Please check your use and care to ensure the knives are dishwasher safe.
Dishwashers provide a welcome relief from the task of washing up but to keep your knives in good condition, a few simple precautions are necessary. Special hardened stainless steels are generally used for knives to give them a lasting edge but these steels can become slightly pitted if left in contact with moisture for too long.
Whenever possible wash knives immediately; do not leave them to dry overnight and do not subject knives to the 'rinse and hold' cycle in your dishwasher.
As soon as the dishwasher has completed its cycle, remove the knives and wipe them dry.
Observe the dishwasher manufacturer's instructions concerning the type and quality of detergent used and the method of loading knives in the compartments provided.
Water with high salt content is particularly corrosive to stainless steel. Dishwashers are often fitted with water softeners that must be regenerated with salt. After adding salt, make certain that the machine is put through the programme recommended by the supplier before washing knives in the machine.
Knives with handles of wood or phenolic (heat resistance plastic), should be washed by hand unless it is stated to be suitable for dishwashers.
If any stains are produced by hard water or by any other cause, they can usually be removed by rubbing them with a non-abrasive metal cleaning paste or liquid.