I note in another post you mention using cornice adhesive or masonry adhesive to attach gyprock to masonry walls.

Can I use masonry adhesive to attach cornices? I have a part bag left over and are reluctant to throw it out

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Jack

The answer strictly speaking is yes it will hold the cornice up and in place as well as cornice adhesive.

The difference is the workability of masonary adhesive compared to cornice adhesive.
You may find that masonary adhesive will set gritty and make it very hard to finish mitres etc.

It would be too frustrating for me to use masonary adhesive to put up cornice. Cornice adhesive is designed to set quicker once used or "worked" yet it can be worked back into a soft state allowing smooth finish on mitres.

My advice would be to toss it and get cornice adhesive. Bags of plaster are relatively cheap. Depending on how much you have to do you could add a couple of handfulls in a cornice adhesive mix without losing too much of the cornice adhesive characteristics. If it meant the diffence of buying one or 2 bags of cornice adhesive.

Cheers Rod

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