"Richard Savage" wrote in message
...


Brett Jackson wrote:
I have coving in my living room of a particular style that I cannot find
anywhere. I want to add a new section of wall and re-create the coving
around that section. I have considered removing all the coving and
replacing it with something off the shelf but I think this would be too
much
work as it's a large room.

This leaves me with 2 options as I understand it:

a) create a wooden profile of the coving and attempt to re-create
in-situ
using plaster that's sculpted using the wooden profile.

b) create a mould and use this to cast the new coving using some form of
light-weight plaster.


My question is, both of these seem like they would be very tricky, and
I'm
sceptical that the result wouldn't look too good.

Does anybody have any experience of doing such a thing in the past? I
would
be grateful of some advice, particularly with regards to the materials
that
I should use?


Many thanks
Brett



I've seen it done with, as you suggest, a profile. But AFAICR it's done
in sections on a bench against a corner shaped former with scrim(?)
bedded in the plaster to give it strength. I can't remember how the
sections are held in place.

Richard
--


Reply to RJSavage at Bigfoot dot com


Some ornate but regular linear cross section coving was done in situ by
fixing a batten below the finished level, and running a 'horse' along the
batten . The horse had a longish horzontal bearer on the batten with an
upright that had the rough (but larger) shape of the coving profiled into
it, but a sheet of thin zinc was fixed to it with the exact shape required.
Plaster would be applied to the ceiling/wall join and the horse run down to
shape it - an iterative process - going over it many times to build up the
finished surface, but always in the same direction.

Did this once many years ago when I annexed one side of a bedroom to make
built in wardrobes and wanted to replicate what I'd covered up. Worked ok
but was a messy process - plaster consistancy was difficult to get right.
Too wet and it slumps everywhere - too dry and it cracks like crazy when it
sets. May be better to use plaster of paris ?

Andrew Mawson