How Do I Clean Up an Old Glass Electric Insulator?

Glass insulators originally were used to protect wires on telegraph lines in the 1800s.

Glass insulators were used during the 19th and early 20th centuries to insulate wires on communications equipment. The collecting of these items has become a popular hobby over the past couple decades. Garage sales are a prime source for finding glass insulators, which are prized for their embossing details and colors. The first glass insulators were used in the 1840s on a telegraph line between Washington, D.C. and Baltimore. Keeping your glass insulators pristine requires care and the right cleaning solutions. Train soot and rust are common forms or dirt that collectors seek to remove.

Difficulty:

Moderately Easy

Instructions

Things You'll Need

• Soap
• Plastic bucket
• Kitchen scrub pad
• Nail polish remover
• Toothbrush or pipe cleaner
• Oxalic acid
• Lye
• Rubber gloves
• Clean rag

1. Clean the insulators with a simple solution of warm water and mild dish soap. This should be your first step in trying to remove dirt and grime. Use a bucket or other container to mix the soap and water and soak the insulators for a few minutes. Getting inside the insulator may prove tricky. If your fingers are too big, use a toothbrush or pipe cleaner. If the grime proves stubborn, soak longer, even overnight. Rinse and wipe with a clean rag, then allow to dry.

2. Use a xylene or acetone cleaner such as nail polish remover if the soap and water doesn't remove all the grime. This method also is good for removing gum residue from stickers.

3. Mix a solution of oxalic acid (often called "wood bleach") and water if soot and dirt doesn't come off with other methods. Oxalic acid commonly is used in rust removal. It's an acid, so wear rubber gloves. Use a plastic bucket (the acid will discolor and damage metal). Use 1 lb. of oxalic acid per 2 1/2 gallons of water. Mix the acid with hot water, let it cool to room temperature and place your insulators in the solution. Cover the bucket and let the insulators soak overnight. The next day, scrub with a kitchen scrub pad or fine steel wool. Use a toothbrush or pipe cleaner to clean inside the insulator. Rinse and wipe, then allow to air dry.

4. Use a lye solution as an alternative to oxalic acid. Mix 12 oz. of lye with 2 gallons cold water in a plastic bucket. Do not use hot water, which will cause the lye to emit nasty vapors. Wear rubber gloves. Lye is very corrosive. Avoid inhaling any vapors. Place your insulators in the solution, allow them to soak overnight and scrub and rinse the following day. Allow to air dry.

Tips & Warnings

• The insulators can be scrubbed, rinsed and re-soaked as often as needed. Troublesome soot may require several days of soaking.

• "Tumbling" is a last-resort solution to cleaning insulators. Water, cleaning compound and tiny bits of copper are used to "tumble" the insulator to remove dirt.

• Insulators made of porcelain, wood and rubber also exist. Porcelain insulators are collected and need to be cleaned in the same manner as glass, but they are rarer and more fragile.

• Beware of artificially induced colors when buying glass insulators. Thermally and radiation-altered colors are on the rise. Beautiful and non-original colors are produced and entice buyers to purchase insulators they may otherwise not consider.

References

• Insulators: Cleaning Your Insulators
• Insulators: Tumbling Insulators
• National Insulator Association: Artificially Induced Colors

Resources

• Auction Bytes: Collector's Corner--Glass Insulators
• My Insulators: Cleaning Glass Insulators