A putty knife is a specialized tool used when glazing single glazed windows, to work

putty PuTTY () is a free and open-source terminal emulator, serial console and network file transfer application. It supports several network protocols, including SCP, SSH, Telnet, rlogin, and raw socket connection. It can also connect to a se ...

around the edges of each pane of

glass Glass is an amorphous (non-crystalline solid, non-crystalline) solid. Because it is often transparency and translucency, transparent and chemically inert, glass has found widespread practical, technological, and decorative use in window pane ...

. Putty is often applied by hand, then smoothed with the knife. Modern

insulated glazing Insulating glass (IG) consists of two or more glass window panes separated by a space to reduce heat transfer across a part of the building envelope. A window with insulating glass is commonly known as double glazing or a double-paned window, ...

may use other ways of securing the glass to the window frame. A spackle knife (called a scraper in

British English British English is the set of Variety (linguistics), varieties of the English language native to the United Kingdom, especially Great Britain. More narrowly, it can refer specifically to the English language in England, or, more broadly, to ...

, also known as a

spatula A spatula is a broad, flat, flexible blade used to mix, spread and lift material including foods, drugs, plaster and paints. In medical applications, "spatula" may also be used synonymously with tongue depressor. The word ''spatula'' derives ...

American English American English, sometimes called United States English or U.S. English, is the set of variety (linguistics), varieties of the English language native to the United States. English is the Languages of the United States, most widely spoken lang ...

) is also commonly called a "putty knife", and is used for scraping surfaces or spreading material such as

plaster Plaster is a building material used for the protective or decorative coating of walls and ceilings and for moulding and casting decorative elements. In English, "plaster" usually means a material used for the interiors of buildings, while "re ...

in various

construction Construction are processes involved in delivering buildings, infrastructure, industrial facilities, and associated activities through to the end of their life. It typically starts with planning, financing, and design that continues until the a ...

trades. Widths from 1" to 5" or 6" are commonly available. Wider-bladed knives up to about 12" are used for sheet rocking. Larger blades are made, but generally lack the stability of the smaller blades and do not make a perfectly flat surface. Stiff-blade knives, typically 1 mm or .040" thick, are suitable for scraping. Flexible-blade knives, typically 0.5 mm or .020" thick, are suitable for spreading. Due to the conductive nature of metallic blades, they should be kept at a safe distance from electrical components. Disposable knives, with handle and blade molded as a single piece of plastic, are suitable for occasional jobs such as spreading roof patching tar or mixing two-part adhesives, avoiding laborious cleanup which may involve hazardous solvents.

References

See also