Restoring/Reproducing Ornamental Plaster and Medallions

One of the reasons that I bought my 1905 Neo-French Renaissance house was that it had ornamental plaster ceiling decorations and medallions. The decorative plaster ceilings had been either badly damaged, heartlessly nailed into, covered, or plastered over. The house was also missing medallions in certain of the rooms. I was told the ceilings could not be saved. This is the story of how we found the blue goo mould making material (left photo) and resin based casting material (right photo) and restored the ceilings and medallions.

I received this beautiful book for Christmas written in 1897 by William Millar entitled “Plastering Plain and Decorative” (I have the 1927 edition) and delved into the gorgeous plates and detailed instructions on everything you ever wanted to know about decorative plaster.

The 1897 book suggested several methods. I tried making a wax model and then pouring in plaster of paris. That didn’t work; I ended up with a fused mass of wax and plaster. I then tried making a clay model and pouring over a polyurethane mould making material and ended up with clay covered in polyurethane. The book also suggested that decorative plastering was done like decorating a cake, so I filled a pastry bag with plaster, and ended up with a pastry bag shaped piece of plaster because modern plaster dries too fast. The book also had recipes for plaster, but where was I going to find ingredients like ox hair in modern day Brooklyn?

When my contractor stripped off the 1970s plaster job in the Library, underneath was a faint painting of the original decorations that had been obliterated. So, the 1905 master plasterer must have painted the decorations first, but then how were they applied? We also uncovered a medallion under an incredibly ugly 1970s light fixture and I looked at hundreds of medallions to no avail; I couldn’t find reproductions to match the medallions that the house had.

My Mother and I experimented with a mould making material from a company called Abatron, which worked. It is called Master Mould 12-3. I made a 40 pound cast that was too heavy to install and the guys laughed.

I hope you are laughing, too.

Then, we used a light weight resin casting material from Abatron called WoodEpox, which made a perfect replica.

Dave Cummings restored all of the ornamental plaster decorations and medallions so seamlessly that you cannot tell which is original and which is a reproduction.

So, if a contractor tells you that plaster decorations cannot be saved, try the mould making and cast making material first. Apparently, you can also make a mould of a three dimensional object like a lion’s head, although I haven’t tried it.

The mould making and casting material is available from www.abatron.com
5501 95th Ave.
Kenosha, WI
262-653-2000

Dave Cummings can be reached at 718-864-2906 or DaveE718@hotmail.com