Plastering a fireplace arch

[cwhaley]

We have opened up a fireplace to install a woodburning stove (hasn't everyone...), which exposed the original supporting brick arch above the builders opening. We don't want the exposed brick but we do want to retain the curvature of the arch. I want to plaster over it but I'm struggling to think how I'll get a decent curve through rendering and plastering. I'm fine with the walls on the chimney breast front, but I'm struggling with ideas on the arch.

The arch itself isn't perfect so I wouldn't want to follow the edge of it as it currently sits. I also don't want to use the metal/plastic beading as the expansion/contraction will crack the plaster.

- Would I be able to form a plywood arch (supported at either end) and render/plaster up to this?
- If so, when can I take the plywood away without damaging the finish?

Thank you!

 

[chappers]

yep no problem. take it down next day

 

[cwhaley]

yep no problem. take it down next day

Thank you. Closest thing I've come to this is by using the plastering stop beads which obviously stay in place, so was a bit nervous about when I could take the plywood away without damaging the work.

Thanks again