I will start this off by saying that plaster deterioration is a natural process. It's not uncommon to find a piece of glass with its plastered "part" still holding on tight. However, I certainly wouldn't pass up that lamp, cruet, epergne or newel post finial simply because the plastered attachment is loose. Loose plaster does not affect the value of the piece (unless you use it as a bargaining tool against the unknowledgeable dealer). Damage can certainly result when fail to preserve these articles of the past.

First, ensure that the substance holding the loose "part" is in fact, plaster. I have found early lighting with parts attached with Elmer's glue, super glue, putty, and some other unidentifiable materials. The non-water soluble materials generally appear shiny and are extremely hard. Unless the material is easily recognizable, scratch the material with a nail or other small metallic instrument. This will easily leave a mark in plaster and you'll notice a powdery substance on the end of the instrument. If the material is solid, shiny and extremely hard, don't proceed any further. The material can still be removed, but I would recommend having someone who is familiar with the process attempt it. However, if you have an item with little or no value, you may want to use it as a "practice piece."

Before a loose part can be reattached, it must be removed from the main piece. All traces of plaster must be removed from both pieces. Once both parts are cleaned, free of old plaster and dried, mix the new plaster (add color if necessary) and reattach the part. Gently wipe off any visible excess plaster with a damp paper towel and let the piece sit undisturbed for at least twenty-four hours. If the piece is disturbed prior to this, you may very well end up repeating everything you have done thus far because the plaster has not fully set. If this occurs, don't worry, it happens to the best of us.

PART II:

Temperature:

The first step in replastering is to remove the loose piece by soaking it in one of two common household solutions: water or white vinegar. However, before your glass is placed in any liquid, check the temperature of your glass and the temperature of the liquid. Both should be at room temperature. Ensuring that your glass is room temperature is very simple, allow the piece to sit in the room for ten hours. The temperature of the liquid can be manipulated by adding warm water or by placing your hand in it for a couple of minutes. Most EAPG is utilitarian and was intended to be washed, cleaned or filled at some point, so we aren't doing anything to it that hasn't been done before. (Never sit a piece of glass in a metal sink, a metal sink will always be cooler than the ambient room temperature and your glass.)

Soaking old plaster:

The only liquids I use are water, white vinegar, or a combination. One is no better than the other and both will work. Vinegar may work faster depending on the type plaster to be removed and may discolor metal ware, but don't worry, there is no harm and the metal will clean. By "type" of plaster, I mean there will be variations in ingredients from manufacturer to manufacturer and not all will loosen in the same amount of time.

To loosen old plaster, I have soaked it from 2 hours to 30 days with the average being 4-6 days. This range, in my opinion, is due to the substance that has come into contact with the plaster over the years and permeated the porous, absorbent, plaster such as oils, kerosene or syrups. If at all possible, I prefer to submerge the entire piece in our liquid, however, in the case of a lamp the center brass connector will likely be loose and the collar not. In this case I only submerge the piece, just above the plaster to be loosened.

After a day or two scratch or probe the plaster to get a feel for it's transition back to it's thick liquidous state. If the part to be removed started with some looseness that's an added bonus. Be patient! If there is movement, the part can be separated but don't rush it. It will now be necessary to remove the piece from our liquid and manipulate the looseness by gently moving the part back and fourth, then returning it to it's bath. This will most likely be repeated several times before the parts separate. After handling your piece, be cognizant of the temperature of the glass before returning it to the bath (they should both be room temperature). The process can be shortened by probing or picking away pieces of plaster that are accessible and moving the piece under ROOM TEMPERATURE water. Tools I use for this are very tiny screwdrivers, toothpicks, nails or dental picks, all of which are available. Again, Be PATIENT and NEVER lodge a probe between plaster and glass and NEVER turn or twist the probe, pick, pick, pick!

NOTE: If water feels neither warm nor cool to the touch, but simply wet, it is most likely safe for your glass. You must be the judge.

The plaster may be over 100 years old, don't plan to remove it in 20 minutes!

PART III:

Cleaning the surface:

Once the loose piece or part is removed it will necessary to remove all traces of plaster from both the attachment and the host piece. It may be required that larger pieces of plaster, still adhered to metal parts, be picked away by using our dental pick, small screwdriver or other probe. Once the larger pieces of plaster have been freed, both the glass and it's part will still retain residue or bits of plaster. These can be removed by means of brushing with a steel brush or a brass brush for sensitive metal parts (I use a steel brush on my glass lamps, brass collars and connectors). Be careful not to brush the exterior of metal because it may scratch. In my experience, a steel brush will not scratch glass. Brush the area that retains plaster residue while holding the pieces under ROOM TEMPERATURE water. Once this step is completed, dry all pieces with a paper towel and let them sit to dry further.

Mixing the plaster and coloring:

In order to preserve our glass, it is critical that the only substance used to reattach a separated, plastered part, is a water-soluble plaster. I have discovered an outstanding product that is the only material I will ever use, "Durham's Rock Hard Water Putty." This plaster is available at many home improvement stores, such as Lowe's, Home Depot, etc. It is pre-tinted a light tan, and extremely inexpensive, less than $2.00 for can that provides enough plaster for several jobs.

Place two-three heaping tablespoons of the powder into a small glass dish. Mix a small amount of water into the powder to create a mixture the consistency of toothpaste. If you have never attempted this, it may be necessary to add more water or more plaster to achieve this consistency. Plaster that is too dry will not set properly and plaster that is too wet will be difficult to work with.

Although this plaster is pre-tinted a light tan it will still look new when dried. Some of the many tricks for color aging plaster are mixing in a powdered tint, water soluble wood stain, fireplace ashes, or wiping dried plaster with used motor oil. All of this is tricky because we must still maintain our toothpaste consistency and be careful not to affect the integrity of the plaster by mixing in something that may affect it's ability to properly set. I am personally a fan of water soluble wood stain.

Reattaching the part:

With our tablespoon drop a small amount of plaster into or on the loose piece to be reattached. With a finger coat this small amount of plaster around the interior of the part. Once coated, add a sufficient amount of plaster, so that when reattached, a small excess will squeeze out. Reattach the part, position it, and hold it firmly to the base piece. Wipe the excess from the exterior with a damp paper towel and let go (don't worry about cleaning off all the excess plaster, we will do this later). Again, after completed, fight the urge to touch it for 24 hours. If the mixing and reattachment steps have to be repeated, don't worry, our materials are inexpensive and we have time on our side, just clean our glass and loose part thoroughly, dry them, mix our plaster, and off we go. When the plaster has thoroughly dried, take another damp paper towel and wipe the excess plaster as your piece demands. Other "dried" plaster excesses can be CAREFULLY scratched off with our probe.