WMWCS

There are two methods we use - for outside windows we use a squeegee and washer. Inside we use microfibre cloths. Both systems when properly applied have the advantage of not leaving smears. Using microfibre clothes inside avoids the risk of drips falling onto carpets or other interior fabrics.

The squeegee is a carefully angled strip of rubber that removes the surface film of water and dirt. Only a small amount of detergent is needed in the process. The detergent is not there to clean the glass, the physical action of the washer and squeegee do that, the detergent is there to act as a lubricant to the rubber blade as it glides over the glass removing the film of water and dirt. Normal cloths get wetter and wetter as you use them to clean the glass and this results in different amounts of water being left over the surface of the glass. Under a high powered microscope glass is not smooth but has quite a jagged surface with many reflective surfaces. The different thickness film on the glass reflects light differently and results in smears. When a squeegee is used properly this does not happen.