Permanent Metal Repair Paste Set Magic metal mending agent developed as an alternative to torch welding, Metal repair paste provides strong and long-lasting repairs to metals and multiple other surfaces. Metal repair gel will bond almost any clean surface that is free of dirt and oil. High Temperature Resistance A+B repair glue can withstand temperatures up to 150°C. When fully cured, it is as hard as iron and provides uniform bond line thickness. Stainless steel cast iron metal repair agent glue.