I would modify a 1 inch metal putty knife to the needed width to make the glaze. Make a template of the existing glaze, the use the bench grinder to shape the knife, angling the sides to use as a guide between the glass and the metal frame. I do not think wood would work very well with glazing materials. If you are using glazing putty, use a small amount of linseed oil as the lubricant to smooth the finish. If using the newer glazing compounds, the type of lubricant would be determined by the composition of the compound. Water cleanup, use water; mineral spirits cleanup, use either linseed oil or mineral spirits.
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| stylized shape of the knife
/ blade after alteration
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