10 Things Not to Do Restoring Old Plaster Casts

Antique plaster casts preserve an important story. Like art objects are as beautiful as vulnerable. If an old cast came up to us retaining the marks and wounds of the time we have to appreciate it also for that. The restoration is not always necessary. Every action that takes place in the ‘wrong’ attempt to bring them back to their original appearance could only compromise them. The most important thing is to consider the real need for a restoration.
Many collectors prefer to keep the old cast in original condition with the patina of time, the damages, and the signs of improper conservation. I completely agree.
When the cast appear seriously compromise is good to proceed with a restoration but having absolutely respect for everything is original.
1— Do Not cleaning the surface with any abrasive tool or sand paper. Surface of a plaster cast is really delicate and also one of most important things that give fedelity and value.
For first clean with a soft brush. Then, if the surface is strong, clean with a soft air.
2— Do Not remove any patina on the surface, also if it is bad and probably not original.


Proceed with small tests in hidden parts only with solvent and chemicals (with high evaporation) on cotton wad.
3— Do Not attach fragments and separate parts with any adhesive, resin or other glue.
The best way is to restore fragments with plaster but to do this need to soak the dry surface. If this is not possible, just wet and use vinilic glue (Vinavil® 59).
4— Do Not attach separate parts (arms, legs, head) that were done separately.
Use the same original mounting system with joint tools.
5— Do Not use cement o resin to fix a damaged base. Keep the old plaster cast as it is and make a custom wood base to stand it.
6— Do Not remove old rusted steel armor inside. Use on it a metal rust converter before fill the hole of lost fragments with plaster.
7— Do Not consider low value an old plaster cast with lost or destroyed parts (nose, ear, finger, arms). Consider its historic value and ask for a professional restore using parts from a modern cast to complete it.
8— Do Not remove plaster seam, brass label, engarved sign, paper label on the surface.
9— Do Not apply any color layer (enamel, white color, tint).
10— Do Not begin a restoring work before looking with attention the plaster cast trying to understand the technics of fabrication, materials used, its provenance, manifacture, date of fabrication and recent history. Any information will be useful before restoring.
If you decide for a professional restoring remember that: an antique plaster cast is one of most difficult work of art to restore. Most of restorers don’t have a great knowledge on this material. So, ask only to experienced professionals of whom you personally know other similar works done before. The best thing to do is ask to a good professional mold maker to do the work of restoring.
By my experience and after seeing a lot of ‘bad restoration’ and ‘miserable repairs’ of antique casts, my advice is this: ‘Less you do; more you have done’.

Plaster Cast of the Bust of Lucius Verus
(original marble at the Louvre) of the late eighteenth century.
Damaged in some parts and with broken nose.

Restoring lost parts using fragments in plaster casted from the original.

The old plaster cast restored with the purpose of a better appearance
but respecting and preserving the original patina and broken unimportant.