Case: Flame-toning Replacement Bays on Baroque Copper Roofs
名建筑案例：巴洛克铜屋顶补配的火焰做旧
标签：铜屋顶, 巴洛克, 补配, 做旧, 教堂
欧洲巴洛克教堂铜塔顶换新时，新铜皮（数周内即亮橙）与数十年深褐老铜并存的接色是修复难点。某项目做法：新瓦先以低浓度醋酸氨液催出基础灰绿（分 5 日喷涂），阴干 48 h 后用软火焰距 15 cm 快速扫过补配边缘，把催绿层的"生涩灰"烧成熟化的橄榄褐色，与老瓦形成 3 级色阶过渡；接缝线 100 mm 内不做火焰，留待自然气候统一。要点：火焰只做过渡不做整面，过度热处理会烧毁新生碱式铜盐使补瓦再度露橙。
When Baroque spire bays are renewed, fresh bright-orange copper next to decades-old dark brown is the conservator's headache. One project's method: pre-green the new sheets with dilute ammonium acetate (sprayed over 5 days), dry 48 h, then sweep a soft flame at 15 cm quickly across the patch edges only — turning the "raw grey" verdigris into a mellow olive-brown that grades in three steps toward the old bays. The last 100 mm at seams is left for weather to unify. The flame blends but never covers whole bays: over-heating burns the fresh basic copper salts and re-exposes orange.