Can Pressure Cooker Indicator Weights Be Repaired?

Pressure Valve Weights

• Some pressure cookers might not rely on weights to control pressure, but all pressure canners use either weights or gauges. Missing weights lengthen the cooking times of dishes prepared because steam vents at lower pressures. Adding weights to the pressure valve raises the temperature because increased pressure raises the boiling point of the water inside. Extending cooking times to compensate for missing weights might not kill the botulism spores that cause low-acid canned food such as meat or beans to spoil. If possible, buy replacement weights instead of repairing old ones. Faulty repairs can fail during use.

Metal Epoxy

• Water and heat dissolve and soften many strong adhesives, but some epoxy compounds resist high temperatures and moisture. Not all epoxies bond to metal, and some epoxies fail near the upper temperature range of a pressure cooker or canner. Check the label for information on the glue's operating temperature range before making repairs. Pressurized steam venting under a 15-pound pressure weight reaches 249.7 degrees Fahrenheit at sea level, according to Independent Pipe and Supply Corporation. A metal epoxy glue with an upper temperature limit of 300 degrees Fahrenheit gives the repair a safety margin of 50 degrees.

Using Metal Epoxy

• Combining an epoxy resin with a hardening agent converts the liquid resin to a tough, hard plastic. For a strong repair in a broken pressure cooker or canner weight, the broken pieces must fit together tightly without large gaps. Metal-bonding epoxies can fill gaps as wide as 1/4 inch, according to Pacer Technology, but gaps due to missing pieces reduce the accuracy of the weight. Metal epoxy only cures properly if mixed and applied at a temperature between 65 and 80 degrees Fahrenheit. Above or below that range, metal epoxy stays fluid or forms a weaker bond. Buying new weights eliminates the risk of failed repairs.

Repair Tips

• Any oil or moisture in the metal prevents epoxy from bonding, and any dirt or loose bits of metal also weakens the repair. Rub the parts clean with a cotton cloth dampened with denatured alcohol, available in the paint department of most hardware stores. After the pieces thoroughly dry, brush the broken surfaces with a wire brush to break the layer of metal oxide that quickly forms on bare metal. Mix and apply the epoxy glue according to the manufacturer's instructions. Rub the parts clean of excess glue with cotton cloth and denatured alcohol before the epoxy sets. Clamp the pieces together until the glue joint reaches full strength.