The world of house restoration is full of old, well-known, traditional materials. Wood, nails, and paint have been around for centuries; their uses and characteristics are known; and in most cases they are the appropriate elements to use in restoring or repairing a part of your home.

However, there are times when something new is needed to solve a specific problem. A new material may have characteristics not found in traditional materials. Something new may be stronger, lighter, easier to apply, or less hazardous than a traditional material. If used in an inconspicuous place, the newer material will not detract from the visual character of the house.

The topic for this case study is the newel post light fixture in the front hall of our 1877 Stick-Style Victorian. This fixture is now electric, but was once a gas fixture. Like many ornamental lighting pieces from the 1870's, it is made from pot metal and painted with a decorative finish to imitate bronze. Pot metal is an alloy that is inexpensive and easily cast into complex shapes. For a contemporary example of it, dig into your child/grandchild/whatever's toy box for a Hot Wheels car: the body is probably cast from pot metal.

One disadvantage of pot metal is that it isn't very strong. Our light fixture is held to the top of the newel post by three wood screws. Over the years, the stress on the metal around the screw holes has resulted in cracks radiating away from the holes. When I found these cracks, I became concerned that the next time someone came down the stairs and held onto the fixture while rounding the corner, the stress would cause the screws to pull through the fixture, bending the metal and making a repair difficult. My job, then, was to find a way to strengthen the metal around the screw holes so that the cracks wouldn't get any bigger.

My first attempt at repair was to solder small sheets of copper to the inside of the fixture. I used copper roof flashing cut into shapes to fit into the inside of the fixture around the screw holes. I used a wire brush attachment on a Dremel moto-tool to clean the area around the screw holes on the inside of the fixture. I then brought out a soldering gun and standard rosin-flux tin-lead solder and spent some time discovering that pot metal isn't solderable. The molten solder simply didn't wet the metal, even when it had reached the proper temperature.

That was when I put my thinking cap on and looked for an alternative. After considering the problem for a bit, I decided that if I couldn't attach strengthening sheets of metal with solder, I could attach fiberglass or carbon fiber with epoxy. This is known as a composite - something made up of layers of a strengthening material held together with an epoxy binder. After shopping around a bit, I decided on carbon fiber mat as the strengthening material. This material is a thin fabric, similar to a felt, that is composed of randomly-oriented carbon fibers.

Shopping for Composites One place to find small amounts of composites are companies that sell to model airplane hobbyists. These companies usually offer woven fiberglass cloth in various thicknesses, carbon fiber in a wide variety of forms, and various formulations of epoxy. I purchased my materials from Aerospace Composite Products , although there are other retailers that can be found from a quick web search.

The general process of forming or applying composites is straightforward. First, a layer of the fabric material is applied to the inside of a mold or the outside of a form. Then epoxy is applied until the fabric is completely wetted, the fabric is smoothed against the surface, and excess epoxy is removed. The epoxy is allowed to cure, then additional layers of fabric and epoxy are applied, if necessary.

Before I started this process I again cleaned the inside surface of the light fixture with a wire brush. For proper epoxy adhesion, the cleanliness of the surface is critical. As a final step I used acetone (isopropyl alcohol would be a good substitute) to remove any traces of fingerprint oils. I applied masking tape to the outside of the fixture over the mounting holes, so that epoxy wouldn't seep through and mar the outside surface.

I then cut pieces of the carbon fiber mat to fit the inside of the base of the fixture and started mixing epoxy. I held the mat in place and brushed on the epoxy. I wore disposable latex gloves, and used my fingers to smooth the mat against the inside surface of the fixture. The epoxy was sticky and thick enough to keep the mat against the surface of the fixture without requiring something to hold it in place.

I applied three layers in total, allowing each layer to cure overnight before applying the next. After the final cure, the composite had a thickness of about 3/32 inch (2 mm). The base of the fixture now seemed very solid. I trimmed away some material that extended over the bottom edge of the fixture, and carefully drilled holes through the composite that covered the screw holes. I then reinstalled the fixture, being very careful to tighten the screws to a torque just sufficient to hold the fixture in place securely.

The focus of restoration should always be to prefer traditional materials when possible. But, if no other solution is available, it is good to consider a new approach. By being creative, you may arrive at the best overall solution. My goal was to stop the growth of the cracks and strengthen the fixture for the foreseeable future. I think I've met that goal. The ultimate test of my repair is another decade away, when my sons become teenagers and pivot around the newel post at high speed. I'm crossing my fingers.