One of the least understood processes associated with the making of a leaded glass window is the cementing or grouting of the panel. This article has been written with the hopes of shedding some light on the subject.

The reasons for cementing a window are to weatherproof and strengthen the panel. Even if a window will never be exposed to the weather, it is still necessary to provide the window with the extra support it needs through the cementing process. Consider the fact that glass is heavy (about 1 ½ lb. per square foot for 1/8" glass) and lead is pliable. If you combine these two with the force of gravity, the window will sag and ultimately crack.

In addition to the structural considerations behind cementing a window, the favorable aesthetic effect proper cementing has on a panel should not be overlooked. The brushing action in combination with the carbon black in the mixture darkens both the lead came and the solder joints which tends to soften the harsh lead line giving the panel an overall finished look.

Even though cementing a leaded window may not be everyone’s idea of a good time, it is however an essential step in the window making process and unfortunately there is no easy alternative except maybe to have someone else do it.

Because this is an inherently messy procedure, you don’t want to do your cementing on the coffee table. The area you normally use for your window assembly may be able to be used for this purpose providing you protect your work table and other items from the dust and debris generated while cementing.

If your work table space is limited, you may want to cement on a separate piece of wood such as masonite, particle board, plywood, etc. that is removed after the cementing process is finished. Another suggestion is to do your cementing out of doors when the weather permits.

No matter where you decide to cement a panel, it is essential that you wear a snug fitting filter mask of good quality. The dust that is present in the air while cementing can cause a variety of potentially serious respiratory ailments (refer to page 6). The dust can be aggravating to allergies and asthma. They may even contain lead oxides which are scrubbed from the cames by the brushing action.

For additional safety information on Inland Cement, refer to the MSDS sheet.

1. Open the tub of Inland Cement and mix thoroughly using a putty knife or paint stick. Make sure that you scrape the bottom often. When ready to use, it should be smooth, have no lumps, and have the consistency of cake batter.
2. Pour small pools of cement on to five or six areas of the window.