using the product. I'd guess the two days wasn't long
enough, but I'd contact Zinnser and ask what happened/how to fix/prevent.

http://www.rustoleum.com/~/media/DigitalEncyclopedia/Documents/RustoleumUSA/TDS/English/CBG/Zinsser/SHZ-02_ShieldZ_Universal_Wallcovering_Primer_TDS.ashx

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